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8tq8r2 | How do MDISC's manufacturer know it can last 1,000 years without actually testing for 1,000 years? | Technology | explainlikeimfive | {
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"Essentially they estimate how much radiation an MDISC would be exposed to in a year and then rapidly expose it to greater amounts to determine how long it takes for the data to deteriorate to the point of unusability."
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8tqrey | What is airport security looking for in liquids, and why are some liquids treated differently than others? | Technology | explainlikeimfive | {
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"Ok so let's talk about something called liquid binary explosives (From here on referred to as \"LBE\") and why the liquids restriction barely has anything to do with preventing someone blowing a plane up using liquid explosives. What is a Liquid Binary Explosive? It is basically an explosive compound that is formed from two or more other compounds that may or may not in of themselves be explosive, but as soon as they are mixed, the resultant mix IS explosive to varying degrees. Let's take a myth about liquid binary explosives and throw it out before it muddies the issue. The majority of LBE's are \"liquids\" in as much as oatmeal is a liquid. They are for the most part extremely viscous with one or two small exceptions which I will come back to. They aren't liquids like we consider water a liquid, more like thick soup and thicker still. As I said, there are exceptions which I will cover later. So the idea behind the restriction is that by limiting you to liquids in 100ml clear containers that will fit in a clear plastic bag, it makes it extremely difficult for any one person to build a viable explosive device by mixing the bottles together. Of course that leaves the option for several people to board the same flight and collude to bring enough liquids between each other to make a viable device. Indeed this was the cause for the ban on liquids back in 2006 [when a plot was discovered in the UK to blow aircraft up using liquid explosives]( URL_0 ). However once the ban was implemented it was felt this collusion and the act of preparing the explosives would not be able to go unnoticed on board the aircraft as the amounts allowed per person would require a high number of people and the act of mixing and creation is nowhere near as simple as mixing a cocktail! It's widely regarded in aviation circles that the ban represents the very essence of the word \"Overreaction\" but it serves another useful purpose. As I said earlier, the ban on liquids has little to do with liquid explosives. Rather than preventing the use of LBE's, it is actually a fairly effective prevention method for using liquid containers as shielded housing components for all forms of explosives, liquid or otherwise, which a liquid container would be perfect for. By preventing the containers, it makes it difficult to smuggle any kind of device through with enough explosive yield that is not immediately obvious to an airport scanner. The most common use of liquid explosive in terrorist incidents is a type of explosive called TATP (It can actually be both liquid and solid but is more often liquid). It's dangerous to make, somewhat dangerous to transport and just all round unstable after it has been stored for a certain length of time, but is easily made through commonly available materials. It's been used in practically every terrorist incident since 9/11. However as a LBE, it's not fantastic. It's also easily detectable. In fact almost all LBE components, even in unmixed form, are easily detectable. Remember me mentioning those exceptions? Here is where we come to the nightmare scenario. Professionally produced LBE's falling into the wrong hands. Some of those ARE almost the consistency of what you and I would call a liquid and better yet are waaaaaaay more powerful than anything Johnny Terrorist can produce in his bathtub. In fact some of them are weight for weight more powerful than TNT! However they still have the same problems in that most of their binary components are detectable. However the fear here is that the LBE could be masked by an outer, inert liquid somehow and because they are more powerful, less is needed. So to answer your question, the rules regarding the ban on liquids can afford to have a bit of give and take written into them when it comes to medicines because detecting and preventing LBE's involves a bit more than just banning liquids over a certain amount.",
"Did you have your name on the medicine? Basically, there has to be a little give and take, some people *need* to take liquids on a flight",
"> why are some liquids treated differently than others? This question is the easier one to answer. It's basically a trade off between laws, convenience and security. The TSA has to make an exception for medicine because there are many people out there that need more than a 1 gallon bag of liquid medicine for a trip. Additionally making them remove it from its original bottle and putting it into another unmarked bottle is just a recipe for disaster as it will no longer have instructions or labels to accompany it. So does it decrease security a bit? Yes, but it also makes the line move quicker and avoids any medical complications that may come from people trying to reorganize all their meds into new bottles, or maybe putting them into their checked luggage assuming their luggage won't be lost in an effort to be allowed to pass with them."
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8ttc7w | When watching football/soccer why can you hear the sound of the ball beeing kicked but not the players shouting/talking to eachother? | Technology | explainlikeimfive | {
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"The cocktail party effect: The cocktail party effect is the phenomenon of the brain's ability to focus one's auditory attention (an effect of selective attention in the brain) on a particular stimulus while filtering out a range of other stimuli, as when a partygoer can focus on a single conversation in a noisy room.",
"Cuz the sound of the players is mixed in with the sound of the thousands watching them... but there's only one ball making a sound.. so we hear it.",
"It's mainly down to two different pieces of technology. The first is something called a parabolic microphone. This is a microphone that can be aimed to pick up sound in a very specific area and disregard everything else around it. The other is sound filters. It's relatively easy for them to remove or lower the sounds of the crowd and the players shouting or speaking versus the ball sounds. TV stations typically remove the players shouting at each other during the game because it would likely become really annoying and is even more likely to contain swearing which is not very TV friendly. However you might occasionally hear snatches of the players speaking where the parabolic microphone aims at the wrong place briefly or the sound filter doesn't quite catch it."
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8tx0hl | Why do many gaming companies make new game engines, rather than continue to work on and improve the current one in use? | What are the reasons that a company would stop using a game engine they already have (assuming its one they built themselves) and proceed to make a new one entirely, rather than continue improving the old engine? Is there something in the old engines that prevent them from being able to continually make improvements, or is it just easier to start over and make the new engine exactly how they want from the beginning, or what? | Technology | explainlikeimfive | {
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"Isn't that what many of them still do? Improve the previous engine.",
"They usually don't. The vast majority of game companies license an engine -- mostly Unreal or Unity these days -- and do not modify it ever. A smaller number of companies create or license an engine and stick with it for decades. Even fewer companies create new engines, and almost none create new engines entirely from scratch. For instance, the id Tech 4 engine is based on the id Tech 3 engine, which was in turn based on the id Tech 2 engine. Mass Effect 1-3 all use Unreal 3 (which includes code from the original Unreal Tournament); Mass Effect Andromeda uses EA's standard in-house engine, Frostbite, because EA bought Bioware. Skyrim, Oblivion, and Morrowind all use the same game engine. The number associated with a series of engines doesn't indicate that it's a new engine. It indicates that the company thinks it made major improvements. For Unreal and id Tech, it probably means a lot of source code changed, but somewhat short of a rewrite. For Frostbite, it's a lot smaller: some big new features, some incremental improvements to the rendering engine, but everything else would probably work the same."
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8txhrn | Why must I completely shut my patchy Wi-Fi off in order for my mediocre data to kick in? Would it not be possible for them work hand in hand like super hero and sidekick to provide the fastest possible connection always? And can they not together make a stronger connection than either alone? | Technology | explainlikeimfive | {
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"Basically what happens is that Mr Wi-Fi is told to deliver a bunch of packages to your house. He delivers some of them but on one of the trips a bad guy distracts him and now he can't deliver the packages. Command center doesn't know that until suddenly they can't contact Mr Wi-Fi anymore! Now they have to finish the delivery, but they forgot what already made it to your house. It's Data Boy to the rescue! Data Boy lives on the other side of town and has to find a new way to bring you what you need. He goes to a new warehouse nearer to his house to get you everything, since Command Center forgot what they gave you. Anyways my point is; since Mr Wi-Fi and Data Boy don't start from the same place, and they can't communicate, Data Boy has to start from scratch to give you the package. . Edit: Gold! Thank you kind stranger. Edit2: a lot of people are asking why you can't have them work together. I did some digging on Google and it's time to ELI5! So as I understand it, the way it works right now is that Command Center is working hard to send things to everybody, but this is hard because they have itty bitty roads. Not only are these tiny roads, they are also tough to walk on! So right now only one hero at a time on a tiny road. Very smart people are making a nice highway so heroes and side kicks can work together, but that is very hard and they are still figuring put how to build it. Also, the highway will be easy to walk on, so normal people can walk on it too! Until we have the highway, we have to be good kids and wait for the heroes to send the packages. Source: URL_0",
"It sorta exists on Samsung phones (not sure if it is android or if it's specific to Samsung). It's called \"Download Booster\" and allows the phone to download files through WiFi and Mobile Data at the same time. It isn't for everything though, and I do remember it being very specific about the phone temperature being cool enough...",
"It's mostly because of routing. Your wifi and your mobile data represent two completely different sources on the internet and it is unlikely that their connections (even to the same site) would follow the same path. There is nothing inherent in internet protocols that would allow the two connections to be easily coordinated. This would have to happen, otherwise you'd just be downloading the same data twice, not different parts you could then assemble on the receiving end.",
"This is an option on some phones called Super download and on android there is an app for it",
"It’s already a thing. On iPhones, go into settings, cellular, and scroll all the way down to “WiFi assist”",
"this is built in to most custom roms tbh. but it consumes a lot of battery as it has to do the compiling on the phone",
"It's possible, but not easy to do because you have to somehow synchronize and combine pieces of data coming from wifi and mobile network, you can't really request half of a webpage through one and half through the other.",
"While technically possible, the complexity involved would probably not be worth the benefit. It would be two completely different connections collecting random parts of files and websites and trying to keep them straight to save the user a little time, when in most situations like that an easier solution would be to ‘move 10 feet to the left’ for a better signal.",
"Because the mobile phone is designed to give preference to Wi-Fi over data because it consumes less battery. Secondly, if you mean why can't they both work in tandem and you get double the speed, that is because networking works by keeping track of your Public IP as sender's address, to keep track of you. Also, your Wi-Fi and mobile data use different public IPs, being 2 different internet connections (they have to be unique to every user so they can be differentiated in the world\\[kinda like your home address is unique in the world\\]). So if you suddenly switch between the connections and in turn switch between the IP addresses, it is almost as if you changed houses. It would be impossible to locate you."
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8ty89q | What do cops do to prevent their guns being grabbed by someone else? | Technology | explainlikeimfive | {
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"Cop here: First, as everyone said, we use retention holsters. There are various levels of retention. Most police use Level III which means you have to bypass two different mechanical retainers to draw the weapon. We train enough to be able to draw quickly without thinking about having to bypass the retention. Most people don't know how to bypass the holster which keeps them from physically taking the gun. For example, after the Boston Bombing, the bombers murdered a police officer to get his gun. However they couldn't figure out the holster so they left it. Second, we train to not let anyone have the opportunity to put hands on our gun. We specifically train to keep someone from taking it. We're also looking for cues that people give off that they might attack. If you look, you'll also notice that police stand a certain way when talking to someone. Typically we'll stand \"bladed\" and turn our gun away from someone. Lastly, going for an officer's gun is deadly force all day. A lot of police carry backup guns or knives for this exact reason. Basically, if I'm overpowered and keep you away from my gun, I'm going to shoot or stab you until you stop.",
"Also, in addition to other answers, some holsters have more than one retention type. The holsters used by the city where I used to work (i wasn’t a cop but I was a shooting instructor) had a thumb strap, the gun had to be pushed down and then forward, and a thumb button."
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8tyfco | Why do companies limit the amount of ads you can watch? | A lot of apps offer rewards for watching ads (free premium currency, energy refill, etc). But most only let you watch a few at a time. Why? They always say "no ads available" but it's not like they actually run out. Wouldn't having you watch as many ads as possible just make them more money? | Technology | explainlikeimfive | {
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"Im no expert but I would guess that if they're giving a reward for each ad watched, they don't want you clicking through ad after ad without actually paying attention to them. Or so that you don't get too many points or whatever at the beginning and then never watch an ad again?"
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8tz49h | Why can't CPU's size (width and height, not memory size) increase? | This might be a really stupid question, but, why is Intel and AMD and huge companies like that, trying to cramp all the computing power into that small size instead of trying to increase the size of the CPU itself? | Technology | explainlikeimfive | {
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"> This might be a really stupid question, but, why is Intel and AMD and huge companies like that, trying to cramp all the computing power into that small size instead of trying to increase the size of the CPU itself? Computer engineer here, The reason why manufacturers are reluctant to create gigantic consumer chips is two-fold 1.) Defect density is a product of the manufacturing process, not the product. Every wafer has an expected number of defects per square centimetre / square inch. As the number of dies fabricated on the surface of that wafer decreases due to an increase in size, the number of defects per product increases. This results in fewer products, each with more defects that need to be handled. 2.) Power consumption and mechanical considerations. Larger chips require more rigid structural support and more elaborate cooling. This tends to scare less adventurous consumers.",
"The smaller the chip the shorter distance the dancing pixies have to go. Decreasing the time a certain request takes to complete. So basically, if it takes you 30 minutes to travel to work due to distance. If the city were to rebuild tighter it'd take you less time to get to work.",
"There’s a lot that intel will factor into the equation the biggest of which are probably cost and engineering. Increasing the size of the CPU might get less (or more I’m not sure) value than a smaller sized CPU. As far as engineering, heat becomes a really big problem. Larger CPUs are also very prone to damage and faulty parts",
"In a 3ghz processor, electric signals travel about 6cm per clock cycle. Since processors aren't laid out in straight lines (the caches in particular have to be clumped together to make sure all parts of them are within 6cm of every pipeline that needs them) this quickly restricts how large a single core of a CPU fan be. That being said, there have been computers that did what you're suggesting in a roundabout way: they put two multicore processors on a single motherboard. As it turned out, this was pointless, as anything that can be done with two CPUs on a single motherboard is better done with FPGA chips, GPUs, quantum computers, or just hundreds of CPUs on hundreds of motherboards networked together (which Amazon will rent you by the minute for a, relatively, insignificant cost)."
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8tz651 | How would a hacker break into my email account? | Technology | explainlikeimfive | {
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"1. Knowing your password. 2. Programmatically breaking your password Ex. AAA, AAB, AAC, AAD until every combination has been tried. 3. A security flaw in the email providers system allowing someone to access the database your password, and hash (code to decrypt your password) is stored in. 4. You left yourself logged in"
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8u1hjs | How do screens that you can only see when facing them from straight on work? | Such as screens used for ATMs, which you can’t see if you look from an angle to the screen | Technology | explainlikeimfive | {
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"Polarizing filters. Think of shining a flashlight beam. It comes off like a cone, right? A polarizing filter only allows certain light rays through. So picture a piece of cardboard with a narrow slit cut in it. Shine the flashlight through that. Only a little bit of the light comes out, straight through. A privacy screen only lets the light rays traveling straight ahead to come through, like its coming out of a little tiny slot. The rays off to the side and blocked by the polarization, or the “cardboard.” EDIT: The light rays that get through have to match up with the filter’s orientation axis. Think again of that sit in the cardboard. If it’s up and down, the light waves up and down get through. The waves side to side do not. The ones at an angle...only some get through."
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8u2urr | Why isn't salt water the solution to the incoming water crisis? | Technology | explainlikeimfive | {
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"At this point it’s not easy, or cheap to make salt water into fresh water, and unless someone finds a way to make it so, it won’t be a solution.",
"Purifying ocean water requires a lot of energy, and the salt has to go somewhere. You basically have to boil all the salt out of the water. Current technology requires 14 kilowatt-hours of energy to produce 1,000 gallons of desalinated seawater. That's barely a drop in the bucket for global consumption. Currently about 10 to 13 billion gallons of water are desalinated worldwide every day. This is still only about 0.2% of global water consumption. Salt water also corrodes or erodes goddamn everything it goes through, including plastics, so these desalination plants would constantly need parts replaced or repaired. As we use up existing freshwater deposits and can't replenish them, this will be one of a few feasible options, and it's probably a good one to pursue considering we already know it's possible. But it's still not economically feasible to do on a large scale right now."
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8u5cjb | Why Can't I Have two Passwords for the Same Account? | Is there a security reason for it? Or are all the assumed use cases "illegitimate" like wanting two to make a certain character not case sensitive - wanting to generate a temporary password for a trusted friend to get access without needing to create a new one and signing myself out of all my devices. | Technology | explainlikeimfive | {
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"There is no technical reason that prevents this. It's just not a popularly requested feature, because the more passwords you have on an account, the more likely an intruder can guess one of them.",
"It's extra complexity for the user, extra complexity for the developer, and worse for security. First off, you now have two different operations with passwords instead of one: change password is separated into add password and delete password. If you change your password, you need to remember to do both, and there's nothing to indicate that you . You need to give each password a name so you can keep track of them. That's extra work for you. On the developer side, most people use SQL databases. A SQL database stores data like a bunch of spreadsheets: each row is a different user, and each column is a different bit of data about that user. So there's an email column, a name column, and so forth. It's easy to put in one column for a password. It's awkward to do two or three passwords. If you want to support more than a small fixed number, you need to build a new spreadsheet, and then it's a pain to go back and forth. On the security side, let's say I get into your email account. I use that to reset your password. With multiple passwords, your old password still works, and you won't realize you have an extra password. With just one password, your existing one no longer works, so you know something is wrong. That said, there *is* at least one service that lets you do this. With Google, if you enable two-factor authentication, you can create application-specific passwords. You might make a password that only has access to your email and calendar, and then use that for an ancient email and calendar client you like, for instance."
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8u7kjj | How do ISPs connect to the internet? Can I connect on my own? | Technology | explainlikeimfive | {
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"ISPs connect to the Internet by connecting to bigger ISPs, who connect to bigger ISPs, who are big enough to connect to each other. It's a tiered system. Typically you connect to the Internet via a tier 3 provider. They pay a tier 2 provider for access to the wider Internet. And that tier 2 provider pays to connect to a tier 1 provider. Tier 1 providers don't pay each other, they just agree to connect to each other so their customers can communicate with the other companies customers. So maybe you could bypass a tier 3 provider by paying a tier 2 provider. If you are a millionaire maybe you could pay for access to a tier 1 provider. If you're a billionaire you could create your own tier 1 provider, but even then you have to deal with other ISPs because everyone else in the world is connected to their networks.",
"They have agreements with other ISPs to connect their networks with each other. They basically ARE the internet, along with other entities that have large networks, e.g. Google.",
"The ISP you deal with likely is a \"tier 3\" network in that they in turn purchase access to tier 2 networks and ISPs, who in turn connect to tier 1 networks. Conceptually you could purchase connection to a tier 2 ISP but unless you have millions of dollars to burn they probably don't even want to talk to you.",
"Sure just get cables long enough and plug into your neighbors PC. Now you have your own private internet.",
"The internet is a collection of wires (and sometimes other connections such as WiFi) that connect all computers connected to the internet together, along with some computers which direct the signals down the proper wires (called routers). ISPs own different parts of these wires collectively. Each wire is a part of the “internet,” including the one connected to your home. ISPs make deals with each other to connect their networks of wires together. ISPs don’t get the internet from somewhere, they are the internet."
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8u7qc3 | Why does everything computerised need regular software updates now opposed to older models? E.g. my Xbox One needs to update monthly(ish) while my Xbox original never did (or could). | Technology | explainlikeimfive | {
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"Security is taken more seriously than it used to, particularly on consoles that are now much more online than they used to be (online multiplayer was a much newer thing for consoles during the xbox classic generation of consoles), and that are much closer to the computers we use every day. It was unlikely that your xbox would be an infection vector for viruses onto your home network, since it was a pretty shitty computer to run anything but games on; but your xbox one is more than capable, and it's probably connected to your network constantly as well. Threats are also constantly evolving; as more of the world becomes more computerized, there's more money to be made in cybercrime, and so organized crime and even some street-level gangs are making a move into digital theft and ransomware coding to get money. And no Microsoft or Sony or Nintendo-level company wants headlines about the latest ransomware that's exclusive to their console, so they keep a stream of updates that keep everything running. The new and improved hardware also demands more complex software; more complex software means more bugs just by the very nature of coding, so bugfixes are near constant now.",
"Actually, the original Xbox DID have updates, but most people just received them via the disc, as opposed to downloading them. There weren't a whole lot of versions, though, and none provided major functionality changes. Mostly stability/anti piracy measures. If you boot up your original Xbox and look at \"About this Xbox\" on the dashboard, it'll list the dashboard/system software version. Most recent is 1.00.5960.01."
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8ua6d8 | How do refrigerators and freezers work to get cold? | Technology | explainlikeimfive | {
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"They take a fluid, called a refrigerant, with a low boiling point. They run the air inside the fridge/freezer through a heat exchanger (usually a thin metal thing designed to transfer heat between two fluids). The fluid boils from the air, and in doing so sucks a bunch of heat out of the air, making it colder. On the back side it recondenses it (to reuse it), which pushes out hot air (outside the fridge). This is also how air conditioners work, so it is basically an air conditioner in a box."
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8uaxra | What is happening when you turn electronics off and then back on when you’re troubleshooting? Phones, computers, routers... Does it matter how long you leave it off for? | Technology | explainlikeimfive | {
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"At a simple level electronics are long lists of directions that can change with different inputs. Just like when you get lost it can be worth retracing your steps to the beginning, sometimes the electronics get lost on a set of directions that don't recognize the right input to get back to the step you want. Rebooting them starts the chain of directions from the beginning (which are often the most stable directions in the system). It works on all devices because they're all doing the same thing, following a set of directions designed when they were being created. The time matters because devices have capacitors (similar to buckets of electrons) and to ensure you actually start all the directions from the top you want to wait until all the buckets are empty otherwise partially full ones might not stop following the broken branch direction.",
"Unlike many of the questions on this sub, this one actually lends itself to ELI5 instead of ELI15. Most of the answers so far have been ELI15, so let me try ELI5. Your electronics are normally pretty good at doing their job. If they're misbehaving, it's usually because they're confused about something. When you turn an electronic device off, it forgets about whatever it was it was confused about. When you turn it on again, it just gets back to doing its job, which it knows how to do pretty well. It does matter how long you turn an electronic device off for, because if you don't turn it off for long enough, it might not forget about what was confusing it. If that's the case, when you turn it on again, it'll still be confused.",
"Imagine a computer like a chalkboard; you can write things, but it takes up space. You can erase things, but you always get this leftover chalk dust. Keep this up long enough, and the color of the board is significantly lighter and you can barely read what you do write on it. So you take a washcloth to the chalkboard to remove all the chalk dust and start fresh, and the chalkboard works better. Same basic principle with rebooting a computer: Sometimes programs keep running after a fault and leave garbage in your RAM and other places, or just don't unload everything properly; sometimes a windows service in the background stops and can't restart with everything that's going on in the system. So by turning it off you force everything out of RAM, then on startup you load in the bits that run just the base operating system without any excess clutter.",
"It is returning them to a known-good state. By allowing capacitors to drain and clearing volatile memory the device can be started from a configuration which has been tested to work, compared to whatever state it might have been put into where it ran into trouble. How long it needs to be left off depends on the device, but usually 30 seconds is plenty of time for capacitors to drain and memory is usually reset within moments.",
"Am not OP but I just wanted to thank all the responders, because all the explanations were helpful, informative, and applicable!",
"I can really only speak to routers. Routers are turned off for at least 30 seconds to ensure that the cache is cleared. The cache is just the memory which holds the data being processed through the router, and it happens to be a type which requires electricity to always be running through it to maintain the information, just like RAM. Sometimes it doesn’t empty the cache correctly, so you need to drain all the electricity from the capacitors so it forgets the data which is preventing it from cleaning the cache out.",
"After lots of oversimplification, electronic devices have a set of instructions (what should it do when) and a state (what is happening right now). Instructions don't change, but state does. Mom tells you to do the shopping. Buy milk, eggs and some ham. Your instructions include how you exactly handle the action of 'doing shopping', that is 'if you want to do the shopping, go to the shop, pick products, pay, take them home' and your state is 'I should buy milk, eggs, some ham, I am still in the living room'. In the shop you realize you don't know how much ham should you exactly buy, so you just stand still and wait for your mom to call you and tell you. That's an utterly stupid thing to do, but you're just following instructions. Or you decide that ten kilograms is 'some'. Or you buy an elephant. The point is, something unexpected happened and now your state is erroneous (I am buying an unspecified amount of ham, which can't be done). When you reset a device it's an equivalent of you just teleporting home and forgetting about any shopping. Your state is now, in some sense, zero, the beginning, void. Mom has a chance to do things differently (for example tell you that you should buy 20dkg of ham) and avoid erroneous states. In case of shopping it's obvious that you can call your mom and ask. That's an equivalent of you clicking something on your PC to make it work again. But when you become a drug addict your mom would find it way easier to just void your state and try again. EDIT: The question is also about how long should it be left off. The simple answer is that it doesn't matter because the state is void the moment the device is powered off. The complex answer is that usually you don't work with one device, but a lot of them, so just because it seems like everything is off it might not be. Imagine a bunch of children that are just running around and screaming, that is malfunctioning. You want to turn them off and on - if you forget about one (when you pull the plug you basically starve the children to death, but there's always that fat kid) it might preserve its state and influence others. This means that to be absolutely sure that state is void you should wait an infinite amount of time, because you never know how fat the fat kid exactly is. But in real word things are even more complex because not all children can be simply starved to death without any consequences. The absolutely ELI5 rule of thumb is to wait five seconds."
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8ub9ai | Why do technology companies work so hard to hide UI configuration and other IU components that users are used to or expect? For example, iOS and file management, MS Windows Control Panel oversimplification or Google Maps interface w/o much customization? | Technology | explainlikeimfive | {
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"They don't want to get tech support calls from confused non-experts who accidentally changed the behavior of their system; but they don't want to totally eliminate these customization features that experts like. So they bury them where experts can still find them.",
"You are probably a much more savvy user of technology than the average person. The mere fact that you used the terms \"UI\"and \"File Management\" tells me you are probably in the top 10% (if not the top 5%) of people in terms of computer literacy. Most people don't know anywhere near as much as you do. A great number of people using these devices are pretty technologically illiterate. They are the people like my aunt, who will call me asking \"What happened to Netflix?\" when she closes her internet browser and can't remember the web address. They are people like my grandfather, who literally carried a cell phone _turned off_ for three years because he assumed it would turn on automatically when he got a call. These people **will** break things if they have access to detailed system and UI configuration, so companies do their best to make sure that users like I have described can't stumble into into those settings accidentally.",
"Because \"users\" aren't used to the UI elements you're talking about, and don't expect them. *You* expect them, but that's not the same thing. There's a reason the iPhone - the original one, in 2007 - completely transformed the smartphone market. It did away with all the twiddly little knobs and buttons and sliders of WinMo, PalmOS, Blackberry OS, and so forth; it replaced them with basically nothing. Everything either just worked or wasn't there. No decisions, no tweaking. That turns out to be what the vast majority of people want: they want it to work well enough right away, without having to spend effort, time, or money fiddling with it. Computing, as an industry, learned that lesson from Apple. Minimalism in UX design has grown more commonplace since then as companies have realized that the size of the market where people want a computing device that you just turn on and it works is orders of magnitude larger than the size of the market where people want to tinker and get everything Just So. More importantly, that larger market won't even bother to look for a way to change whatever they don't like about the product; they'll just stop using it and go somewhere else. Whereas the people coming from a traditional computing background *will* put in the effort to get something Just So. This is why Visual Studio Code, for example, has a giant json file exposing...I actually have no idea how many, but a lot of settings to be tweaked. The sort of person who writes code is generally the sort of person willing to futz with lots of tiny adjustments to get things their preferred way. /me shrugs With apologies for the car analogy, the general path of the technology's evolution is pretty parallel in this regard. You used to have easy access to (for example) adjust the fuel/air mixture and the ignition timing; you could tweak to your heart's content. But it turned out most people didn't want to have to tweak and fiddle, they'd rather just get in the car and drive. So cars have become optimized for that, and it now takes much more effort to meaningfully affect a car's fundamental performance. I don't have evidence beyond experience to go by, but it seems like that's the natural evolution of technology."
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8ubaen | Why does having WiFi turned on improve location accuracy on iPhones? | Technology | explainlikeimfive | {
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"Apple (along with several other companies) have been using iPhones and other smart devices to record the MAC addresses and locations of Wi-Fi routers for years. When you open your map with Wi-Fi active, your phone will use this information to triangulate it's location based on which networks are in range and their signal strengths, allowing it to know it's approximate location in a matter of milliseconds, long before it could acquire enough GPS sattelites for that to help. Without WiFi, it'll first ask your celltower where it is, and then refine this kilometre-resolution gradually as sattelites pass overhead. This will eventually provide decimetre accuracy, but not without running the GPS constantly for several minutes.",
"WiFi access points help to triangulate the position of a device whose WiFi is turned on. Thus, all a phone needs to do is detect various WiFi hotspots in its range, and then its location accuracy improves, because the geographical location of millions of WiFi access points can be obtained from a centralized database",
"This occurs on all smartphones. Modern location tracking isn't just GPS. As you walk around your phone is mapping the WiFi SSIDs you come into contact with. As people connect to those WiFi access points they get information on where in the world they are physically located. This means when you walk, drive, fly, whatever passed a wifi SSID even without connecting or having the password it can be cross referenced against the massive database of all users for where in space it is located. By doing this against all available SSIDs in any given spot it is possible to trianglate your position in the world even where GPS isn't available like inside a shopping centre. You will also find in addition to WiFi, Bluetooth aids in location tracking in a similar way through beacons. Beacons are small, physical devices that blast a location and request through Bluetooth, often used inside advertising signage or inside retail outlets to drive functionality in apps behind the scenes. In a similar way to WiFi, their location is mapped across the user base, so when you pass one it can be cross referenced and you can be triangulated giving even finer definition to location. There are a few other tricks that different manufacturers deploy to get location working faster and to increase definition but they vary by manufacturer and model."
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8ufxbq | How do dryer sheets work? And why is it better to not use dryer sheets for Towels? | Technology | explainlikeimfive | {
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"Dryer sheets are coated in an animal-fat base that vaporizes when heated in the dryer. That animal fat makes your towels absorbent fiber's slippery and no longer absorbent.",
"Dryer sheets help with static and it can coat the towels lessening the absorbency of the fabric. We use the dryer balls and they work much better and help dry faster but line drying is the way to go if you have the space."
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8uhy2g | How can the camera wobble whilst reniaining focus? | In the music video for shadow Moses the camera wobbles from side to side but keeps steady and the focus eg (a person) stays in the same place in the frame and still does the same action but the camera wobbles - if I'm bad at explaining please watch the video | Technology | explainlikeimfive | {
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"The video is actually using two cameras next to each other, and blending the photos in editing.",
"Can't you tell by the look in their eyes? ;O"
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8ukvdr | Why does Google Maps sometimes default to a particular route while simultaneously telling you another route is a minute or two faster? | Technology | explainlikeimfive | {
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"One thing Google tries to do (and Waze too, for that matter) is stagger drivers across different routes so that one route doesn't get too plugged up. If one route is 2 minutes faster and the routing server gave everybody that route every single time, it wouldn't be the fastest route anymore before too long. It also gives you that option because you should be able to override the decision that the routing server made for you if you so choose. And most of the time you can with no problems, if you just look at traffic conditions along that route. But that's the ultimate goal, to stagger people across different routes so as to keep the traffic flow more or less balanced (even though it will never be quite so perfect).",
"Pretty sure you can change the settings to shortest distance, fastest, no tolls, least traffic ect."
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8uogdc | Why do some Windows Updates need up to 1 hour to install, even longer than the first installation of the OS itself? | Technology | explainlikeimfive | {
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"Generally these large updates are essentially new versions of the OS, with one big exception. When you first installed the OS the computer was blank, so it was rather easy for the computer to just plop everything down and be done. Now since this is an update the computer also has to worry about making sure your setting stay the same, your files aren’t deleted, etc. which slows things down and makes it take extra time.",
"So this comes down to a few things. Since the release of windows 10, microsoft has stated that there will no longer be new versions of windows (e.g. windows 11) but there will instead be six monthly updates in march and september with 'unique' names (e.g. fall update or creators update) called 'feature updates'. Also, Instead of the security updates, they now have 'quality of life' updates which are exactly the same thing. So there's smaller updates (QOL updates, formerly security updates) and bigger updates every six months. Some of these big updates are essentially like new operating systems within windows 10 that take a long time to install. Source: Just completed windows 10 certification training. I did like 3 updates during it. They all sucked."
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8upufa | Why do low pitch bass frequencies not seem as "loud" as treble frequencies? | For example, like [this video]( URL_0 ) the bass being played is extremely loud (well over 100dB) but it seems to not bother the listeners' ears. But if it was all hi-hat like sounds/high frequencies they would sure be clutching their ears in pain. Why is this? | Technology | explainlikeimfive | {
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"Your brain doesn't perceive all frequencies at the same level. Which makes total sense if you think about it, for example the most sensitive range of hearing is around 3-5kHz which is right around the peak of baby cries. An ok-ish plot of your ears sensitivity is called the Fletcher-Munson curve which points out how low frequencies need much more energy to be perceived at the same level as higher frequencies. On top of that, for bass frequencies you don't hear it so much as feel it in your chest cavity and throat. And lastly testing bass response on people is finicky, especially indoors. There are peaks and nulls in the room where you won't hear anything just based on location. Furthermore creating low frequency sounds accurately is not cheap to do right for a test."
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8uq8dd | Why is in that in some video games, carbon fiber textures appear bent and meshy when the players’ perspective is further from it? | Technology | explainlikeimfive | {
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"If you look at carbon fibre closely, you will notice that is is like a cross hatch pattern, lots of small squares and therefore lots of straight visible lines. A monitor or TV only has so many pixels to worth with and so taking something that has many straight lines in a small space and moving them around causes the lines to shift and move. A good example of this is to stack some square Lego bricks on top of each other and then imagine they are moving around in view and off set each one off by one (like stairs). you end up with a somewhat diagonal line that has jagged edges. It's the same principle. Games try and offset this using algorithms called Anti-Aliasing. which attempts to smooth out these lines. Sometimes it works and sometimes it doesn't. Looking up how anti-aliasing works would be a good place to understand the answer to your question more."
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8ur2z7 | What is Kubernetes and how different (better) is it from traditional virtual servers running applications? | Hi, I work in tech industry so I am familiar with Virtual servers, load balancers and all but I am unable to get Kubernetes as simple as I would want to get. Can anyone ELI5 how exactly is Kubernetes different from traditions VPS (Virtual servers) offered from cloud providers (like AWS, Digital Ocean,etc.) and how is it better (considering its the next big thing coming up in Infrastrute as a Service) | Technology | explainlikeimfive | {
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"Kubernetes is a container orchestration system. There are two components to that, and both deliver value in different ways. Containerization refers to the practice of isolating software in an operating environment with lower overhead than running a full virtual machine. It takes advantage of some cool features in the Linux kernel to provide a level of isolation from the host operating system and other containers. Isolation is nice in software because you can completely control and reproduce the environment your software runs in, leading to fewer bugs in production. Because containers are so lightweight, you can ship them around as a deployable unit from your development, to staging, and eventually production environments. No matter where you run the container, you’re running the exact same system, complete with the same OS, libraries, and configuration. Now that we have this cool new abstraction, the question is how do we run it in production, in other words *orchestrate*. This is where Kubernetes and other solutions come in. Kubernetes handles the job of taking your container unit, and running it on servers operating in a cluster. The concept is pretty cool. You set up a cluster of Kubernetes nodes, and you tell the system to “run your container”, and Kubernetes will determine where to run that container. If you configure auto-scaling, Kubernetes will react to increased load by adding more containers and load balancing across them, then scale things back when load drops. It can also auto-heal, by replacing a failed container with a new one. By making the system into a lightweight deployable unit, we can really easily launch and destroy a fully reproducible application, and Kubernetes helps by giving us great features taking advantage of that core capability."
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8us1c6 | Why is one of the FCC regulations: "A device must accept any interference received, including interference that may cause undesired operation" | Technology | explainlikeimfive | {
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"Best explanation I've found came from here [ URL_0 ]( URL_1 ) Basically the device must be able to handle interference from other devices, even if the interference is strong enough to cause it to start malfunctioning, without causing any serious/dangerous failures. For example, small interference (which probably happens everywhere) will have no effect on your TV due to the case, interior shielding, etc. Stronger interference might cause the picture to start screwing up. It shouldn't blow up though...",
"There is an implied \"interference at the levels the FCC has deemed acceptable for other devices to emit\". The idea is you don't want an electric wheelchair to die in the middle of a crosswalk because someone is flying a drone nearby. The FCC rule on interference is kind of a two-way promise. Devices that create interference have to keep it below a certain threshold, and devices sensitive to interference have to be designed to continue to operate properly when experiencing that level of interference."
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8us3t1 | How does a computer chess program on lower difficulty levels decide which mistakes to make? | Technology | explainlikeimfive | {
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"While I can't talk for all computer chess programs, I made my own as part of my education so I can tell you how we did it. A serious human chess player thinks through an average of 50 or so possible moves each turn. Really good chess players have the ability to use their experience to ignore unlikely or useless moves, which allows them to trace likely moves further into the future. Computers, on the other hand, can think through *millions* of moves each second, making them almost impossible to beat. They can also be told to just not do that. If you program a computer to calculate all the possible moves for the next two turns and then pick the best one, a player able to identify and predict good moves three turns into the future will have an advantage. If you tell the computer to just take the best move on any given half-turn (say, kill rook with queen), it will play as an absolute novice (allowing your bishop to jump the queen and check mate the king) since it won't even try to calculate how you'll respond to its moves.",
"There are several ways this can be done. The most common ways are reducing the number of moves the computer can think ahead and the amount of time it can think for. Its actually a very complex mechanism that often uses a mix of these two methods and sometimes, if the game was developed very well, a profile. Certain profiles are taught to play in certain ways and prefer certain moves over others. This can either increase or decease the difficulty."
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8ustor | How do those free movie streaming sites get all of those movies? | Technology | explainlikeimfive | {
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"text": [
"It's basically a big international \"collective\" of pirates who upload the content individually to multiple sites at the same time."
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8uv4fd | Can someone explain the numbers on nvidia and AMD video cards? like why are some higher number cards worse than the lower number cards? | Technology | explainlikeimfive | {
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"The numbering scheme is arbitrary, set by the GPU manufacturer. For the past few generations, the first number number(s) have incidated the generation of the card while the latter digits ondictae where the model stands within that generations lineup. For example, Amd's 580 is a more powerful card then the 570. Both cards are part of AMD's mid-tier lineup of the 500 series of cards.",
"So generally, it's the series number first, followed by the model number. Let's take AMD. So an RX480 is a \"4\" series card, model 80. The higher model #, the more powerful the card tends to be in that generation. An RX480 is more powerful than an RX560, because the 60 model cards are lower powered, despite it being a newer architecture.",
"As somebody else said, first number (or 2 numbers) is the generation and the last 2 numbers are the level *compared to others of the same generation*. A good **rule of thumb** (not exact!) is with each generation, the cards are equivalent to one “level” higher from the old one. NVidia GTX670 = GTX 580 NVidia GTX770 = GTX 680 AMD R9 370 = R9 280 AMD RX 480 = R9 390 The newer generations are exceptions as NVidia’s jump from 9 to 10 brought a bigger improvement (GTX1070 > GTX980) and some AMD generations were disappointing (RX 580 = RX 480) but it’s still an okay approximation."
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8uwg8e | Why do new cars not have small solar panels built in standard to keep the battery charged? | Technology | explainlikeimfive | {
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"There's not really an engineering need for it on non-electric cars, and any car-sized solar panel would be far too small to provide a significant change for an electric car. There is a example of a hybrid car with a solar panel, the Fiskar Karma, and the solar panel was pretty universally panned as a useless gimmick that make the car expensive and uneconomical. Edit: here's an article about that car (it was rebranded apparently, but as the first sentence points out, still the same car) URL_0"
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8uz6hp | how do fully charged batterys when still plugged in to their charger, stop current from overflowing them? | Technology | explainlikeimfive | {
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"Phones have charging circuitry designed to help with this. But fundamentally batteries are charged by putting a voltage across them, and the current flows in until there isn't any more room for additional charge to go. The charging circuitry just monitors this process.",
"The charger is not connected directly across the battery in any modern charging arrangement. Old lead acid and NiCd chargers often were. And they relied on the fact that the voltage of the battery comes up to equal the supply voltage and there is no potential difference and no more current flowers. Modern batteries (especially Li-ion batteries) cannot tolerate being charged like this and will be damaged or explode. Now they use a MOSFET (a transistor) to switch off the connection between the charger and battery. An intergraded circuit monitors the charging characteristics (temperature, voltage, current etc) and turns the transistor on or off as needed."
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8v06k1 | why fueling an automobile can cause an explosion if its engine is running | Technology | explainlikeimfive | {
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"text": [
"It probably can't cause an explosion. In fact it probably won't even cause a fire. However the incidence of people accidentally leaving their cars in gear and plowing into pumps greatly decreases if they turn their cars off."
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8v1pyw | Why do some video games require a restart when altering the graphical settings, and other games do not? | Technology | explainlikeimfive | {
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"The ELI5 answer is simplicity. Stuff gets loaded when opening a program. If I don't want to code a way for that stuff to change while the game is open, I force a reboot. This sacrifices usability for code simplicity (or development speed).",
"Every game has to be able to load assets on startup, but changing things on the fly can sometimes take a lot more work, especially if the thing you're trying to change serves as a foundation for many other parts of the game. Sometimes the extra work for the developers is justifiable, sometimes it isn't. Sometimes you'd basically be re-loading everything anyway. For example, if you're changing texture resolution, you might want to completely re-load in order to use a more efficient memory mapping, instead of working around what you've already allocated for the old settings.",
"Source: Game designer/programmer with experience in Unity, Unreal, Allegro, SDL, and a little OpenGL. You're getting a lot of answers here, but only some of them are right for any given game/program. Every game is going to handle things differently, because every game's graphics pipeline is going to be different. One such 3D pipeline might work like this: * Game calculates (on CPU) where objects in the world are positioned * Game passes this information to the GPU * GPU calculates what part of the world can be seen from the camera, using is frustrum (imagine a pyramid with the point chopped off) * GPU draws the world, using triangles (e.g. a simple square takes two calculations -- but GPUs are really, really good at this) * GPU then re-draws to apply shaders (this can happen a lot of times if you have many shaders and/or multi-pass shaders) * GPU sends a frame to the operating system to display on the monitor Keep in mind that this process has to happen very quickly; if you're playing at 60 frames per second, you have to draw each frame in 0.01666... seconds. Dropped frames occur when it takes too long to complete part of the process. Here's a perfect example of why it's hard to get one answer for you: some games will hold off everything to finish getting that frame on screen, some will calculate what happens but stop rendering until the frame is finished. You could code it to only calculate some things, or even to throw up what you have and move on. This whole process relies on several things being in place already. For example, models (3D shapes) and textures (images \"painted\" onto the models) need to exist. Shaders need to be written, enabled, and given objects or cameras to apply to. These are, at the most basic level, just files. Textures can be png, shaders can be opened with notepad, and models can sit on your computer even if you don't have software to read them. Another major hardware component is RAM, often called memory. There difference between RAM and a hard drive is you trade out storage space for speed -- a *lot* of speed. If the operating system had to query the hard drive (even a solid state) for texture information several times a frame, we'd be playing slide shows. So we put all this data into hardware designed to move information quickly between CPU, GPU, and other programs loaded into RAM (such as the operating system), at the cost of not holding much data at once. Unfortunately, moving data from HDD/SSD to RAM happens at the speed of your HDD/SSD, because it's slower. This is why loading screen happen. Since you have so much extra work to do, you're likely going to take longer than 0.016666... seconds to draw your frame, so you get to choose between loading slowly but at good performance or loading quickly with poor performance. I know this is talking a lot about framerate instead of why the pipeline is hard to change on the fly, but we're getting there, I promise. At this point, problems start to come down to the choices of various coders. Is it acceptable to have the game stutter and choke when the player adjusts the settings? If so, the game programmer can allow those settings to change during gameplay. Simpler changes are more likely to pass this test. Is it acceptable for the engine to allow certain elements to change on the fly? If the camera is altered, does that play nice with how the engine reads the shaders and such? Questions like these are answered by a different set of programmers doing a different job. The point of an engine is to create a workspace for game programmers that flows smoothly from task to task without causing too many issues; a choice here affects how we do things there, an optimization in this area comes at the cost of tasks in that area, etc. A game programmer can change this if and only if they have the time and ability to change the engine itself. Engine programmers have to answer to graphics API programmers. The engine (and therefore the game) does not talk directly to the GPU or the operating system; these have to go through a graphics API. The engine says \"SDL, I would like a window to display my program in\" and SDL says \"give me your window size, the border details, whether you want it to be resized or not, and I'll talk to Windows for you\". The people who engineer the API have to go through a similar process as the people making the game engine. Thus, anything the graphics API can't do isn't available to the game engine or the game programmer. This goes down another level to the operating system (perhaps Windows) and the GPU's language (perhaps OpenGL). Anything those can't do trickles back to the game programmer. So, want to change how much bloom there is? Might be the shader developer made it so you can pass in a number and intensify/diminish the effect. On the other hand, might be the engine doesn't like passing in variables to shaders because that slows the pipeline, so you need to unload that shader and load in a different one. (I'd hope not, but it could happen.) This might necessitate rebooting the client. Another example is screen size. Remember when we were talking about SDL getting all the information about your game window before it made the screen? Maybe another API will let you change the window size on the fly, or maybe it doesn't. If it can't, it'll take a note somewhere (config.ini is a good friend) so it knows what to tell the API when it boots up next. These examples aren't perfect, and anyone with experience will point out the mistakes I've made (graphics programming is far from my speciality). But I hope they give you the gist of what's going on behind the scenes: there's a number of layers where programmers had to look at their options and make choices about what they would allow the next user to do. Sometimes they agree that it's ok to make the end-user wait a moment, or to sacrifice some performance t in places so they have more options. Other times they favor a smoother experience, or just don't have the tools to do what they want because of other strengths coded in. And also together, that means different options menus get handled differently.",
"There are some big changes that are difficult to make on the fly, so many game developers just say 'screw it, make the player restart the game, we don't have time for this'. Think of packing for holiday - usually it's easy to add or take one thing at the top (change the level of antialiasing), but good luck replacing the shirt that you put at the very bottom of your luggage without taking everything out (change the texture quality). Then it's just easier to repack everything.",
"Let's say that you are making a quilt with fire trucks on it. Like a rational human being, you make the fire trucks red. However after presenting the quilt to your customer they tell you that yellow fire trucks are the new hotness and so the fire trucks on the quilt absolutely MUST be yellow. Assuming that ignoring the customer isn't an option, you can do one of two things: 1) Carefully dismantle the quilt, and put it back together again with the different color. 2) Throw the entire quilt away and start from scratch. Changing graphics settings can be somewhat similar, sometimes. Depending upon how the game's architecture is built, changing a setting is easiest to accomplish by just throwing everything away and starting over - i.e. restarting the application.",
"Programming is like teaching the computer how to do things. Teaching the computer how to change graphics settings without restarting is possible, but hard. So, often programmers would rather spend their time teaching the computer how to skip cutscenes, autosave at smart times, recover from bugs, change key bindings, or all the other things that can make a game more fun to play.",
"Games that pre-allocate memory based on graphics settings and can't dynamically change that require restarts.",
"As a hardware engineer, another issue that happens is some hardware chips internal configuration can be load once die to the chips hardware limitations, or, it can't be changed while running without being left in an unpredictable state (internal registers), this is rare but happens. Its generally not this, it's that software all runs a lot of complex Multitasking operations that are not aware of what is happening on the fly, they get told how to do their job while running, if you change the configuration while the other tasks are using it they can get unpredictable results, imagine opening the fridge door then someone turns it into an oven without telling you and you reach in to grab milk"
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8v2rd0 | Is there any reason we can't make computer cases airproof and make a vacuum inside to act as a cooler? | Technology | explainlikeimfive | {
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"If my understanding is accurate, vacuum would work as an isolator, not a medium to dissipate heat. It would make your CPU radiate heat, like stars do, but the temperature on the surface would have nowhere to go making your CPU fry right away.",
"A vacuum inside would be very very bad! The components in your computer are generating heat, they need that heat to go somewhere. They use heatsinks to conduct that heat to the air which is flowing through the case and takes the heat out the back keeping everything cool We use vacuums in insulated mugs because vacuums don't conduct heat. This is great for keeping your cool item inside the mug cool, but would be very bad for anything that actively generates heat as it won't be able to get rid of it. The ISS has giant radiators that radiate the heat away into space because it cannot use heatsinks to get rid of the heat in the vacuum of space.",
"Because it's a terrible idea. When you're trying to cool something, there are four ways to do it: advection, conduction, convection and radiation. Advection is the cooling by bulk movement of a fluid. So if you're using water cooling, you pump the water along the hot part, and move it to a colder area where it can loose its heat. The 'hot part' moves to a colder area. Conduction, or diffusion, is the mechanism where the hot part transfers its heat to colder parts. When you heat up a piece of metal at one end, the heat will slowly move to the other end as well. Convection is the process where a fluid as a whole stays put, but the warmer parts of it rise, and the lower parts of it drop due to buoyancy. Think of it like a room with a bad heater in it. The warm air rises, and the cold air drops. As a result, you've got a warm ceiling, and a cold floor. Radiation is when the hot part literally emits electromagnetic radiation. The dominant frequency and intensity depend on the temperature of the object, but you can see it when a piece of metal glows red hot. It's emitting radiation which releases energy, which cools the whole thing down. When we're in a vacuum, such as in outer space, there is no air or water to move heat around. So we're left with conduction and radiation. In our case, both are viable options, since we can transfer the heat to our case, which can then use convection to get rid of the heat in the surrounding air. These ways of cooling aren't efficient enough to effectively cool your computer. In general, the bigger the surface area of the thing you want to cool, the better it cools (it's why some GPUs have fins: they drastically increase the surface area). So you'd need to increase the surface area of the cooling elements in order to get the same cooling effect. And then you'll also have to create and maintain a vacuum. But if you're already increasing the surface area, you can just as well add a tiny fan in order to pull hot air out of the case. It'll be a lot more energy efficient, and will do a better job.",
"How would the components lose their thermal energy if they’re in a vacuum? Surely it would just get REALLY hot.",
"As the others have said, the reason is that it's not efficient enough to disperse the amount of [heat that a CPU generates]( URL_1 ). In order of how much heat can be dispersed: - [thermal radiation]( URL_2 ) - all materials emit EM radiation, usually infrared, or if they are hotter, they start to glow with visible (red, yellow, white) radiation. It's not good if the CPU gets red hot or white hot, so radiation dispersion would involve a huge plate that would be barely warm, and would radiate infrared very slowly. - [convection with air]( URL_0 ) - air has a small [heat capacity]( URL_3 ) but with a fan it's possible to disperse the 30-100 watts of heat that a CPU generates into the air, raising the air temperature by quite a few degrees. - water cooling - water has a much higher heat capacity, and can cool processors down very effectively, which is why water cooling is used in high-performance computers. Ultimately, the most effective method is to use water to transport the heat from the small surface of the CPU to a large radiator outside, and then transfer the heat to the air in the atmosphere."
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8v3tbn | () Why do old tube tv's build up a layer of static on their screens after being used? | Technology | explainlikeimfive | {
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"Because the TV works by firing a constant stream of electrons at the back of the screen, where they hit the pixels and make them glow."
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8v4d8g | Why when watching soccer matches on TV is the sound of kicking the ball so clear, but you cannot hear anything the players are saying. | Technology | explainlikeimfive | {
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"[Vox has a great video on this subject]( URL_1 ) You can hear the ball sound clearly because a sound person is pointing a [parabolic mic]( URL_0 ) (big dish) at the pitch where the ball is in play and not at the athletes' heads. There are many specialty mics like this that capture the essence of a game such as a nice strike in soccer or a swish in basketball. Someone is sitting back in a production van mixing all these sounds on a soundboard to create the final product which comes out of your television."
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8v4vz1 | What is OpenGL and DirectX and what's the difference? | What are these things? | Technology | explainlikeimfive | {
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"OpenGL is a graphics library, hence GL. It's made to run on just about every system, and processes your graphics to put them on the screen. DirectX also does this, but it can also do input, sound, I think physics... It does more, but it's a Windows exclusive. Fun fact, too, that's what the X in the Xbox is for. Its original name was the directx box.",
"Think of graphics cards like countries, maybe the GeForce TI 10 series cards all speak some form of Spanish. AMD Radeon cards all speak a flavor of Russian. And so on and so forth for every graphics card type. As a developer this would be a nightmare to write games against. I'd have to have special code for each graphics card that I want to support and that means I'd have to learn many different languages. Instead, OpenGL and DirectX have done that for you. They let you speak in a single language and they handle the translations to the various languages of the graphics cards. The difference between the two was, at first, OpenGL was an open standard that worked on multiple platforms, while DirectX is a Microsoft technology and was primarily Windows only. I think that DirectX has kind of supplanted OpenGL for the most part. But in essence, they're the same thing. Just like AMD vs GeForce.",
"Designing a game engine is a lot of work and will usually take years for a graphically intensive game. In these years things such as physics and shaders are modelled and implemented, what isnt implemented though is the really low-level stuff (e.g. How the GPU - I will pretend that consoles use a GPU, even though they really use an APU which is a combination of a CPU and a GPU - handles buffers, actually produces 3D objects from vertices, etc.). These things generally don't vary much between games since they are common data structures and considering ways to implement them so different GPUs from AMD and Nvidia can use them efficiently is loads of work by itself. So instead these things are supplied in their own libraries so engine designers can use these things and safely assume they work. OpenGL and DirectX are two such libraries. As a side note, historically DirectX is a lot more but it doesn't really matter nowadays and I don't think it's what you're asking for. The difference between them is that DirectX is owned and developed by Microsoft whereas OpenGL is, as implied by the name, open-source. They will differ in performance here and there but I don't know how specifically."
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8v5342 | How Does Internet Speeds Work? | For example, my new fibre connection is supposedly at a steady 45mbps - however it took me a good 45 minutes to download a 4GB video game. Surely if there are 1000MB in a GB then it should be done in minutes... Thanks! | Technology | explainlikeimfive | {
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"Your speed is in megabits, as opposed to megabytes. It’s a marketing tactic and is misleading.",
"There are several factors here. * 1: The size of your file is measured in Giga**bytes**, while the speed of your connection is measured in Mega**bits** per second. There are 8 bits in a byte. * 2: Storage is usually measured with binary numbers while bandwidth is measured in decimal. So, 4 GB is actually 4 x 2^30 bytes (4,294,967,296 bytes). For bandwidth: 1 Kbps = 1,000 bps, 1 Mbps = 1,000 Kbps, 1 Gbps = 1,000 Mbps; for storage: 1 KB = 2^10 B, 1 MB = 2^20 B, 1 GB = 2^30 B * 3: The actual size of your 4 GB file is 4,294,967,296 bytes times 8 bits per byte which is 34,359,738,368 bits. Divide that by your speed, 45,000,000 bits per second (45 Mbps), and you get about 763.5 seconds – just under 13 minutes. * 4: There's \"overhead\" - bits of information attached to the data you're trying to download that helps the network run correctly, plus other pieces of data being sent back and forth. * 5: There are lots of places between you and the server you're downloading from that could be causing slowness or delays (or the server itself could be slowing things down). Your 45 Mbps speed just means you get up to 45 Mbps between you and your service provider. If the server is behind a 10 Mbps connection, that's going to slow you down. There's also going to be delay added each time your data has to go through another device somewhere out there on the internet, plus delay based on the physical distance the data has to travel. 6: Your connection was probably being used for other things while you were downloading the file (web browsing, your computer checking for updates, etc)."
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8v6ov9 | How do parapeligics/amputees control prosthetic arms? | Technology | explainlikeimfive | {
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"It depends. Some you can manually set positions. This used to be about as advanced ad it got. Now though they can detect muscle movement elsewhere, translating the signal into movement. Example, you lose your left arm from the elbow dow. The prosthetic detects the muscles activity in a muscle in your upper forearm. You flex it, it closes or opens the fingers with little motors."
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8v6po8 | What are smart mirrors and how are they made to be both a mirror and a touch screen display? | Like how do the pixels shine though the reflective mirror? And can I make one and how? | Technology | explainlikeimfive | {
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"They’re a bit like “one way mirrors” that let somebody see into/out of a room but not the other way around. The glass is actually *mostly* reflective and slightly transparent, no matter which way the light comes from. But the “mirror” side is well-lit, so you see more of the reflection than you see what’s on the other side (which is mostly dark). If you shine a light from the “see-through” (dark) side, some of it will actually be reflected back. But some will make it through, and can be seen from the “mirror” side. So these are just displays behind semi-transparent mirrors. When the display is off, you don’t see what’s behind the mirror because it’s dark. When it’s on, you can see the light coming through."
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8v7p6s | How does my phone "know" what company or organisation texts it? i.e. I get a message from Apple and my phone displays "Apple" | Technology | explainlikeimfive | {
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"Your phone doesn't. Usually a sender ID is sender's phone number, but it's possible to send an SMS with custom sender ID. You can read more about SMS sender ID here: URL_0"
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8v7x27 | How does YouTube determine which videos get captions and which don't? | Some videos don't even get the auto-generated ones. | Technology | explainlikeimfive | {
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"And what Dr. Suess-like program are they using to generate them?"
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8vaopt | sometimes I have to enter my debit card pin and sometimes I don’t. Why? | The price amount doesn’t matter. It’s happened both ways with $1 purchases and $100 purchases. | Technology | explainlikeimfive | {
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"You can run a debit card as credit, so you won’t have to enter a pin (but you should have to sign for large purchases). Some merchants run cards as credit for convenience sake (fast food)",
"Because they don't *have* to use your PIN, because American financial regulations are very lax."
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8vaos4 | How do long term space projects (i.e. James Webb Telescope) that take decades, deal with technological advancement implementation within the time-frame of their deployment? | The James Webb Telescope began in 1996. We've had significant advancements since then, and will probably continue to do so until it's launch in 2021. Is there a method for implementing these advancements, or is there a stage where it's "frozen" technologically? | Technology | explainlikeimfive | {
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"A bit of both. The key component of some things, like the lenses themselves, are pretty much \"locked in\" at some point. We know we can build them today, and we know we'll find a better way to build them when we actually start manufacturing them. So, how they will actually be made is up in the air but we know the size and precision needed. The next thing is that no one wants to send the newest tech into orbit - first generation things tend to break, and so when scientists discover some lighter than air nanomaterial, it's not about to make it into a satellite a week later. But in 20 years, they've definitely improved a lot. Plans would have been generally drawn up, knowing that computers would change over time, and individual components would be tested and swapped out if they can work. Each time, someone would make sure that the weight, format, reliability, and everything else will keep working as planned.",
"I was lucky enough to go to a presentation from Northrop Grumman about the JWST and someone asked that exact question. As I remember they basically said they design it to do a specific job, for a specific amount of time, so they use the tech that's available, finalise the design and that's it. They don't keep upgrading the CPU with the latest from intel just because there's now a faster one. I think that the truth is the tech is so bespoke that once they've finalized the design, they've got bigger things to worry about.",
"There is absolutely a point where it's frozen. The final major design review in most defense-style programs is the Critical Design Review. This is the point at which the system itself is fully designed (as in schematics generated, parts selected, mechanical parts designed, drawn, and analyzed). Basically after CDR, you're \"ready to build\". At that point, the system design is pretty much frozen, and any changes you make will cost you a significant amount of money, as you'll have to redesign parts of the system and basically redo the design review to show that the redesign still meets all the requirements. So, in order to meet the CDR, you really have to freeze the technology a year or two before that date, so that you can actually do the design. Design changes do happen post-CDR, but you really have to have a good reason to justify the additional cost and schedule impact. E.g. a part becomes obsolete, a vendor goes out of business and you have to find a new supplier/part, mission requirements change, etc. For the JWST, it went through various levels of CDR in 2010/2011, and the various subsystems (e.g. the science instruments) did their respective CDRs in the ~2008 time frame. So that's the timeframe you'd expect the tech to be frozen.",
"This is kinda repeating what a lot of people have already said, but often times the newest tech isn’t necessary or even preferable to older stuff. For instance the new horizon probe that was launched in 2006 was guided by a PlayStation one cpu, which was 10 years old by that time, and the next generation Orion crafts, which in theory will take humans to mars in the future, are powered by a 2002 ibm cpu. This is because they know they are reliable, and because even if there are more powerful computers, they just need one powerful enough to get the job done.",
"I think one thing that isn't mentioned in the other responses is that the things that are rapidly improving are not things that are the driving technology of the project. A super fast cpu on the satellite is not going to result in better pictures. The limit here is the lenses and recording tech. For something like the lenses/mirrors, this project is the driving force behind the tech. Developing it is the project. No one else is making these and part of this project is to push the tech. Although the tech may be \"frozen\" at a certain point in the project, any more advancements that happen are probably part of the next super telescope project.",
"Oh, I know this one! I used to work on military and NASA funded space projects. Here's a link to the broad outlines of the space acquisition process URL_0 Basically a satellite is a system of systems, with components like propulsion, telemetry, command processing, and \"science stuff\" that make up each sub-system. Throughout the lifecycle of the acquisition process different groups will meet to finalize specifics regarding the materials and technology being used. Even small things like screws and glue are heavily scrutinized. These groups form what is called a \"change advisory board\" where different members of the project get to proposed changes, discuss their impact, and vote on them . New technology is evaluated against a variety of factors that are specific to the mission at hand but generally break down along a standard set of lines; cost, schedule, and mission. Generally any change is going to impact at least two of these items and the decision of what to except and reject, regarding changes, is left to the advisory board and the projects manager. For some projects, like JWST, schedule has been a low priority . Other projects like new horizons had a higher emphasis on schedule due to external factors like launch Windows and orbital mechanics. So the answer is it depends on the specific project, but in general new technology is always considered along the way.",
"faster-than-light spaceships have it worse. the crew leaves earth one year and when they return Earth has all this crazy technology",
"They include estimated extra time to the time-frame, and some times new technology makes them push the launch even further. This is also why its really important for the scientists to follow up on the scientific papers released on a daily basis",
"For an extreme example of what happens when a much-less complicated project tries to include cutting-edge technology \"on the fly\", see the hilariously-named [Duke Nukem Forever]( URL_0 ) fiasco. TLDR: At some point, you have to just go with what you have.",
"Most tech sent to space is archaic, and with a good reason. Let’s think of it like this: What would be safer, a new Intel processor that’s just been released to the market, or an old 80’s processor that’s been tested and retested for decades. Remember, once in space, it’s very hard (and expensive) to do repairs, find bugs, and so on.",
"I don't want to intrude but.. how does this also apply to long term game development?",
"The short answer: usually \"they\" don't. A design is pretty much are locked into the technology at the point of program commitment (if the program managers are smart). Often to meet performance requirements you literally can NOT use the latest technology. The big one is the need for radiation hardening. For this reason there are still 16-bit processors being used in even new programs - the processors can handle major radiation and temperature extremes without blinking. Off-the-shelf parts can't compete even a little bit. I know of at least one program that tried to play the \"catch up game\" and the program **ended up delayed 20 years** because 1) the latest technology kept changing (faster) than the design could be completed, 2) the design could never catch up on the new design techniques required by the new technology, and 3) just as they nearly finished each design cycle, something new came along and they decided the whole thing needed to be redesigned from scratch to address the stuff that wouldn't have been finished soon enough but was still behind schedule because of the last redesign. **Anyone who's been involved in US military space systems knows EXACTLY which program I'm talking about** :-) :-). It did eventually get deployed and is still in use today. All the \"official\" histories seem to leave out the juicy parts of this. Probably for good reason. But we had a \"special\" deprecating name for the program back in the day channeling Matthew 18:6. Anyway, you generally need to and want to be very conservative when it comes to space systems because generally you can't do \"field repairs\" if you get anything wrong and the initial cost is very high so the total cost of a mistake is even higher. This is based on working on DOD space missions: I used to be an actual \"rocket scientist\"."
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8vap9q | How do they make radio commercials to play audio only through one half/quadrant of the car's speakers at a time? | Technology | explainlikeimfive | {
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"The halfs is easy, you're generally listening to Stereo audio which means there is an audio stream for the left speakers and another for the right. For many songs they're basically the same but there are several songs that make good use of this([Bohemian Rhapsody is a good example]( URL_1 )). They just send you the left Twix audio on just the left channel and the right Twix audio on just the right channel with no mixing between them Quadrants is a bit cooler. You don't just hear the sound that passes through your ear canals, you also hear sounds that pass through your skull and sinuses. Sounds that pass through your head have some frequencies slow down, some get reduced. Your brain has a map of what happens when a sound passes through your head and by emulating these changes we can make it sound like something is behind you even though there are only speakers on your left and right. Some games have started implementing this Head Related Transfer Function to give more 3D sound from just stereo speakers.([example video, you can hear the truck driving in a circle around you]( URL_0 )"
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8vbv12 | Why can't some colors on the screen be printed on the paper? | This might be one of the more mundane questions I might have, but after some Google search bringing up nothing but Illustrator or Photoshop technicalities, I figured that I would ask here: So what I like to know is: Why can't some colors in RGB be represented as CMYK? For example, pure green (R: 0, G: 255, B: 0) has no equivalent in CMYK. The brightest green in CMYK is (100, 0, 100, 0), and that is actually (R: 0, G: 150, B: 64). | Technology | explainlikeimfive | {
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"RGB is primarily for the display industry. CMYK is a print standard. When mixing inks you will always end up with a darker color than if you were mixing two lights of the same color. Furthermore, the CYMK colors are not in the exact middle of the RGB spec. This makes sense since it predates it by around 100 years. So the maximum brightness (saturation is probably the better word) is dependent on which inks are used in CYMK, but RGB does not have this limitation. This creates a smaller color gamut in CYMK.",
"Its the definiton of the colour gamut. RGB is simply defined to be different colours than CMYK URL_0",
"RGB and CMYK are standards and are defined as they are. There is nothing about the additive or subtractive color models that prevents you from having the same exact colors in each, in *theory*. However, in *practice*, by mixing inks, you can't represent as many colors as you can by lighting up pixels. The thing is with pixels, the red, green and blue lights are next do each other, and turning one on doesn't take away light from the ones next to it. With inks, it's more messy, which is why you have K for black. In theory, you should be able to just mix cyan, magenta and yellow and get black. But it's not the case due to things not being perfect, paints not overlapping perfectly, paper not distributing things evenly, and inks not being exactly the color they're supposed to be. But there are other print methods, such as Lambda printing, which is probably the best possible way to display colors. It's better than a screen, and it's better than mixing inks. Lambda printing works by exposing traditional photosensitive paper to colored laser beams and then developing it using traditional chemicals, just like in the film days. The chemicals change color based on what color light they received. There is no ink involved, and the printing process is RGB all the way. Lambda printing is the standard for printing photos professionally for higher end things like an exhibition. It's quite expensive, though the price is pretty much on par with high end inkjet printing. Inkjet has the advantages to be able to work with fluorescent colors, making it more suitable for graphics and posters, while lambda printing doesn't. Lambda printing produces more natural gradients and smoother transitions, so it's better for photos.",
"Because your screen reproduces colors by mixing *light*. Your printer reproduces colors by mixing *shades...* and it's not possible to make some colors with shades that you can make with light (and vice versa) This is truly the ELI5 explanation, but white light is made up of all colors of visible light, basically all the different wavelengths of light mixed together. Now the reason things have different colors is because they absorb certain wavelengths of light and reflect others: The reason grass is green is because its surface absorbs all the other colors of light and only reflects green. So, each pixel on your monitor is three light sources...think of each pixel as a red, green and blue flashlight all next to each other. If you want white, you turn all three on, because when you mix red green and blue light, you get white. But, if you tried to print that, if you mix red, green and blue paint, you don't get white, you get a sort of greyish-green color. So, when you print something, your computer has to work out how to mix Cyan, Yellow, Magenta and Black pigment to match the same color you get from mixing red, green and blue light. Some specific colors just don't have an equivalent."
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8vdoa1 | Why does the selfie cam flip the picture? Cant it just take a normal picture like the front camera? | Technology | explainlikeimfive | {
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"It's for usability. When the camera is facing you, a lot of people find it more intuitive if it behaves like a mirror instead of a camera. People are used to handling mirrors, so it just winds up being more comfortable for the majority of users. A lot of phones will also let you set whether the image is flipped or not."
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8vep5s | Why can authorities seize the .se ccTLD for The Pirate Bay but not the .org gTLD? | Technology | explainlikeimfive | {
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"Different TLDs follow different countries' rules. In both Sweden and the US, the government isn't allowed to arbitrarily seize domain names- they have to follow some procedure, probably involving the courts, to do so. Swedish law and legal procedure allowed the government to get an order to seize the .se domain. US laws did not allow them to seize the .org domain.",
"Ultimately Swedish law recognised the business of providing magnet links to torrents for the purpose of piracy to be illegal, and allowed seizure of the domain. US law found that distributing magnet links, as they're not copyrighted material themselves (even if they exist to allow access to it) is legal so the .org domain was safe."
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8vf6ov | How do the light up wristbands at concerts and sporting events synchronize perfectly? | Technology | explainlikeimfive | {
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"For a five year old: Generally, they use infrared (invisible) control signals. Just like a remote that controls a TV, there are similar devices high up above the event that send control signals to all of the wristbands.The lighting designer can decide which parts of the audience show up as what colors, whether they flash, fade, etc. Just like adjusting the volume of a TV, the lighting designer can adjust what happens on all of the bracelets. The designer usually can’t control each bracelet on its own, and instead controls them as big groups, based on seating area. Like you’re older than five: High up in the rigging of the show/stadium they have lots and lots of infrared emitters that “paint” invisible control patterns over the spectators. These emitters can even be built into small handheld devices that allow on-stage talent to wave a “magic wand” to make the audiences lights react. PixMob is one of several companies that does this, and they now have some pretty sophisticated ways to shape the infrared control signals. There are also ways to control the bands via RF/NFC control, but it’s dramatically more complex and not very cost effective for massive deployments. Source: Am a very happy multi-year customer of PixMob."
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8vgnc3 | how are we set to release 5G soon if we haven't acheived true 4G? | Technology | explainlikeimfive | {
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"Just because they've standardized the protocols and started designing equipment doesn't mean that companies are going to upgrade their equipment overnight. It takes *years* to do all the designing & testing of the equipment, get it certified, start manufacturing equipment & then start rolling out those sorts of *massive* infrastructure upgrades.",
"5G Is completely different to 4G - 4G was essentially the same as 3G but bigger and better. Bigger pipes allowed better speed and capacity. 5G allows for much more intelligent use of network capacity, such as being attached to multiple cells at once and being able to make one call or data session. We haven't had the ability to do that in the past and it effectively gives us a massive advantage in load balancing traffic. 4G will continue to be developed, in the same way as 2G kit still plays a part in modern networks, and is still subject to upgrades and optimisation. It's just the developments had been to allow the big changes that warrant the 5G status, and it can be argued that these are all changes that we need as soon as possible",
"How many Gs do we need and when will we know when there can’t be anymore Gs to be had?",
"What do you mean? There are technologies out there that support true 4G and coworkers of mine built demonstrators using 5G already. Just because it isn't being used commercially yet doesn't mean that the next step can't be researched.",
"Welcome to Mobile Network marketing where the speed classifications are made up and real world results don't matter.",
"One big hurdle for 5G is the coverage area of 300 metres from transmission site. The backhaul infrastructure upgrades required are significant. Areas with existing fiber to the home coverage will be far more efficient to transition, for this reason it will likely be slow to be fully deployed nationwide in US.",
"The standard starts with a wild milestone that shows the path technology should progress at. Also it just states what the technology is theoretically capable of. What is important between the standards is the implementation or the changes it brings. This could be a change in modulation or the protocol that is used.",
"What do you mean 5g means fifth generation. It's not one technology or speed ( ok there are somr standards, but it's not like saying 5gb/s or anything) Think of it more like video game consoles. PlayStation and Nintendo and Xbox all release consoles roughly about the same time as the same \"generation\" of console. But that doesn't mean they all have the same speeds or specs. And one company could be ready to release their next generation console soon after the last console of the previous generation. Or think of it like people generations. The last person in the millennial generation isn't far off from the first person in the next generation, but we still divide people into generations based on years they were born",
"(forgot to mention this is an HFC standard, so it's not pure fiber. Fiber to the distribution nodes, COAX (copper) to the homes) I work for an ISP, and I can draw a pretty good picture of how it works in that field at least. We're about to launch DOCSIS 3.1, which supports 5 gigabit connections in the home. The network has slowly been improved to support 10gb to distribution nodes, so we can deliver 1gb to each home connected to it. Our previous best case was theoretically 500mb, but the highest I've seen used on the line is 350/20. It's pretty rare that we see connections where this works optimally, but it's becoming the norm. Because of the difference in network quality ranging from state of the art to 1980s analog tv technology, there is a vast difference in performance, and so we are keeping the new modems and lines at least a little close to heart because we don't want to make the masses think we will have 1gb very soon. The same can be applied here. It will start out small with 5g, even though 4g is not everywhere yet, and it will be the focus of manufacturing once the standard is broad enough to be marketable. TL;DR - Shit's not done, but we still tryna innovate, ya dig? PS: What I said about DOCSIS 3.1 is not confidential. I work for GET, and there have been articles about it in tech news aggregators already, so no sense in thinking I just dropped a bombshell on the locals."
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8vgw4q | Why are 'bits' used instead of 'bytes' occasionally to describe computer storage or transfer speeds? | Is it literally just to make download speeds/hard drive capacities seem better to the layman? E.G. Internet companies sell 100mbps connections which can't get anywhere close to 100 megabytes/s | Technology | explainlikeimfive | {
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"Tradition. Network engineers care about moving bits around. You can let somebody on the other side figure out what they mean. You'll also often see things like I/O bus speeds measured in bits (or \"transfers\") per second for similar reasons. The people writing software & making data storage devices, OTOH, tend to care about what those bits *actually mean* so they think about the data organized into bytes. A lot of people might say that ISPs advertise speeds in terms of bits to make their products look faster but the convention goes back long before PCs and networking were widespread consumer products. The original Ethernet was a 3Mbit/s standard. Early modems were rated in terms of \"baud\" (bits of audio data per second) - with early examples being as low as 110 and 300 baud.",
"It doesn't happen occasionally at all, it has been the convention since forever. back in the early days of computing a bit is a bit is a bit, but depending on the machine architecture a byte wasn't always a byte when comparing two different machines. For example on your standard intel based machine of today 1 byte=8bits, but on a pdp8 from the 60's 1 byte = 6 bits. Even today on many embedded systems you have different sized bytes. So working in bits is just safer. The other guy who responded saying it has something to do with marketing is completely wrong.",
"It's just a matter of conventions. Bandwidth is measured in bits per second while storage is measured in bytes. When it comes to kilobytes, megabytes and so on you have two standards the SI one and the binary one. The SI one uses 1000 as the multipllier while the binary one that your OS cares about uses 2^10 i.e. 1024. The advertised space in storage drives is in the SI standard not the binary one so you end up seeing less space when you actually use the drive.",
"The byte is a relatively recent invention, and not at all as commonly used as you probably think. There used to be computers running all sorts of different numbers of bits to a byte. The old SMS protocol for sending text messages over the cell network didn't use the 8 bit bytes we're used to, but a custom 7 bit character. If there's a limit to how many characters you can send in a message, it still does, even if your phone is able to pack Unicode characters into it. Most modern computers store all information 32 bits at a time. Even single-bit Boolean values are given an entire 32 bit block of RAM since it simply isn't worth packing them any tighter than that, and unless a programmer goes out of his way to change it, that's how they're sent over the internet (along with an IP address and packet header). Last I heard, French developers still referred to bytes as octets, though this was about a decade ago. Bits, on the other hand, had become essentially globally standardized by the time the internet was invented, so they can be used to measure speed without worrying about what hardware someone is using. (I'm sure there's still someone, somewhere, working on making non-binary bits)",
"A byte of data in storage is 8 bits, but transfer protocols often include extra bits and bytes for synchronization, error-checking, security, etc. Your internet company can say \"our switches and wires support 100mbps,\" but they can't guarantee what specific protocol will be used to communicate between you and someone else. Just as an example: Bluetooth Low Energy has a bit-rate of 1Mbps. Protocol version 4.1 can use 14 bytes (112 bits) just in overhead for addressing, security, and error-checking in order to send a message of 0-32 bytes (0-256 bits)."
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8vgwnz | How do phones like the Samsung Galaxy S9 & Razer Phone reduce the resolution without any change in display size? | For example, on any other phone, if we change the resolution, the sizing of the contents get changed, but on the SGS9, the sizing remains the same. | Technology | explainlikeimfive | {
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"Just like computer monitors do - the device interpolates the pixels of the image. In other words, rather than a 1-to-1 mapping of pixels, each pixel takes on some of the color of nearby pixels. There's no reason why other phones can't do this, as it's really just a matter of software. But interpolating the pixels results in a blurrier image. This is why you should always use your screen in its native resolution. And this is probably also why some phone manufacturers choose to just shrink down the content if you change the resolution, since this maintains a 1-to-1 pixel mapping.",
"Havent checked for the particular phones, but my guess is screen scaling. In ELI5 words (as it is this reddit afterall) you address multiple pixels as one, e.g. if going from 4K to Full HD (1920x1080) then you adress 4 pixels in a square as one. Now this would indeed create bigger images if the source material is the same (I.e. still 4k). In order to preserve the size we'd have to change the DPI (dots per inch, or pixel density) we can do this by simply throwing away 3 out of 4 pixels or use a bit more sophisticated methods like taking the average of every 4 \"source-pixels\" and turn that into 1 \"new-pixel\". By downscaling both the video material and the display resolution you preserve the actual displayed size. Usually you want to do the oppositte tho, in order to render at a higher resolution (capture more detail) than your monitor allows and then scale back down to still display on your screen, ofcourse with a proper \"throw-away\" method to preserve as much edges as possible. I assume that they want to do this in a phone to save power, as you'd probably get away with deactivatong 75% of a 4K phone display, except when looking at it very closely."
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8vhn9x | What is the difference between electronic and digital signatures? | I'm going to become paperless, but I can't understand the real difference between the two types of signatures. | Technology | explainlikeimfive | {
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"Well, first of all - they are indeed not the same thing and the confusion is quite wide-spread. The term **“electronic signature”** as by ESIGN Act (US federal law about the use of electronic records and electronic signatures) means pretty-much any electronic manifestation of intent/consent, for example a tick in Terms & Conditions checkbox, an image of a handwritten signature or a name in the end of the email. A **digital signature** is actually a type of electronic signature that uses cryptography to sign documents and uniquely associate them with signers normally with the help of digital certificates. It means each signer needs to have a digital certificate so that to be linked to the document and to be identified. There are various options to get these certificates, for example from the Certificate Authority or even from the government institutions - they are obliged to guaranteed person’s identity. Basically, electronic signature is showing your intent to do something, like signing a contract, accepting terms or do business electronically. Digital signatures is about person’s authentication and proving that you are who you say you are. For a user, both electronic and digital signature looks quite similar. But digital signature have a lot of cryptographic action under the hood that binds the information to the person. Hope this helps! Materials used to answer this question: [ URL_1 ]( URL_1 ) [ URL_2 ]( URL_2 ) \\- actually a quiz with answers [ URL_0 ]( URL_0 ) [ URL_3 ]( URL_3 )"
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"https://blog.keepsolid.com/digital-signature-vs-electronic-signature/",
"https://keepsolid.typeform.com/to/bLeOyM",
"https://blog.getsigneasy.com/electronic-signature-101/esign-vs-digital-sign/"
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8vlqcd | Why is it more challenging to store renewable energy than other forms of energy? (Ie. Why has storing renewable energy been a challenge, and hence, seemingly become the new measurement of milestones with regards to renewable energy?) | Technology | explainlikeimfive | {
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"Electricity storage is the challenge. Batteries, in the capacity needed to store enough to power houses much less cities, can get very expensive. Many sources of renewable energy are far from consistent and not controllable like burning fuels, so storage is a huge aspect of electricity production if renewable sources are to compose a significant portion of production"
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8vm8gq | How are Operating Systems created? | Languages, Programs, etc. are built on Operating Systems, but how is an Operating System made? An individual has the parts for a computer, but what did the pioneers of Personal Computers do to build up their OS’s. | Technology | explainlikeimfive | {
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"The earliest OSes would have been written by hand (in machine language!) and manually entered into the computer's memory by way of a series of switches on the front panel. You'd do just enough of this to get the computer running enough to read more code from another device - paper tape, punch cards, a keyboard, etc. (which also contained hand-written code but it would be much easier to work with) Once you get this up and running, you can use this system to develop a more robust OS, an assembler, higher level languages and so on. Repeat this cycle until you've got something that's properly usable. Once you have *that* running, you can start using that computer to write the development tools for *the next* OS - even if it's on other hardware. Nobody needs to start *everything* from scratch anymore unless they're doing it for the entertainment or educational value of it.",
"Most operating systems are written in the C language, afaik. Before we had operating systems, we had operators. People who's job was to physically load in punchcards with whatever code we wanted to execute, starting with the driver for whatever system the computer used to return a result. This changed when someone though to put a small, battery powered chip in the computer, which would always be on and would load the driver for whatever the operating system was stored in.",
"Languages aren't built on operating systems. Operating Systems are just computer programs used to run other computer programs, they aren't particularly special in any sense. You write an operating system just like any other program, in any language that can be compiled to machine code. The only difference is that you need to store it in a specific place so the computer knows to load that program when it first starts up but that's handled by the installer. On the earliest computers, you would program computers by wiring up switches manually or by punching holes in paper cards (allowing switches to connect as the holes scrolled by). Those computers didn't have operating systems- they could only run one program at a time, and they'd run whatever you put in when the computer started up. Early operating systems could be programmed using those OS-less computers."
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8vmth0 | used motor oil recycling | So I have a few cars and when I change the oil I always take my used oil to the AutoZone for recycling. I see they pour it into a giant dumpster on wheels looking thing, but what happens to it after that? Exactly how do they separate the different oil weights that are now mixed up and how do they remove all the dirt and what happens to the dirt after that? | Technology | explainlikeimfive | {
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"It isn't recycled into new motor oil. It's re-used in refineries to make heavier petroleum products like fuel oil, asphalt, etc. Refineries designed to handle even the lightest crude oils have no problem with mixed lubricating oil or a little dirt and grime that might be in it."
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8vpd88 | How does cutting two fiber lines cause issues along the whole east coast and why does the traffic not take alternate routes when it occurs? | Technology | explainlikeimfive | {
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"On a well-designed IP network, yes, the traffic simply takes alternate routes. Part of the beauty of how Internet routing works. But it would appear that Comcast did not have enough redundant lines to handle its traffic in this region.",
"A couple things come to mind looking at what details I can find. First, note that fiber conduits can carry hundreds of circuits in total, so cutting \"two lines\" probably means dozens of Comcast circuits went down. Second, it looks like one of the circuits was going West out to Chicago, the other going South to the Carolinas. If you start in the Northeast and cut the lines south and west, you don't have a lot of options left. Furthermore, this was two different carriers with fiber cuts at the same time. If you ask \"why can't they have three paths instead of two,\" well, of course you can if you want, but what is the additional cost, and what are the chances of two providers having cuts on the exact circuits that would cause an outage at the exact same time? Obviously it happened, but chances are low and costs are high, so it's often not worth it. Now, I don't know of all the details of how Comcast's network works, exactly what failed, etc, but let's look at a hypothetical situation where New York is a major hub, and it has connections to other major hubs, say Chicago and Atlanta. So we have those dual redundant connections, we'll say they are 200-gigabit connections. Then we have minor hubs. Maybe Buffalo or something--it has dual redundant connections as well, in this case we'll say to Chicago and New York. Since it's a minor hub, maybe those are 40-gig connections. So we lose New York to both Atlanta and Chicago. Depending on circuit paths, maybe we lose one of the Buffalo circuits, maybe not. But even if we don't, we can't carry all of New York's traffic over the Buffalo circuit, it's just not big enough."
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8vr9x1 | How do they make clean rooms super clean? | I was looking at this picture posted elsewhere ( URL_0 ) and started wondering how they make the clean rooms themselves so ultra clean after construction. NASA and chip manufacturers must have them, but whats the procedure? How often are they recleaned, and do they need to haul everything out during this? | Technology | explainlikeimfive | {
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"As much as I understand is that they have crazy air filters. Plus everything that goes in gets cleaned, everyone that gets in is being sucked off from dust before entering. I know one of the methods to clean the air from dust is with electric charge that \"pulls\" the dust like a magnet.",
"There are a few things. To start off, some definition: clean rooms (for technology, not medical) refer to particle counts - basically the amount of dust or other particulate in the air. Clean rooms have classes, which refer to their particle count - a class 100,000 clean room is the lowest (and only marginally better than a normal room), then you have class 10,000, 1,000, and 100. The number refers to the maximum number of particles per ~~square~~ cubic meter the room has. First as other people have mentioned, the air circulation systems have crazy filters in order to reduce particles in the air. This is the main way that clean rooms are \"cleaned\" - even if you have dirty, dusty air inside the room if you have an industrial strength clean room certified HVAC circulating the air in an enclosed environment it'll eventually get pretty low. The other big concern for clean rooms are sources of particles. There are tons of everyday objects where little tiny specks or flakes will rub off for normal use. Things like paper, most types of cloth, carpet, ceiling tiles, paint, wooden tables, people, etc. all will give off particles over time. High class clean rooms will significantly restrict what can be brought inside. For example, things like paper and pencils can't go into high end clean rooms. The ceiling tiles need to be special so they don't shed particles over time. The paint in the room has to be special. The room will typically have hard tile floors that are waxed so any particles that do enter the room cling to the floor and are mopped away regularly. Those suits that people wear prevent normal clothing, hair, and skin cells from entering the air in large quantities. Typically it is much easier to keep a clean room clean than it is to re-clean one. If some construction or work needs to happen in the room they'll need to cover or preserve anything in the room that's sensitive, do the work, and then go through and clean all surfaces they can while letting the HVAC circulate the air and filter out the particles. Typically this is only done when absolutely necessary.",
"In addition to the filtering that other posters have mentioned, most really clean rooms use a technique called laminar air flow. The idea here is that air in the clean room is continuously flowing from the ceiling to the floor, with basically no horizontal motion. Any particles that are generated get pushed to the floor without contaminating things around it.",
"There are filters in the ceiling that you can see in the photo, the air comes through the filters, down through vents in the floor and is re-circulated up the inside of the walls and back to the filters. It is this action that cleans the air, and the room is maintained above atmospheric pressure to help push out any contaminants and to prevent contaminants being pulled in. Any person entering the room has to wear special suits to prevent people making the air dirty and any equipment is cleaned on entry, additionally the room is cleaned daily to remove any dirt that has managed to get in"
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8vw7ii | How does the size of screen (eg 40") and resolution (eg 800x420) affect each other? | Technology | explainlikeimfive | {
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"The physical size of the screen will change the pixel density (ratio of number of pixels to the area of the surface they occupy). Lets say your projector can project an image anywhere from 32 inches all the way to 100 inches. At 100 inches, your 800x420 resolution would be much less dense, causing it to look more pixellated and jaggy. Shrink that down to 32 inches, and you increase the pixel density, causing the image to look relatively sharper. Obviously it would look even better if the projector had a native resolution of 1280x720 (720p), but the smaller you can shrink the display area, the better. Hope this helps!"
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8vw9fl | How do computers and games handle wheels and rounded objects? | Ok so I remember vaguely from some high school math class that mathematically due to numbers being infinite that walking is impossible due to the numbers and fractions your legs bend and swing will go through an infinite number of greater and greater fractions. (I'm not sure If I made that up or it's a real saying I remember but sounds about right.) So how does animations and video games that rely solely on mathematical calculations, deal with legs moving or ropes swinging or round objects at all? | Technology | explainlikeimfive | {
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"Typically they are drawn as a large series of tiny triangles, enough to fool the eye. But the physics equations are based on the real round objects.",
"Sounds like you're thinking about Zeno's paradoxes, specifically the [dichotomy paradox]( URL_0 ). It's not really an issue in computer simulations like games because they normally use discrete time-steps. Say if an object O is moving from point A to point B at velocity V, a game that is running at 60fps doesn't continuously calculate O's position but does so only at 1/60=0.0167 second intervals. So O's position is calculated as A+V\\*Frame\\*0.0167 at each step of the simulation. Sometimes collisions are only considered to occur if objects intersect at one of those time-steps, sometimes the calculations are a bit more sophisticated."
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8vz618 | How does the crew of a show/movie film a scene where a character looks straight into the mirror, and we can see the mirror head on without the camera being seen? | Like in the Truman Show, where he drew on the mirrors. I just don’t understand the technology behind it. | Technology | explainlikeimfive | {
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"The mirror is angled so that the character is not looking at himself, but at the camera. Thus the camera is looking at the character.",
"* the mirror is at slight angle so it only looks like it is head on * there is no mirror, you are just looking at the actor head on through a fake mirror * there are two actors, the real one in the mirror, and a double that you only see the back of * CGI is used to add a second image or remove the camera",
"In john wick 2 there were mirrors everywhere. The crew didn't bother hiding for the most part. The vfx artists would clean up the camera and crew by using a combination of digital paint, CGI (rendering the room and proper reflections), clean plates shot on set (by the film crew) or time offset patching with tons of help from match move artists (recreating the camera movement in 3D). I know some people who worked on it and they almost went insane. 60-80 hour weeks."
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8w1ti8 | what is MIDI and how is it used? | Technology | explainlikeimfive | {
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"[Wikipedia article]( URL_0 ). It's a set of standards (computer software, cables / connectors, etc.) for connecting musical instruments to a computer, in order to record or create music. You always have the option of using a microphone next to an acoustic instrument to record it, but this would result in recording the \"sound\" (.wav file) rather than the \"notes.\" The MIDI interface records the notes; you can connect a MIDI keyboard or MIDI guitar and play the notes you want, and the computer can then change the \"sound\" of the notes from violin to piano to drums to synth / electronic, whatever you want. This lets you use a keyboard (for example) to first record the drum beats, then record the bass guitar over the drum beats, then add piano, violin, guitar, whatever; basically you can create a full symphony or full song with just a keyboard - you don't need all the instruments that an orchestra needs.",
"It transports signals regarding device information (key strokes, knob control, buttons, foot pedals) between machines. Usually the signals travel from a controller to a computer that interpets them. USB has taken it's place in most modern equipment."
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8w2wal | Please help me understand cloud storage such as GoogleDrive | I'd like to free up a bunch of disk space on my PC but still have access to the files, I'm not sure if cloud storage is the answer. I don't really understand it -I'm not very good with technology at all. Could I upload a bunch of files onto google drive and then delete those files off my PC and have access to them from a cloud? would that free up space or would it just create another copy or something. Is it's purpose just to share access to files while still having a hard copy? | Technology | explainlikeimfive | {
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"The \"Cloud\" is really just a nickname for remote server storage. Right now, you have the file on your hard drive on your computer. When you \"upload it to the cloud\", you're just making a copy of that file on someone else's computer (in this case, Google's, and it's not a desktop computer but a massive server farm). Yes, you can upload your files to Google's service and then delete them from your hard drive and still have access to the files and free up space on your computer. The two big risks here are that someone gains access to your Google account and subsequently whatever information you have stored there (not necessarily too likely, especially if you have a good password and use two factor authentication) and the service you choose goes out of business (also not very likely in the case of Google). Also, you can view the documents through Google's service, and you can edit *some* of the documents online (if they are text documents or spreadsheets, for instance), but you can't edit/modify all types of files. That means that if you want to edit photographs you will have to download them to your computer again to do so, since Google doesn't have online photo editing (or if it does, it's very basic).",
"Imagine cloud storage as a flash drive that you can access from anywhere, without the risk of damage/loss to the drive itself.. Do with it what you please. If you want to store a few larger files and delete the local copies, you can.",
"Imagine your computer to be a large cabinet, and all of your files to be paper documents. Whether they're spreadhseets, notes, letters, pitctures... it doesn't matter. When you want to look at some picture, you take it out of the cabinet, and look at it. When you're done with it, you put it back. After a while, your cabinet starts to get pretty full (or you fear a fire may start, and you lose all of your stuff), so you ask a buddy of yours, who you know has a lot of cabinets to put stuff in, if you can store some of your stuff at his place. Let's call this guy G. Oogle. Now, you don't want to drive all the way to Oogle's place every time you want add or remove some files, so you set up a system where you fax him the stuff you want stored, and he faxes you the stuff you want. This works pretty well, and Oogle is a kind man, so he offers the same services to other people as well. He's got a lot of space to put it all, so why not. He may even build a couple more cabinets. Of course, Oogle isn't dumb. He knows that it's possible that he may accidentally throw a file in the trash that people still need. Or there could be a fire, or a cabinet could collapse, making all files in it unreadable (I admit, it isn't a perfect analogy, but I hope it works). So he buys another home, in some other location. And maybe a third, and a fourth. And then he basically does the same with those other houses as he does with you. And for each file in his cabinets, he'll ask one or two other houses he owns to put it in their cabinets as well. Similarly, if they get a document, they ask other houses to store it as well. Now he can lose an entire house, and he'll still have all of the documents needed. Nonetheless, it can be possible that through some fluke, all files get destroyed, but Mr. Oogle is always very careful to minimize this chance. Another fun thing, is that because Mr. Oogle has the file in multiple locations, he can also ask those to help him out if he's getting a lot of requests at his original house. If he has 5 fax machines, then he can only send 5 files at once. So if you want to look at that cute picture of your dog, but you're the 6th to call, you'll have to wait until one of the lines is open. But if Mr. Oogle calls his pals, and tells them \"Yo, I've got someone waiting for that cute picture of their dog. Can you handle that, I'm kind of busy here.\", they can help you out, and you don't have to wait (as long). I hope the analogy made sense, but I'll give a short recap here. You can store your files locally, but because you want a backup, or you just want to make more space on your computer, you decide to upload some of it to \"the cloud\". This means that you're basically asking someone else (in this case Google) to store it for you. Of course, Google also has backups and redundancies, in case a server (read: computer) fails, or if an entire server farm (building of servers) gets destroyed. There's also a bunch of other stuff going on, that I briefly touched, so that you can get your files pretty quickly. One of those is load-balancing, where Google distributes incoming traffic from all over to other servers, so that you can get your files without too much hassle.",
"Thank you guys for the explanation, very helpful!"
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8w43qi | Despite living in a digital world, where our electronic services celebrate no holidays... How my bank can delay my pay on a holiday? | Technology | explainlikeimfive | {
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"Because there’s no one at the bank to process or check the payments and deposits and whatnot. And no one at the issuing bank to verify the money being sent out.",
"The simple answer to that is that the bank doesn’t want to transfer the money. They can hold the money for a few days so they can use your money for longer. The tranfers from bank to bank used to take time in the past because someone had to literally grab the money from the safe and take it to another bank, so they use that habit now even though it’s all computer work. Banks do bussiness with your money while it’s in your bank account, so holding to your money for a few days gives them time to invest it and make more money."
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8w51pn | Why is it that sometimes one volume of something sounds right but when you try to listen to something at that volume again, it is too loud or too quiet? | Technology | explainlikeimfive | {
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"In my experience, one’s awareness and cognitive state or mood comes into play. Interestingly, when I take stimulant medications music sound much louder and clearer than when I'm not on the medication. The mind also can 'ignore' noises after a period of time listening to them. In the same way we can block out white noise or people talking in a bar."
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8waof2 | the difference between IaaS (infrastructure as a service) and PaaS (platform as a service) | I have a specific situation. We have 1 ERP System 1 cloud service model 1 App Information from the ERP should transfer to the App through the cloud. What should the cloud service model be IaaS or PaaS? Is the connector an API or EDI or both? What would be the case if instead of an ERP System there is a Web EDI with its own cloud? I am very lost and got super confused. I've been trying to understand all of it for weeks, but i can't seem to wrap my head around it. | Technology | explainlikeimfive | {
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"IaaS provides you with a plot of land, an electric, water, and sewer hookup. PaaS provides you with a house ready to live in. You just need to put your furniture in it. In this case, is your App running on an existing software solution like a tomcat? And someone else is managing that tomcat? Or do you need to install the App on a base OS installation and only need the bare bones?"
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8wbppf | Why are user names not case sensitive? | ELI5: Why are passwords case sensitive and user names or email addresses are not case sensitive? In other words, why are user names not case sensitive? Is the technology for each different? | Technology | explainlikeimfive | {
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"In situations where the username is used as a displayed name, case sensitive usernames would enable someone to attempt to impersonate someone else just by registering a new account with a different permutation of capital/lowercase letters. The same applies for web domains. For emails, case sensitive addresses would result in a lot of undelivered emails from someone forgetting which letters were capitalized or not. Etc. Also worth noting that some companies, like Wells Fargo, do not use case sensitive passwords as an added convenience to the user. For passwords, passwords are supposed to be arbitrary, are not stored in plain text or ever displayed, and allowing case sensitive passwords enables a massively wider range of possible passwords to discourage guessing.",
"I'm probably going to get corrected on this, but there's nothing universal to either. You can have a password system that isn't case sensitive and you can have a username/email system that is. It's usually implemented this way because case sensitive passwords are substantially more secure.",
"Its a design choice. You could make a system that allows casesensitive names. Other awnsers have discribed why that is not a good idea."
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8wc1e3 | Why do companies provide open source software? What is the benefit of providing free software when you could be making money? | Technology | explainlikeimfive | {
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"Open Source Software (OSS) is known for providing security advantages, because many more developers are working on and looking at the code at the same time, versus a proprietary software where the source code is closed source. Many companies will embrace this by releasing a \"Community\" version of their software, and having an \"Enterprise\" version, possibly with advanced features. The companies will, in these cases, make money by selling hosting and support for the product, instead of just selling the product itself."
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8wcg4y | When something needs two or more batteries, why do they have to be out in in opposite directions? | Technology | explainlikeimfive | {
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"Many devices require batteries to be wired in series (ie opposite ends connected) so that a higher voltage can be obtained. Placing batteries in alternating directions enables the connection between batteries to be a short metal strip as opposed to a longer strip or wire crossing the length of each battery. The former is a bit cheaper to construct and adds a barely noticeable inconvenience to the user.",
"Technically they don't, its just easier from a design perspective. Each battery has a positive and negative end. Electrons come out of one and go to the other. But that direction is set. So to make them face the same way you need to run a long wire from the top of one battery bottom of the one next to them. If you face the opposite direction then that wire is really short and easy. So that is why they usually do it that way."
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8wd5tm | how does the "Hot Singles In Your Area' internet scam work? | Technology | explainlikeimfive | {
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"The advertiser uses a geoIP database to get your location and shows you some carefully picked pictures (that are the same everywhere, except possibly between countries with different distributions of skin colours). If you click it, it'll ask you a number of (very simple) questions specifically designed to waste a bit of time (yes, I want to meet strangers, that's why I clicked the ad) before either redirecting you to a different, similar site or asking for your credit card information. The idea is that, having wasted so much time already, some people will decide to just enter their damn CC info. At that point you might have you bank account emptied or just charged a dollar, either way it's unlikely there'll be anyone to meet in your area. Disclaimer: this is by no means a complete description of the possible consequences. Viruses can also happen. Edit: a word.",
"At best, you'd be brought to a site asking for your email address and other personal information, or some cheap paid porn site. At worst, you'd get some malware or something. (if you had nothing in your browser / operating system to block it)",
"Some are pure scams, leading to malware sites or just ways to get your email for spammers. Others mostly scams, leading to phone sex lines, porn sites, phone dating lines, and half-ass dating sites, all of which you have to pay for.",
"It isn't a scam per se it is just a deceptive advertising. They want you to sign up for something like a site that hosts cam girls and asks you to pay for shows, or perhaps a sleazy \"dating site\" that also serves advertisements for porn. The tag line is just a hook to get you to click, they aren't going to drain your bank account or something.",
"My 21 year old niece works for one of those companies. She basically just talks to people and strings them along, and she gets paid a dollar a message, so I have no idea how much they charge the idiots that communicate with her. She said a lot are just lonely guys wanting someone to talk to, but she certainly gets a lot of dick pics. She doesn't care, she just eggs them on so they keep writing and she'll keep making money. On the other hand, she has admitted she has sent some nudes of herself their way at times -- not including her head. So I guess there is a pay off of some sort. I just worry I may stumble upon one of her pics on the Internet someday and not know it's her. Thankfully she has no obvious identifying marks, like tattoos.",
"> As a relatively self-possessed 20 y/o girl I'm a 64 y/o computer nerd. We clearly have much in common.",
"Clicking will probably just redirect you to a website of dubious legitimacy. Giving them any of your contact info probably makes you a target for spam email and likely attempts to get you to give them money in one form or another (via subscription fees, posting fees, etc.) I'd assume they spend less time/energy/money targeting females as they are less likely to part with money for the prospect of getting laid.",
"They require you put your credit card details in to ***verify your age***. (Then steal from your credit card) The Internet Historian has an adventure seeking out the hot singles in his area in [this video]( URL_0 ), it’s 20 minutes long but I think worth the watch.",
"Great time to remind people to use 2 factor authentication on your accounts whenever possible.",
"I've never really understood why everyone assumes it's a scam. As a hot single in an area, there is one thing I like to know about a sexual partner: what is their credit card information?",
"They aren't usually scams. They want you to pay for some dating service that you may, but probably won't ever find someone on. Its unreasonably priced for pretty much nothing but its not fraud typically.",
"scam? Dude, I'm sexing horny milfs in my area all the time. Everyone thinks it's a scam, so nobody ever clicks on it... that's just more for me",
"If you ever really wanna try a scam and see where it goes, get a prepaid visa and leave a dollar on it. That's what I use for free trials.",
"How bout the fake headline with your town name in it claiming that a group of Asian college students (if they’re Asian it’s gotta be real right?) “are disrupting a 10 billion dollar industry.”",
"I am constantly impressed with how many hot single girls in my area are able to track me down and are so keen to meet me that they find a way to open a chat in whatever site I am on. It happens a lot... I guess I'm a catch",
"Basically just an interactive ad template that will usually end up linking you to already well known cam sex sites. Sometimes they use a long list of possible links to send you to, other times it's the same website, but 9/10 times it's not harmful to click on one, just pointless.",
"So, tangentially related to this, I just got for the first time today a trio of text messages from an unknown number. I am used to robo calls now, but this one was new. Got what I could only describe as an accidental text - someone speaking to me as if mid convo (saying something clumsily about being at the club), and immediately following was a second text continuing the chat, and then a flattering pic of a young woman's torso with shirt pulled up to reveal bra and cleavage, and a belly button ring. The phone number had an area code one digit off from my own, despite being from pretty far off geographically. Wanting to give this sender the benefit of the doubt but still protect myself, I popped into my Google Voice account and sent the number a reply like, \"I think you just sent to a wrong number\" I was then immediately sent the same three texts to my Voice messages. So, obviously bot. Or is it? I reply \"yeah, those were the ones\" and suddenly the texting becomes more conversational. She introduces herself as Jenny, and talks a bit more casually about being in town (a town close to me but not quite, it would be a 30 min drive) and visiting her sis before going back to Newark (place the phone number is from) and looking for fun. Second pic. At this point I'm solidly on the fence between bot soldiering through and person operating on a script. I have given my name (for the purposes of this I gave a feminized version of my middle name and pretended to be a girl) and they have repeated it back to me, and they have made an effort to be nearby. Script that captures name input? Geolocation abuse? Not out of the question. Then the twist: she's on her sister's phone and said sister needs to take off with it for a week! Oh no what's a girl with a dead phone but working computer to do? (I almost suggested Google Voice off the bat, but had a more naïve role to play.) I offered to wait til they charged their phone, no they want to chill now and won't be free later. How about computer chat? Before I say yes or no, they dump the link for their spam cam girl date site. Without even clicking the link, I say nah let's just be FB friends. If it's a bot, I will give it credit for recognizing lowercase fb and replying about the two sisters having a military dad who doesn't want them on social media. Could still have been a script reader. She said she was the sister now and that Jenny is waiting on the link from earlier. I stopped replying and researched the link. Very new sort of spam scam. I'm sure they just shotgun phones like the scam callers do, but man it was a very novel experience compared to just getting a phone call from a spoofed local number about my credit card, which hangs up if I dont answer the way they expect."
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8wdh69 | How the A* path finding technique works | Trying to wrap my head around it, and I feel like it's almost clicking but not quite. | Technology | explainlikeimfive | {
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"So you're trying to find a path to somewhere, and you can't see obstacles until you're right next to them. But you know where you are, and where the destination is. So what do you do? Well, the most obvious route is to move towards the destination right? So you do that, and do that, and do that, but now there's a wall, but a path goes off to the side into a tunnel, and then that turns, and turns, and turns, and turns. Sometimes you past by intersections and you take the turn that heads closest to your destination, more turns, and more turns, and then you hit a dead end. A* is trying to answer, what now? Essentially, it tries to guess which location among those it's already been to is the best one to return to to try searching further. Is it the starting point? Probably not, because you know at the beginning you were moving closer to the destination then your starting point, so it must be somewhere further. Is it at the last turn? No, because there was no where else to go at that point. Was it at the last intersection? Maybe? Was it at the first intersection? Maybe? How do you decide? Well you use a heuristic, essentially, you give all the places you've been points. Those points describe both how long you walked to get there, and how close that spot is to the destination. You then combine those two numbers together in some way, and you compare that number for all the locations. The lowest number is the next one you start searching from, and you continue. That's A*, essentially. The interesting things about that is that there isn't a rule for how you combine the two numbers for each location, maybe it's 2 * distance walked + distance to target to get a total. How you combine them determines the behavior of the path finding algorithm, and how effective it is at tackling individual mazes. That's A* as I understand it."
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8wdys8 | Why is gold used in electronics more than silver? | Technology | explainlikeimfive | {
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"Pure gold never rusts or corodes It's 100% non reactive. As a result it's more long lived in electronics.",
"Gold is much more resistant to corrosion than silver so whilst slightly more expensive to manufacture it is more practical."
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8wdzvw | How does a commercial “slushie machine” create such a perfect slurry of chewable ice? | Technology | explainlikeimfive | {
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"There is a metal cylinder that the flavored liquid is dumped into, and on the outside of the cylinder is a bath of freon or other supercold liquid. Inside the cylinder is a set of paddles that constantly rotate and scrape any ice crystals that form off the cylinder walls. So the instant a tiny ice crystal gets formed in the slush liquid, it gets scraped loose. That's how they do it. You can make the same stuff if you have an ice cream machine. Same process but just a different starting liquid."
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8wfakc | How do mouse, keyboard, etc drivers work? | Like, what do they control outside of basic functions and what takes priority during functions? | Technology | explainlikeimfive | {
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"You're a computer and you speak English, you have a mouse that speaks Spanish and a keyboard that speaks German. Drivers are the translators that tell you what they're saying and allow you to communicate back and forth. Anything that has to do with direct user interaction takes priority. ------------------------ Now to dig a bit deeper and little less ELI5. Operating systems have several layers in them that handle different functions and operations. In general you can consider two major sections, user space and kernel space. User space is where all of the user programs operate, and kernel space is where all of the system programs and functions operate (resource management, task scheduling, drivers, etc). Kernel space is a safe zone, and users cannot change or touch anything in kernel space on their own. There's a built in library of functions called system calls that allow users to access things and perform operations on resources controlled by the kernel space. For instance, lets say you want to read a file from your hard drive disk. Well, storage is a resource that's controlled by the operating system kernel (if users had direct access, that would be very bad. Imagine all the things that your tech illiterate grandpa could do to screw up his new fancy computer if he had unlimited access.) So lets say you open up Microsoft Word to read a file. What's actually happening is MS Word is executing in user space and then invoking a system call named read() on the file that is stored in the hard drive. When the system call is invoked, the CPU stops executing in user space and switches to kernel mode (this is called a trap). Now that it's in a protected mode where the user can't screw anything up, it pulls the data from the hard drive and sends it back to user space so that MS Word can read it. Now if you change something and want to save it, the same process happens with the write() system call. These system calls have a ton of security measures implemented and restrict what can and can't be done to system resources. Now that we know a little bit about kernel space, user space, and system calls, we can dive into drivers. When you press a button on your keyboard or move your mouse, this raises an alert on something called the interrupt request line. This signals to the CPU that there is some kind of external input that it needs to address. The CPU will acknowledge this alert and then trap to kernel space. It then talks to the interrupt controller to determine what's going on. Hardware devices like keyboards and mice convert analog signals into digital ones, the driver is used like the glue between the hardware layer and operating system. It translates the signals into something that the operating system can understand. When a hardware interrupt occurs and the CPU switches to kernel space to handle the interrupt, it's the device driver that provides the information for the CPU to process. Processes that are directly related to user interaction usually take precedence over all other CPU processes. That's why when a program freezes you can still move your mouse around and click on stuff. The CPU is trying to execute the program, but it's taking a while and it doesn't want to make the user feel like the whole system is frozen, so when the IRQ line is raised with a mouse interrupt, the CPU acknowledges it, puts the other process on hold, and executes the mouse process instead. This is a design decision by operating system programmers. When the mouse freezes, that usually means that the CPU is under extreme load or there's some other nasty condition like deadlock (Dining Philosophers problem) going on. Hopefully that's not too convoluted to understand. It's been a while since I've taken an operating systems course, so this is pretty much just what I can remember off the top of my head.",
"Hardware drivers control everything about a device. Anything the computer knows about the device comes from its driver. I don't know what you mean by \"what takes priority,\" so I can't provide an answer. Device-specific drivers take priority over the generic drivers bundled with the OS."
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8wjm3a | - Why do phones not require cooling vents but other small appliances do? | Technology | explainlikeimfive | {
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"Phones lack a cooling system because there's no room for that. It takes up way too much space for a pocket-size device. If that wasn't an issue, phones would've had vents. Besides, phones don't work as hard as other computers do. They are weaker, so they produce less heat. Still, they can get hot sometimes, especially during charging, and there is nothing we can do about it. Phones cool by radiating heat away and through conduction - passing heat into the surrounding air/skin.",
"Phones are very specifically engineered to be both low heat and to have passive cooling systems to dissipate that heat. It take a lot of engineering to do this properly, but it is necessary for a device that is meant to be carried and hand held. Other appliances _could_ have systems like this, but there is no real need for them. They can be large enough to have larger and more active cooling systems, which are less difficult to engineer and less costly to implement. Since there is no real benefit to making these other appliances smaller, they use the easier/cheaper cooling tech."
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8wk1e5 | Why do text files like .odt or .doc change its structure/layout when opening them with a different version of Word/Open Office? | Technology | explainlikeimfive | {
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"The file format tells the program opening it how to structure the data for you to see it. If the program you’re using doesn’t recognize the file format, then it has no idea how to lay everything out, so you’ll often come up with a page full of gibberish.",
"These documents are not text files. They are complex, object structured XML documents. Sure the MSWord program makes them look like text, but the underlying file format is very complex.",
"The content of the files generally contain the basic intentions of the display, but not necessarily the exact particulars. It's up to the configured preferences of the displaying application to combine that intent with the real display.",
"Those aren't text files. Those are proprietary file formats. If you open them with a different version of the program, it might have to convert them to their own format, resulting in some changes because it can't process certain commands. Another issue might be fonts. If your document is in a font that isn't loaded on another computer, the other computer will substitute it's own font, resulting in a change."
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8wl28g | Why do rockets have different stages? Why not just 1 big stage? | Technology | explainlikeimfive | {
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"For many rocket designs, the reduction in vehicle mass after discarding unused fuel tanks/engines after a point in the journey offers greater benefits than the cost of adding additional engines. Fuel tanks are fairly heavy, and rockets typically need less engine power once already in the upper atmosphere or orbit than they need to get off the ground. That extra weight does cost additional fuel to change the momentum of the rocket, so it is desireable to dump extra weight where possible. As an example, the space shuttle used a massive fuel talk attached to the orbiter, which was jettisoned before attaining orbit. The last version of the fuel tank weighed around 60,000 pounds empty, which is quite a lot compared to the space shuttle orbiter at about 160,000-240k pounds loaded.",
"Thrust to Mass A rocket needs fuel to propel a ship to space. All three of these have mass. Once fuel is burned in a given stage, it's empty weight. there's no need to carry that mass, so you dump it in stages. The trouble too then, for conventional rockets, that for more power, you more rockets, which requires more fuel, which all have more mass. The solution then is to start stage 1, use that fuel, dump that empty rocket, start stage 2 (rocket 2), use that fuel land then dump that empty rocket as well. source: Kerbal Space Program XD"
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8wo75e | how barcodes are made? | Technology | explainlikeimfive | {
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"If you specifically mean UPC/EAN barcodes that are on most products, it's pretty complicated. It's not just a font where each number (or letter) is swapped out for a symbol. It's hard for adults to understand, let alone a five year old. The [wikipedia article]( URL_0 ) is very thorough, but still pretty complicated. One of the features of these barcodes that you might not expect is that they have start, middle, and end symbols. That allows the barcode scanner to know whether or not the barcode is upside down (or sideways for newer 2d scanners). Another feature is that there is a \"check digit.\" The check digit is the last digit, and it is calculated from the other numbers in the barcode. There's a weird algorithm for calculating this last digit, and it is designed to catch common data entry errors. In the most common UPC codes (UPC-A), 100% of single digit errors can be caught with the check digit, and 89% of transposition errors are caught as well."
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8wo7o2 | Would I have a similar experience to having a bigger TV, if I sat closer to a smaller TV? | I'm really curious about screen size/viewing distance ratios. I really like to sit towards the front of the movie theater because it feels like the screen is bigger and more immersive. However, if I were watching a movie on my phone up close, wouldn't it look bigger? Would that be a superior experience (assuming I am using high quality headphones)? | Technology | explainlikeimfive | {
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"No because you would have to move the phone too close to your eyes for that to be comfortable. Also, you have to hold the phone or buy/design something to hold the phone less than a few inches from your face. Might as well get a VR headset and watch the movie that way."
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8wowev | Why is desalination not yet a cost effective solution for the world's clean water demands? | Technology | explainlikeimfive | {
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"There are only a few ways to desalinate water. One way is to boil and condense the water, a process called distillation. The problem with this is that it takes a relatively enormous amount of energy to boil water so it isn't practical. If we had limitless energy available to us then it would definitely be on the table, but we can't just pull huge quantities of heat out of nowhere. The other way is to force the salty water through special filters which are fine enough to filter out the molecules of salt while letting the water molecules through. This also requires a fairly large amount of energy (pushing the water through requires a lot of pressure) and it also has the added trouble of fouling up the filters which need to be cleaned regularly. Overall the process of removing salt from water is very difficult and usually not cost effective, compared to the natural water cycle where the enormous fusion generator evaporates water over hundreds of thousands of miles for free.",
"Producing water with evaporation requires too much energy, it is used only in places where you have some free heat, like in a ship due to the Diesel engine. Reverse osmosis used to consume a lot of energy, but way less than evaporation / boiling. However new materials make it way less energy consuming compared to several years ago, in Israel it is now used to provide part of the water supply in the country. So to answer your ELI5, I would say, desanilisation is in the process of becoming a cost effective solution. URL_0",
"Because water is **extremely cheap**. The price people are willing to pay for water is almost nothing, so an energy intensive process like desalination can't compete with the vast sources of available fresh water. Maybe on a cruise ship or submarine it's cheaper, but everywhere else just using existing fresh water sources is cheaper.",
"In addition to what everyone else has said, there is the complication of what to do with the leftover extra concentrated salt water. You can't just go dumping that anywhere, life is very sensitive to salt levels on land and in sea.",
"There is another element that connects some of the other items together. If you take an amount of salt, and mix it with water, it ends up in a lower entropy state. To convert it back to separate salt and water there's a minimum amount of energy you have to have the two separated. There's no way around it. There's all sorts of nifty tricks to try to get as close to perfect as possible, but no matter what, it takes a fair amount of energy. A way to view this is if I take a bag of blue marbles, and a bag of red marbles, and mix them up, then want them sorted again, I have to spend some kind of energy to get it sorted out. [See this article]( URL_0 ) for an another way of explaining the same problem. > it will always take 1 kWh or more of energy to desalinate a cubic meter of seawater.",
"The simplest ELI5 is that it's very energy intensive compared to using fresh water sources.",
"Follow up question from the explanations and my limited understanding of energy production. If most ways of making energy require boiling water, what is the downside of using salt water in the process of creating energy and desalinating it at the same time? At least assuming that the power plant is near the ocean."
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8wpaet | Why did it take till now to develop phone chargers that fit both ways? Is there some special technology in making it fit both ways, or did just no one think of it till now? | Technology | explainlikeimfive | {
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"It's really a case of no-one having bothered to make one until recently. There are some technical hangups like having to duplicate certain wires on both sides of the connector but that's more a design nuisance than a real technical problem. USB has been notorious for issues with plugging it in wrong-side up since it's earliest days but the difficulty of creating and getting everyone to agree to use a standardized connector is such that no one bothered to try to fix it. Apple may not have come up with the idea of a reversible connector but they made the idea of one popular with \"Lightning\" the standard connector for the iPhone et all. Apple has the philosophy of using proprietary connectors whenever they can get away with it, so they had the upside of being able to develop lightning without needing to pass it by any standards bodies first. In other words less red tape. USB-C was released partly as an answer to it, and partly to meet European law that mandates that all cellphones use the same charging connector. A law that Apple lobbied strongly against.",
"For a long time, they designed connectors purposely asymmetric so that people COULDN'T plug them in wrong. Look at DVI or VGA or old style parallel port. (The connections are parallelograms (EDIT: Trapezoids... I didn't pass 5 year old test of \"shapes in holes\". apparently) , not squares.) It simply took people a while to figure out that \"hey, we can design smaller connections now and they're no need to have them be \"keyed\" like there was in the past.\" Basically, back in the day the state of technology dictated that we needed connectors that only plug in one way. And it takes a while for something so ingrained like that to go away. Also asymmetric connectors \"hold on\" better.",
"They had this ages ago. The connector was round, with a pin in the middle. This charging standard was great, but it only did charging. The whole USB thing came up to do data and charging at the same time.",
"To add on: not that long ago, connecting peripherals and hardware to computers was a crapshoot of different connectors and wires, and everything needed to be keyed correctly in their connections to work properly. As such, connectors were asymmetrical and differently sized to prevent damage if they were put in the wrong spot, which still happened frequently. When USB came out, it set a standard for connections, and allowed flexibility where there hadn't been much before. But, manufacturers know that if you make something idiot-proof, someone somewhere will build a better idiot, and to minimize the possibility of damage they kept them keyed a certain way. Or nobody could be bothered. One of those two.",
"Nobody wanted to break standards. The microUSB connector was standardized for phone chargers early on, when USB did not have a reversible connector. And is the inconvenience of using a one-way connector really that great. Also, Apple's lightning connector has been on the market for a while, and is reversible.",
"Think of a USB connector as a digital freeway. You have two north-bound lanes and two south-bound lanes. If you were to \"disconnect\" the freeway and reconnect it, as long as the north-bound lanes match up with the north-bound lanes, and south-bound lanes also match with south-bound lanes, then the freeway works as expected. If, after disconnecting the freeway, you flip one part of the freeway before reconnecting, north-bound lanes match up with south-bound lanes and everything becomes a mess. To solve this problem, and allow all freeways to connect in any configuration, you need a special interchange. This special interchange is an add-on expense which manufacturers decided to skip when USB first came out.",
"I'm not sure the USB standards group [entirely knew what they were doing]( URL_0 ). USB-3.0 came out around the time when phones were switching to Micro-USB B. This was also before phones started to get decent capacities for internal storage. A few years passed, and phones needed faster data transfer, so USB-3.1 was developed. But the USB-3.x high speed connectors were weird and ungainly in the interests of backward compatibility. So manufacturers designed a new connector. And they saw that they could make the connector reversible, so they did.",
"\"Phone chargers\"? Are you talking about USB connectors? And what about older chargers with round connectors that fit in more than just two ways? Or Apple's Lightning connector, that has been used for 6 years or something?",
"If you want to take a step back, phone chargers 15 or so years ago before the dawn of smart phones were proprietary, and may were actually reversible. Some were as simple as the old round plug into socket. As phones became more prevalent and battery tech better where the need to exchange data where you would want to connect it to your pc, and \"hey, there is some voltage on here that we can use to send an effective charge the thing\" happened, they were somewhat contained by the standards of the time. Hell even then it wasn't uncommon for you to have a dock that had AC power run separately, and then a USB or serial connection (early gen palm pilots and the like). Yes, you would plug your device into that dock, which was foolproof, but you weren't making and disconnecting the connections to your pc\\the wall a few times a day. USB, while a standard way to connect stuff, still wasn't meant to be constantly plugged in and unplugged 20 times a day in its original design. So in short, it didn't matter it took you 2 (ok, 3 tries) to get it to plug in right most of the time. So when it DID become common for you to do that, you still had to maintain backwards compatibility with a ton of devices. Which meant that if you wanted to keep one end the same (the big end of the USB cable) that could plug into something you knew almost everyone had, the other end had to be able to handle the \"ok, i'm plugged in backwards, or i don't care which way i'm plugged in, part\". unfortunately that end was on the device you were most concerned with when it came to size and efficiency of the connection. Which took some time for tech to get to a point where your phone is able to deal with that, the cables can deal with it, and it all can be done without compromising other capabilities of your device and at a good price point. Real ELI5: USB wasn't designed with that in mind, because you weren't constantly plugging and unplugging stuff originally. When it became common, it was too widely implemented to do it on on the easier side to do it, so you had to wait for tech to catch up on the other, harder, side to do it on.",
"In the old days companies didn’t care about compatibility. Each company had its own proprietary charger, some even changing shape from one mode to the other. The regulation of phone chargers to a common type paved the way to stop this carnage. The USB connector/standard was a natural choice. It was initially developed to allow real-time voice-over-data communications with “phantom” power delivery over the same cable - an idea that has been around since a very long time in audio systems. It provides enough power to power and charge many devices, unlike older standards that did not support this feature (100 mA up to 500 mA charging current with 5V DC voltage, which is suitable for directly charging many batter types without the need to extra circuits). The catch was that USB connectors were polarized; they cannot be flipped. The reason back then was that DC connectors cannot be flipped or they will damage the circuits - it would literally fry them. Nowadays however, there are power circuits that could be added to automatically correct a flipped power connection without damaging the circuits. In the old days it was not much of a requirement really because the advent of the USB was a big advancement and revolutionary its own right. But now, after we have had enough experience with its advantages and limitations, it’s quite evolutionary to require that connection to be unpolarized."
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8wr3at | How do power/charging strips get enough power to charge multiple devices? | You know those power strips that charge a whole bunch of stuff at once? How do those get enough power to charge multiple electronics through ONE outlet? | Technology | explainlikeimfive | {
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"Electrical power = voltage * current. Power outlet, US: 120 v * 10 amps = 1200 watts. Typical phone charger 5 volts * 1 amp = 5 watts. Thus, an outlet has enough power for 240 phones / similar devices. TV's, stereos, computers: 50 - 100 watts. Refrigerators 200 - 400 watts. Ovens, space heaters: 2000 watts (require 20-amp circuits)."
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8wry29 | Why does power saving use grayscale? | Companies such as Samsung use grayscale but doesn't that use more power than RGB? I thought so as gray is made up of all three elements but blue is just using the blue led? Why is this? | Technology | explainlikeimfive | {
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"LCD screens have white backlights that are filtered through basically tiny colored foils. If you want red. You shut the blue and the green subpixels. And since the whole light comes from the backlighting, you basically shut out 2/3 of the generated light. With greyscale, all subpixels are „opened“ equally and you get the most of the backlight, alowing to dim it and save power."
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8wtynu | How did people reset their clocks when the power went out, 50 years ago? | Technology | explainlikeimfive | {
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"Well son, back in my day we had these time pieces we wore on our arms and they called them watches. If you didn't have one or your battery dies, you could just ask the fella next to you: \"Hey bud, you got the time?\" And he would be happy to oblige and tell you."
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8wua37 | How do stock photo companies such as Shutterstock make money? | Technology | explainlikeimfive | {
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"They put the watermark on to prevent people from using it but being able to see it. They sell you the picture without a watermark so you an put it in your brochure or whatever you need it for. Regardless of how big a company is, spending an hour shopping around for a picture is easier and cheaper than buying camera equipment and sending a photographer and actors to make the picture that shutterstock already has.",
"Local companies are always buying stock images for advertising purposes. Advertising companies buy them too. I work for a small local news company and we use stock images for video things all the time. We have a subscription with Getty Images. For us it’s usually things like pictures of heroine “tools” bc of a news story we’re promoting on drug use. Things like that.",
"> just don't understand how paying people to take photos and then putting them online with a watermark is profitable For starters, like everyone else said, the actually money comes from selling the rights to use copies of the image without watermarks. Lots of professionals need stock images & are willing to pay for the pictures. The threat of getting sued for using them without permission is too much risk to justify spending a few hundred bucks on rights to a picture & that's still less than taking the pictures yourself. As for \"paying people to take photos\", a lot of the photographers don't work for the stock image house - they're just taking a bunch of pictures & uploading them, hoping to get a percentage of the payments *when somebody actually uses the pictures*. Under this model, the stock image company doesn't really have a lot of investment - they just have servers set up to store pictures & take a cut of every transaction. Being a middleman has always been profitable - especially when you don't have to tie up capital in holding inventory."
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8wv6gw | Why can the TV get signal more easily and more reliably while internet can hardly upload/download stuff in comparison? | Technology | explainlikeimfive | {
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"> Why is TV so much powerful on getting data compared to the internet? Television is one-way while the internet is communication in both directions. It is like the difference between using a loudspeaker to communicate to 100 people vs. holding 100 separate conversations simultaneously. If you are relaying the first instance you only need to pass on one string of words, but if you are trying to relay the second you need 100 different streams. Plus they can respond so each person actually needs two streams, one down and one up. This means broadcast television is one signal and internet can be millions.",
"HD TV is a pretty recent thing. Lesser resolutions were common up until this decade, especially with older TV setups. TV is broadcast, and the format of the arriving data is known, so your TV doesn't really have to calculate anything. It's just a stream that your TV displays. Internet is a conversation from point to point, and there are middlemen, and the content format varies depending on what you're doing, and the signal might need to be routed around traffic problems, and you get the picture. The flexibility of the internet requires a more complicated signal along with computers to decipher it. Imagine the kind of massive water cannon you'd need to put 1 gallon of water on every house in your town. Massive but simple. Now imagine the difficulty in delivering exactly 1 gallon of water to 100 houses in your town while avoiding all the others. Much more complicated, especially when which houses want water changes by the second."
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8wwdde | How do viruses propagate between computers? | I understand that computer viruses do their harmful work somehow and then attach to other programs and executes when the target program executes. But how does the attaching stage work? EDIT: I don't mean how viruses spread. I mean how does the virus attach itself to a program so it runs while the target program is running. | Technology | explainlikeimfive | {
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"As a concrete example, a PDF is an executed file. There's actual code in a PDF that needs to be run, unlike a text file where it's simply read and displayed. This means that when you open the PDF, the attached code could very well run, and if that code is malicious, then there goes your computer. Additionally things like DVDs and some flash drives come equipped with a file called autorun.exe which does exactly what it sounds like: it executes automatically when the computer spins up the disk or connects to the flash drive. If that code is malicious, there goes your computer. Beyond that, the virus might attach itself (and the autorun) to any flash drive you connect, perpetuating the cycle to the next round of computers."
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8wwuwr | How does the Buffer Overflow exploit work? | I know what a buffer is and what overflow (as in integer overflow) typically is, but how can overflowing a buffer ever compromise a system? | Technology | explainlikeimfive | {
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"I need 16 pieces of memory please! < stuff that isn't yours > _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ < stuff that isn't yours > Please write the following message in my memory: puppiesarecute!!KILLEVERYTHING < stuff that isn't yours > p u p p i e s a r e c u t e ! ! K I L L E V E R Y T H I N G isn't yours > Now, if the computer didn't check to make sure my message was capped at 16, then there's now an instruction to kill everything hidden in the memory. This could be very bad if I tricked the computer into reading from that location."
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8wxw24 | how do dual SIM phones work | Technology | explainlikeimfive | {
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"A [dual SIM]( URL_1 ) phone can hold / use 2 [SIM cards]( URL_0 ). The SIM card holds an identifying (hardware) number that identifies the phone, so you can set up a subscription and associate the SIM number with a phone number. So dual SIM phones can answer/handle two separate phone numbers. These can be on the same provider (Verizon for example) or on different providers (one Verizon one AT & T). Popular with business persons; they can have a single phone device, but a personal number and an official business number on it."
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8x0z30 | Why is it fairly easy for large animating companies to create perfectly photo-realistic terrain and animals, but not humans? What really is the difference? | Technology | explainlikeimfive | {
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"I believe this has to do with an effect known as \"the uncanny valley\". See, humans aren't particulsrly more difficult than animals to animate, but we as humans notice slight errors in animated humans fsr better than other things. Thus, what you call a photorealistic animal likely has some distinct differences from an actual film of that animal, but our brain is not keyed to detect that. However, if an animated human has a similar amount of difference, our brain picks up on it much, much easier and we think it looks \"off\"",
"I think it is mostly a problem with the audience not the animation itself. An astonishingly big part of the human brain is tasked with looking at, recognizing and parsing information from human faces. We are evolutionary optimized fro that sort of thing. If grass looks vaguely like grass that is good enough in most cases. A human face however is something we pay a lot more attention to. We can recognize something as a face if it is just hinted at with two dots and a line :) or greatly stylized as a smiley: 😀 But we are so focused on looking at faces for information vital to our survival that we can recognize that something is not quite right with a face, even if it is almost photorealistic. Even if we can't put it into words we know that something is wrong with a face and parts of us that have evolved over a really long time will cry out in the back of our minds urging us to that something is not right here. This is when you get the uncanny valley effect. Close enough to the real thing to be almost mistaken for it but still not quite good enough to pass as it. So making an almost photorealistic background is easy enough. With humans you either make them purposefully not quite realistic or you have to put a ton of extra effort into it.",
"It's about how much attention we pay to things. If something is on the table, looks vaguely like a vase, and has flowers in it, then I will glance at it, mark it as a vase in my mind, then dismiss it from my thoughts as unimportant. Human faces are different. We look at them in detail and watch the tiny movements as we try to gauge the person's current mood. Because we look in such great detail, we will notice any tiny little thing that seems \"off\" with the vision, even though we couldn't possibly explain in detail exactly what it was that doesn't seem quite right.",
"I'm not entirely sure because I'm not an animator, but I would think complexity has a good bit to do with it. Like take grass, it's really just a some tapered triangles with a clothlike texture and boom grass is done. But humans are so much more complex than that. We have pores, hair everywhere, a whole bunch of muscles that move slightly, imperfections ect. On top of that, humans are really good at recognizing faces. That's why we see faces in everyday objects. So I'd imagine the brain is particularly good at figuring out what a real face is.",
"The uncanny valley is definitely a factor in this, but take it from someone who works in the animation industry—the real answer is money. 2D BGs are paintings and generally have minimal interaction with the characters moving on top of them. This allows them to mostly be still images, which means that BG artist can spend the time to paint them since their complicated artwork won’t have to be animated. It’s why in old cartoons like Scooby Doo you could always tell that one trash can that was going to be interacted with, because it was drawn more simply than the painted ones around it. Animating even simple humans is hard as it is—walk cycles are incredibly complex, and the more realistic the human the more time and effort it takes to animate a second of your content. Why pay all the extra money to do that when you can design a character more simplistically and it won’t be a detriment to your audiences connection to them? TL;DR: Simple designs don’t have to worry about the uncanny valley, but serve a dual purpose because they are also cheaper to animate.",
"One of the major reasons is just artistic choice. If you really want photo-realistic humans then you can just hire human actors, especially with modern green screen technology. You only *need* animation when you want something other than photo-realistic humans. Animators actually can create strikingly lifelike human animations, especially with hybrid technologies like motion capture, high resolution 3D scans, and now machine-learning deepfake technology. If Disney ever tries to put Princess Leia back into another Star Wars film, expect her to look perfect.",
"There are many good answers, but few satisfying ones. The way the brain interprets what we see turned out to be far more complex than anyone had guessed. Even scientists who had spent years on the problem completely underestimated how difficult it was. The vision problem is now considered a part of what's called Moravec's paradox: \"it is comparatively easy to make computers exhibit adult level performance on intelligence tests or playing checkers, and difficult or impossible to give them the skills of a one-year-old when it comes to perception and mobility\".",
"If you stare at the fine details of a 'perfectly photo-realistic terrain' in a video, you'll be able to spot things that don't quite seem right. Lighting, colors, maybe a shape isn't quite right or a texture isn't quite right or those tree branches look too weirdly uniform, etc. The human brain however, is innately trained to recognize human faces. Why? It's a survival instinct. Being able to distinguish between people means being able to distinguish between someone you can trust, versus someone that might kill you and steal all your stuff. As a result, we'll be a lot quicker to notice things that are just OFF with people.",
"My description relies heavily on the understanding of evolution: I full heartedly believe that as human beings we are highly Advanced biological chemical computers with very old software... Our software is what got us to survive ridiculous situations even though we aren't the strongest, fastest, nor toughest creatures, we are the smartest and that's why we survive. Particularly when it comes to recognizing humans, the most dangerous thing for humans is other humans. This is very true today as it was when we were cavemen. It was much more important back in the days before you had police officers, back when there was cavemen rolling about, if you approached the wrong human you might die, so we are the survivors / descendants of all the human beings that made the right choice in not approaching a dangerous human even though he looked very similar to our uncle or Aunt or father or brother's friend, and it's very difficult to tell who is who especially from far away. Our minds are incredibly adept at Discerning the differences in Walking patterns, facial features, speaking patterns, body language, Etc. Now when you attempts to determine the difference between Landscapes or animals, it really doesn't matter if said landscape or animal is exactly Jimmy the buffalo or Massachusetts the valley, all that really matters is is it safe or not so if it's a cliff it's not safe but it doesn't matter what cliff. If it's a venomous snake it doesn't matter what kind it's not safe. If it's a human that you don't recognize it's probably unsafe."
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8x15zq | How do 7.1 surround system headsets work? | Technology | explainlikeimfive | {
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"The most important factor for how you determine what direction a sounds comes from is the time delay between the sound hitting your ears. A sound that was generated directly in front of or behind you would hit both ears at the same time, whereas a sound that was generated directly to your left would hit your left ear first, then a fraction of a millisecond later, your right. Furthermore, your brain uses sound volume to determine how far away from you a sound was generated, although this is a lot less precise. Headsets like these can slightly delay the sound to one ear or the other, making it sound like it's coming from behind you or to one side or whatever they decide. There are other tricks that get into how sounds at different frequencies can be made quieter or louder or delayed slightly to create different audio effects, but those are outside of my ability to explain simply."
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8x1xtq | I understand the basic of waterless urinal. But without water flushing and cleaning the wall, won't that be dirty and stained? However, most of waterless urinals I have seen so far no stain at all. How could that be? | Technology | explainlikeimfive | {
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"**Here is how it works:** 1. Urine flows into the drain insert of the EcoTrap®. 2. Inside of the EcoTrap® the urine moves through a floating layer of proprietary immiscible BlueSeal® liquid, which creates a barrier, preventing sewer gases and urine odors from entering the restroom area. 3. The urine below the BlueSeal® barrier overspills into the central tube and travels down into the drain line. 4. Approximately 1500 sanitary uses are possible with just 3 ounces of BlueSeal®. When the BlueSeal® liquid is gone, it is simply replenished. This only takes about 20 seconds to perform and the EcoTrap® is not touched. 5. Urine sediments are retained within the EcoTrap®. Replacement is easy and need only be done 2 to 4 times per year depending on traffic to the urinal. As tool called the X-Traptor® must be used to remove the EcoTrap®. The use of the special tool helps to minimize vandalism. The entire process of replacement only takes 3 to 4 minutes.",
"The surface of the urinals is coated with a material which uses the lotus leaf effect, thus the liquid (and with it, the stuff that leaves stains when dried) does not attach to the surface as much as usual with porcelain or other surfaces. Less residual liquid, less stains. The lotus leaf effect basically works like this: imagine you do not have a smooth surface, but a surface with lots of tiny tiny little hills and valleys. The liquid drops (pee) are so large in comparison that they only touch the top of the tiny hills, so that the total area of the drop making contact with the surface is minimized - and because of this, the drop does not stick, but moves on. Imagine a beach ball moving over lots of combs - at any given time, the beach ball touches only a few tips of comb spikes, much less area than it would touch on a flat surface.",
"I uses to work at a hospital with watetless urinals and the restroom always smelled like piss."
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8x2fr0 | What is the difference between LCD and LED displays? | Just got a new LED and the picture looks clearer than an LCD. What's the difference? | Technology | explainlikeimfive | {
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"LCD - Liquid Crystal Display LED - Light Emitting Diode Despite having a different acronym, an LED TV is just a specific type of LCDTV. ... Older LCD TVs used cold cathode fluorescent lamps (CCFLs) to provide backlighting, whereas LED TV's used an array of smaller, more efficient light emitting diodes (LEDs) to illuminate the screen. LED runs \"colder\", longer, and brighter. TV's are thinner.",
"Others have said the difference with the backlight, but i thought i'd tell you about the LCD part. Essentially these TV's show white light, (cfl or led) and they use filters to limit what part of the white light can pass. Since white light is the total of all coloured light, you can block any colours you don't want. Each pixel is made of subpixels. Subpixels are filters, of red, green, and blue. ( Think of those old school [3D glasses]( URL_0 ). ) Using combinations of these three, can create orange brown, purple, and everything in between. What the LCD part does, is allow how much light will pass through these filters. If you think of [calculators]( URL_1 ), the display here is an LCD. The liquid crystal, can block light when electricity is passed through it. LC's in tv's and monitors have 256 different shades, or levels of opacity, for 8Bit displays, and 1024 shades for 10Bit displays. They can be full transparent, full opaque, and 256, or 1024 shades in between. Not simply on or off. Each subpixel has it's own LC shade. Older LCD TV's used CFL's, and the newer ones use LED's. LED's allow for a more uniform, and local light source for each subpixel, so the \"cleanness\" your noticing is due to that. The new OLED, TV's, don't use LC's for filters, instead using coloured LED's as subpixels."
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8x3dub | what is the difference between Linux and UNIX? | All the definitions of them are really stupidly complicated, I just want to know what the difference is. They have similar commands and file structures no? Are they not pretty much the same thing? | Technology | explainlikeimfive | {
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"Almost, but not quite. It's the difference between milk and cream. Very similar, but I don't recommend using cream on your cereal. **TLDR:** Unix is not free, cannot be modified, is very powerful, but can only run on specific hardware under specific circumstances. Linux is free, anyone can muck around with it, is extremely flexible and can run on anything with a processor, but isn't quite as popular in large scale operations (not that Linux is rapidly becoming a lot more popular in high-end server farms). Both have similar structures and commands since Linux was created to be like unix in as many things as possible, only free and able to run on home computers. **NOT TLDR:** Unix is closed-source, meaning in order to use it you need to pay a fee to licence it. It is less flexible than Linux and will not run on as many differenc CPU architectures and machinery that Linux can run on. Unix can support a more limited number of different file system structures while Linux is more forgiving and supports a number more of these systems. Linux is open source, free for anyone to use and modify, is more flexible, and is easier to install and set up pretty much anywhere on anything. It is based on Unix and thus is very similar in make and manner. Linux is more easily coupled with a GUI, while Unix is mainly supported by a command line. Because Linux can be modified and adapted by anyone there are more versions and distributions serving all niches. Unix is more robust and is specifically centered around high-end production cycles. You're more likely to find Unix on server mainframes, large datafarms, and high-performance systems. Linux is more popular on small-to-mid range use, personal computing, powering millions of gadgets, and specialized servers. However Linux has been catching up and is now a very popular OS in server-farms in its own right.",
"The short and uncomplicated answer is that Unix is trademarked and only OSs that have paid for and passed certifications can be called a Unix OS. Linux is a Unix-like OS. In many important aspects it behaves like a proper Unix but is not certified as one.",
"In simplistic form: UNIX was what was running at all the schools and large companies. The creator of Linux (Linus Torvald I believe?)created it to work as a “home version” of UNIX, so he could learn outside of the classroom.",
"Linux is basically a Unix clone. It was written by Linus Torvalds. Now, here are some differences. Linux is open source, meaning anyone can grab the source code and make their own variation of it. This has been done hundreds of times. Some popular Linux variations, or “flavors” as they’re often called include Ubuntu, Fedora, Redhat, Linux Mint, Kubuntu, and many more. Unix is not open source. Linux primarily uses a GUI (graphical user interface) with optional command line. Unix is primarily command line. Linux is portable, meaning it can be installed on basically anything. Computers, flash drives, phones (Android is highly Linux based), I have even seen people running it on Playstations. You can’t do this with Unix. Linux is very bare-bones. This means it doesn’t require much as far as hardware goes. This makes it a great choice if you have an old outdated PC that you want to bring back to life. Unix on the other hand, is pretty hardware dependent and usually used on complex server systems and top of the line computers. Linux has more file system support. It supports xfs, ramfs, nfs, ext1, ext2, ext3, ext4, tar, any many many more. Unix only supports zfs, js, hfx, gps, xfs, and vxfs. Linux is developed by a community. Anyone can take a part in it. Unix is developed solely by AT & T, and has been that way since it was created in 1969. Fun fact: Mac OS is a certified UNIX based operating system, if you didn’t know. Windows is based on OS/2, which was the successor to DOS."
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8x3fkn | Why can my phone with a 4 watt SoC play back 1440p video without even getting warm to the touch while my laptop with a much more powerful GPU has to ramp up it's fans and make tons of heat to accomplish the same task. | Technology | explainlikeimfive | {
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"Ah yes, Google’s and Apple’s VP9 beef. Blame Apple and/or Google. Whichever you think is guilty. Gather around kids, let me tell you a story. I’ll go off the assumption you are referring to a YouTube video here. And I am assuming you are using Chrome, not Safari, as Safari cannot play 1440p YouTube video (we will get into why later). The reason is video codecs. The issue with video is that video files normally are massive. If we use 1 byte for red green, and blue for each pixel of a 1080p video, then each frame of the video (and there are probably 30 frames in a second) takes up 6 megabytes (3\\*1920*1080). A single second at 30 frames per second would take up 186 megabytes as a result. We don’t have the bandwidth nor the storage to handle this. So what do we do? We do a little thing called compression. Compression just uses a bunch of neat tricks to make a video file smaller. For example, if a part of the screen is all the same color, instead of listing the color multiple times, we just list the color once and say “all of these are the same color). Now for some history. There are multiple algorithms for video compression out and about. The most common these days is called h.264, aka the Advanced Video Coding, or AVC. It was established in the late 90s and early 00s. The Moving Picture Experts Group (MPEG) was an organization that was formed in the early 90s to produce such algorithms and this was their latest iteration. The issue with MPEG was that they included many different companies who each contributed their patents and findings but refused to give them for free, they started getting greedy. Everyone wants royalties, and a company is formed with the sole purpose of getting everyone to agree to a single set of terms of use. Nonetheless, the algorithm was released with pretty liberal terms of use. The year is 2006. Google recently purchased YouTube and MPEG had hints going around of a new video codec algorithm to be released. Google decided to take a different approach, they saw that MPEG was gonna have more issues with parents as each new iteration of their algorithm brought in more knowledge and thus more patents. Instead Google teamed up with a little company called On2 technologies, who designed several codecs to produce the VP8 codec, released in 2008. Eventually google would buy On2 and release the codec for free for anyone to use. A few years pass, Google is proven right. The new codec MPEG is working on, the High Efficiency Video Codec (HEVC, also called h.265) is turning out to be good but a patent hell (the end consumer doesn’t notice this but companies making operating systems and hardware do). Google iterates on VP8 to produce VP9, a pretty good codec, lagging slightly behind HEVC. But it isn’t a patent he’ll and google says it is good enough. YouTube has become the giant it is today and Google begins to make YouTube use their VP9 codec. One of the key things one must understand as well is a little thing called a hardware decoder. In computing, there is a principle known as abstractness. One can design a chip that can do one specific thing very very well but can only do that thing, or one can design a chip that can do everything, but slowly and more inefficient in comparison. And this is on a spectrum, CPUs for example do everything but not as well, GPUs are more in the middle, can’t do as much as a CPU but they are very good at doing calculations related to graphics. These newer generations of codecs are very computation expensive to use, decoding a video takes a lot of CPU power. So the solution is to design specific parts of the GPU for the sole purpose of decoding video in popular algorithm formats. These are known as hardware decoders, they remove the strain off the CPU to decode, saving both battery and computational power. This is very important in phones, as they don’t often even have the computational power to decode a video with the speed necessary to watch it. So phone processors were the first to implement hardware decoders. But there are still benefits to hardware decoders on normal computers and especially laptops, who have limited batteries that shouldn’t be wasted by ramping the processor up whenever a video is playing. So, recently Intel and the other chip companies (AMD and NVIDIA) have all implemented. AVC was the first hardware decoder to be implemented onto many platforms. Then HEVC and VP9 were also added. With many modern devices now supporting VP9 hardware decoding, Google now is trying to switch to ditching AVC and using VP9 only. At this point, most browsers and operating systems have all implemented support for VP9 hardware decoders, except Apple. Despite their hardware (including the iPhone) having hardware decoders for VP9, Apple has refused to implement the software to allow it to be used by apps and browsers. A codec unsupported by a browser will not play in the browser at all, with or without a hardware decoder. Safari does not support VP9 decoding so YouTube must feed them AVC instead. Chrome on the other hand is Google’s ballpark and they can implement support for VP9 on Mac easily, and they did. But without support from the operating system to give Chrome access to the VP9 hardware decoder, Chrome cannot use it. Google has recently started putting pressure on Apple by refusing to support AVC content for 1440p and 4K videos. Apple as always is silent on the matter and has refused to comment at all, but as a slap to Google, they recently implemented support for HEVC decoding on Mac, but not VP9. So the answer to your question is this. Phones use hardware decoders to make decoding video, the computation intensive task of processing video, more efficient in terms of battery and computation. Computers have this ability as well nowadays. Due to Apple refusing to implement support for a hardware decoder THAT IS FOUND IN THE DEVICES, Chrome has to rely on the CPU to decode VP9 video which YouTube sends to them, making things hot and sweaty. TL;DR: Google made a new video format. The hardware inside Macs support making processing said video format clean and easy. Google has forced Apple to use this new video format. Apple has refused to implement support for this hardware. Your Mac has to fall back on using the CPU instead of more efficient hardware it already contains. PS: Google began working on VP9’s successor, called VP10. A few years ago. After seeing the collapse of MPEG, many companies and organizations wanted to help Google out. Google then decided to allow their contributions if and only if they released the rights and patents to it and founded the Alliance for Open Media and renamed their codec AV1. Supposedly this codec is slated to release very very soon and should topple HEVC. All major hardware companies have pledged to implement hardware support of AV1 ASAP. Apple has also apparently joined this alliance.",
"Probably because your phone has hardware that can decode the video, while your laptop needs to do it via software."
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8x3hom | With all the wireless technologies we use (Wi-fi, satellites, cellphone towers etc), isn't it a concern that it might get "congested" and cause the tech to fail? | Technology | explainlikeimfive | {
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"In the US there is an organization called the \"FCC\" or the Federal Communications Commission which regulates the frequencies which wireless devices can employ in order to prevent such interference and failures. Other countries have similar bodies.",
"It does get congested. If you live in apartment with lots of people with their own networks there can be a lot of interference on certain channels. Usually, wifi devices will just pick up your router's signal but if the unit next to you uses the exact same channel you could run into issues.",
"There is a concern which is why most of the radio spectrum is regulated and licensed out. If you have an application that needs to work then you have to buy a chunk of the spectrum for the area and then you get exclusive rights to it For stuff like WiFi and Bluetooth which are in the unlicensed 2.4 GHz band, we regularly encounter congestion issues especially if you have several WiFi networks in range of each other. To help deal with this, the power of devices operating in the unlicensed band is limited. Bluetooth and WiFi transmitters are restricted to 1 W of power, this reduces the range at which they will cause interference and keeps your network from shouting over one from across town.",
"Wireless technologies are allocated frequency bands and within those bands, there are typically multiple channels available. As an example, WiFi has 2.4Ghz and 5Ghz bands. The 2.4G band has 11 channels. 5G has many more. Radio signals have a limited range and so the bands and channels can be re-used, given some geographical separation. Most devices are able these days to change channels on their own to avoid congestion. But yes, given enough devices in a small geographical area, congestion can be a significant problem."
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8x5i0k | Why do games have “press any button to continue” before they start? | I mean specifically before the main menu of a game even loads. Such as fifa, rocket league, battlefield, etc... | Technology | explainlikeimfive | {
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"Its an old leftover requirement. Basically it sets which controller or input method the game will pay attention to. So for example if your system has 2 controllers whatever one you press becomes player one. It is still a requirement for games to pass certification and ship on consoles, thus you see it everywhere.",
"It's kind of just for presentation and aesthetics, put some art and music on to set the mood. Like cover art on a book but you can make things move around and add audio. It's a carryover from arcade games when you had to put a quarter in and get up to play the game.",
"They used to not know if you were there to start playing. This was due to long start times on home PCs and arcades.",
"A game is like a restaurant. Before you open it up for customers, you have to run a series of checks to make sure you are ready to serve. Are all the staff needed there? Do you have all the ingredients? Are all the kitchenware, plates and utensils clean? You want to make sure everything you can control is ready before you give the \"start\" for customers to interact with your restaurant. That \"ready\" screen is a checkpoint for the developers to make sure everything is properly loaded before a game starts handling player input."
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8x706v | Why must I constantly adjust the volume of my tv when watching movies, mainly between conversation vs action scenes. I know it helps add to the mood of current scene but just excessive volume range differences. | Technology | explainlikeimfive | {
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"Movie audio is designed for theatres, where the action scenes are best heard ear-splittingly loud (or so thinks Hollywood). Unfortunately this means that turning it down at home to keep the neighbours happy makes the dialogue too quiet. If you have a surround sound system, try turning up the volume on the front centre channel; that's where the dialogue is usually played. I find this works well. Alternatively, some TVs and receivers have a compression option. This just adjusts the volume automatically, turning it down during loud passages and up during the quiet ones.",
"Alot of times this is down to the audio mix. 5.1 vs stereo. Tvs usually take stereo (2 channels of audio, left and right). Cinema and speaker systems can take 5.1 surround sound (6 tracks of audio). This volume change is due to the 5.1 being mixed down to stereo on your TV. So it's putting these 6 channels, flattening them down to two channels and then this causing it not be fmthe ideal mix . This might not be the case all the time but this can cause it. I've noticed this happening with downloading, all the files seem to be 5.1 (6channels)",
"Worked in TV/Movie industry for a few years and did a fair amount of editing in post + transcoding, etc. Basically a surprising number of editors in video are pretty mediocre (or worse) in terms of audio science so their audio levels/balance are shit. Also, as others mentioned, original sound formatting is often compressed and then becomes extra shit. But make no mistake, it's stuff straight from the content creators/producers which is often at fault.",
"TLDR Because movie theaters are like that and many people at home want movie Theatre sound. --- There's a lot of bad answers here. I'm a recent film school graduate, and I just got done mixing my major film in a mixing room, with one of those cool huge mixing desks and a teacher who has worked in the industry for over 40 years mixing sound in films. --- So dynamic range in sound is the difference between the quietest stuff and the loudest stuff. A good example is if you turn on the radio, there is almost no dynamic range. They \"compress\" the songs so that everything is as loud as possible. The problem is, a symphony isn't made for that. If you sit down for an orchestral performance, it gets *loud*. Then, everything might drop out and leave just a quiet, lonely oboe on stage, and you want to lean in to hear it. It makes everything feel alive, and real. Now, a lot of people who love movies want to experience them as intensely as possible. One of my friends has the biggest TV I've ever seen in his live, along with a 5.1 surround system and every time we watch a movie, he turns it up as loud as he can. We watched Detroit last night, and when a gun is fired let me tell you holy shit you could feel it. It's incredibly immersive. As a general rule, when mixing sound for film your goal is to mix for those people. You want to mix for the most immersive, theatrical experience possible. There are so many people that have crazy sound systems and projectors in their houses, and you want to deliver the best content for those crazy avid film fans. The problem comes when you're not one of those people, or you live in an apartment and have neighbors and can't be too loud, or maybe you have family trying to sleep. These things make you *feel* like the volume is too loud, even if it might not be too loud for you. It's just too loud for where you are. Then you have to turn the volume down, but the quietest parts of the movie were designed for the volume to be higher. So then, because you lowered the volume to make the loudest stuff not as intense, the quiet stuff is not even legible. Now, I don't think movies will change. There are too many people who actively want the currently level of dynamic range, and would get angry if you stopped. The easiest solution, if you're not obsessed with the sound quality or don't live somewhere where you can really enjoy the dynamic range, most sound systems have a built in compressor. You can just change the settings on your TV so that it will bring up all of the quiet bits and make them louder! The thing that makes me frustrated is how little they advertise this or teach you how to when you buy the TV or sound system. This is a brilliant invention, because those of us who love dynamic range can still enjoy it, and those who don't can just change the settings on their TV.",
"I ran into some 7.1/5.1- > 2.0 conversions losing a lot of the voice, because it was mixed completely into the center channel; which doesn’t exist in 2.0/2.1. Others have made some good comments on here, so I’ll leave it at that. I do have to disagree about limiters and compression though. Depending on how they are set up, they can “crush” the dynamic range without ruining sound quality. It’s not perfect, but better than fiddling with the volume knob through the whole movie.",
"You haven’t turned on the volume equalization. Find that in settings somewhere and turn it on.",
"Usually it is varying amount of dynamic range compression. During scenes with relatively little dynamic range compression, the quiet sounds and dialog will sink down into the background but during scenes with a lot of dynamic range compression (action scenes and commercials), every sound is forced near the maximum volume the channel supports making the average sound much louder.",
"I can find out for you if you’re interested but I have a sound bar that allows me to adjust sound of voice, sound of music and general sound all separately meaning I normally don’t have to adjust more than once or twice during a movie/show :)"
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8x753a | Why does pasta have numbers on the box? i.e Farafelle no. 65 | Technology | explainlikeimfive | {
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"It's picked up by a biowaste transport company and then incinerated. They have special scrubbers on the exhaust of the incinerator so that no germs accidentally escape.",
"Generally speaking, after it’s been tested, they’ll incinerate it like they do with other medical waste."
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