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jv1nby | What is the difference between Data Warehouse and Data Lake? | Technology | explainlikeimfive | {
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"Data Lake = throwing all your toys into a big pile in a room in your house. Data Warehouse = Putting all your toys in a neat and orderly fashion in a room, labeled and ready for use. Toys that don’t fit how things are organized are never brought into the room."
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jv1nic | What is actually going to happen when Google stops “supporting” Adobe Flash Player? | Does this mean that we will have to pay for a subscription to run anything that requires it? Can anyone explain? | Technology | explainlikeimfive | {
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"It's being disabled entirely for the browser: any websites at this point that still use it (very few outside of very old content and flash games) will not function .",
"No, it means that websites which use Adobe Flash Player will generally not function correctly. The intended solution by Google is for the webmaster to change their site to not use Adobe Flash Player."
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jv1vme | How did people start cars before the modern key-in-ignition system? | In old movies, anyone can start any car without a key (one example is in Bringing Up Baby) Is that just a movie thing? | Technology | explainlikeimfive | {
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"I believe the original Model T used a crank to start. It was in the engine so people had to crank the car and then get inside to drive.",
"The first method was a crank start (dangerous) then you got a push-button electric starter. Eventually moved to keys as a security measure."
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jv3i1w | How was the ISS launched and put into orbit? | Technology | explainlikeimfive | {
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"Carefully... Jokes aside, piece by piece. Mainly using the space shuttle. The big deal of the space shuttle was that it was “the pickup truck” of space craft. It could go up with large cargo, assist in its positioning and assembly then fly back down for another round. This made the ISS viable as sending each piece up into orbit on a one time use despite rocket, or the whole thing up at once, would be impractical to say the least."
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jv40dg | How does the Youtube algorithm works? | Technology | explainlikeimfive | {
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"We don’t know, and we can’t know, even google themselves doesn’t really know how it works 100%, because it’s a self training neural network, basically it tries a lot of things and does what it thinks is the best based on tons of data, there is no answer to how it works",
"Nobody really knows, not even Google, they admit that much. What they use is something called machine learning and while the specifics about that are beyond ELI5, the ELI5 version goes like this: You have a certain goal in mind, say you want to tell apples for pears and you have certain information of each fruit you want to assess in our case, that would be, for example, the height, the width and the colour. Your machine that ought to learn doesn't know anything about apples and pears, as it is a computer that doesn't eat fruit, it only knows that you have three datapoints that you call either apple or pear. It then tries to determine how to tell apples and pears apart by these information. Maybe it will learn that pears tend to be green, while most apples are not. Maybe it learns that pears tend to have more height than width and for apples, these values are more or less equal. Maybe it finds another way we haven't even thought of that is even better for telling these things apart, it simply works backwards from the provided labels (apple or pear) to make an educated guess. Obviously, for Youtube, this concept becomes way more complicated, there a billion more variables about you. Google might have information about you, what gender you are, how old you are, where you're from, how much money you have and for each of these pieces of information, they have an attatched certainty on how sure they think they are right about them. (For example, having the opinion that you're 18-25 with a certainty of 75%, 13-17 with a 20% chance and 25+ with a 5% chance) and also the idea of categorizing \"right\" becomes more complicated. What is \"right\" in this context? Google has set different directives for that in the past, making \"right\" the amount of times people clicked your video, how many likes it got, how many times it was viewed or how many times people commented. Currently, the goal that Youtube has set is to increase overall watch time on the side. (Not surprising, they want you to watch ads after all) So the most ELI5 version of it would be: Google is setting the goal of keeping you watch as long as possible, for this they use every bit of information about you and the world they can get and they are constantly testing which bit of information and what combinations of information they have to value how high to make you watch as long as possible."
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jv6emm | With modern technology, why are all types of printers still so slow and embarrassingly unreliable? | Technology | explainlikeimfive | {
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"Not all are. Just the cheap consumer grade printers are terrible. If you are willing to put a few thousand on the table you're able to buy a reliable machine that pushes out your 300 page report in a few minutes."
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jv8hgu | Why do older TVs and radios translate weak or missing analog signals as "static?" | And on a related note, why do more modern radios now play silence instead? | Technology | explainlikeimfive | {
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"It's about how the signal is encoded. Analog signals will simply play the wave that is send, and in case of nothing send it will amplify the background noise. Digital signals are basically numbers encoded into the radiowaves you then use to generate the sounds. They can use checksum bits to verify that meaningful things were sent. If nonsense would be received it simply won't be played."
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jv9u78 | Why do we need to modulate digital signal? | Hello, i know that, we modulate digital signal to reduce noise and to make it possible to travel wirelessly. But i also read that modulation can help digital signal reach greater distances, but i didn't get it how. Can you explain to me how digital modulation helps digital signal reach greater distances? Do you know any other needs for digital modulation? | Technology | explainlikeimfive | {
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"Modulation is a very wide term for changing a signal. So it is very hard to process any signals without doing something which could be considered modulating it. In radio transmissions you need to change the frequency to a high frequency signal so that it will match the size of your transmitter and antenna. But there are lots of other uses for a MOdulater/DEModulator to change the signals for transmission. Modems are used to transfer signals though everything from phone wires to fiber optics."
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jvmta6 | What is ray tracing? | Technology | explainlikeimfive | {
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"> Like, when you create an object like a sphere in a modeling software, doesn't the computer already know what the object looks like from any angle. Yes, but no. If you make a sphere and put a texture on it, now you have a textured sphere. But how is it lit? How do light sources in the scene reflect off it? Does it show any specular reflections if it's a shiny metal? How do you know how exactly to draw the light on it? Traditional rendering would require such considerations to be \"baked in\" to the scene -- that is, computed when the scene is drawn in a way that can't change in real time as things change. Ray-tracing changes the game; it seeks to mimic the way light would actually behave in real time, tracing the rays as they travel through space. The computer repeatedly draws rays traveling away from the camera and bouncing off of objects in the scene until they reach a light source, and then uses that information to compute how the objects they bounced off should be lit. This happens in real time, so things like reflections and fire and shadow and lighting can look a hell of a lot more realistic."
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jvpdia | How does google maps or waze figure out what speed you are moving on ? | Technology | explainlikeimfive | {
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"The app monitors your position and based on how far you've traveled since it last checked it can determine speed",
"Smart phones have GPS receivers built in part of the function of a GPS receiver is to locate your position...it simple math to figure out you used to there and now you're here and it took you a certain amount of time to get there and that means you are traveling at xx MPH"
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jvq1nj | What does it mean when a phone is factory unlocked? | I've been asking Google for a while now but I am still confused between the difference of factory unlocked, OEM, and original. I'm planning to get my mom a Iphone and I don't want to get her a fake. | Technology | explainlikeimfive | {
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"It just means it's not locked to a specific phone provider and you can use it with any provider.",
"Probably safest to get it from the Apple Store (to make sure that it’s unlocked). If you get it from somewhere else you should expect it to have a similar price (any significant discounts probably mean that it’s in a contract and might also be locked).",
"Cell Phones used to be subsidized by the phone company, or you leased a phone from them. To prevent you from taking the phone and using it with a different phone company the cell phone service provider would have the cell phone manufacturer make a particular type of radio chip and antenna for that frequency/technology. For example Verizon was.cdma, sprint was tdma and att and T-Mobile was gsm. All on different frequencies and radio technology. But then the cell phone manufacturer would have to build 3 different types of phones, firmware etc. It was cheaper to build 1 phone and have the ability to use any network and lock it in the firmware to a particular carrier. Now with many changes in laws about how you're locked into a contract, phones tend not to come locked in most jurisdictions."
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jvqb1m | How do Youtube channels like MrSuicideSheep, ChilledCow, CafeMusic, etc. make money using other peoples music? | Technology | explainlikeimfive | {
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"I'm unfamiliar with any of those channels, but I glanced at MrSuicideSheep and it looks like he's doing a few different things. Some have a commercial creative commons license that allows him to make money from them with attribution, which he seems to be doing. Some don't have a CC license and the music is 'claimed' by the record label. In those cases, he more than likely is unable to retain any ad revenue from the video, it would go to the rights holder. Or for some of those, he may have purchased a license to upload the song in that form on YouTube and so even if it's claimed, it won't take away his earnings. Some also seem to use neither of those, but rather have the artist's info simply listed in the description. Those may be cases of him just taking other people's music and uploading it illegally, or he may be doing it with their permission, or perhaps he allows for people to pay him to put their music on his channel. & #x200B; I'm not a fan of channels like that because it's very rare that they'll fully pay the artists for the use of their song in a way that's making the channel money, but it looks like MrSuicideSheep is likely doing it properly? Or he just doesn't care if he makes money from ad rev because he sells enough merch that it makes up for the ones he steals. Without knowing how he does it behind the scenes, it's hard to say."
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jvrlsc | Why does x64 means 64 bits and x86 means 32 bits? Why not x32? | Technology | explainlikeimfive | {
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"Because the architecture was made for the Intel 386 and 486 (collectively x86) processors in the late 1980s. The proper name for the 64bit architecture is x86-64 or AMD64 after the company who developed the extension to the old system.",
"The current family of processors started with the Intel 8086. The next processor in line was the Intel 80186 which were backwards compatible but added new features, then came the 80286, 80386, etc. First people shortened it by removing the '80', so it baceme the 386, 486, 586, etc. but as there was now less difference between them other then optional features of the architecture the entire line of processors were just shortened to x86 which stuck. Note that AMD did also produce compatible processors thanks to a requirement by IBM that Intel should have competitors in order to be able to bid on IBM contracts. But AMD was able to further develop the platform and came out with their 64 bit architecture called AMD64. Intel soon copied them but instead of calling their standard after the competitor they called it the x86\\_64 which have now become more standard. However this too will often get shortened to just x64.",
"The original 8086 had a 16 bit data bus and a 20 bit address bus. The 80286 had a 16 bit data bus and a 24 bit address bus. The 80386 was the first of the 32 bit chips and by that time the x86 moniker had come to mean \"instruction set based on the Intel 8086 family of chips\" AMD introduced a 64 bit instruction set that was better accepted than Intels' 64 bit instruction set, to the point that Intel ended up adopting it. That's where the new moniker came from.",
"**TL;DR** While x86 includes all 32 and 64 bit x86 family processors, it was traditionally used for Intel compatible 32 bit processors, and now that we call the newer processors x64, people have reverted to x86 for the older processors. **A little background** 8086 = 16 bit microprocessor, 16 bit address bus = 1MB Max RAM 80286 = 16 bit Microprocessor, 24 bit address bus = 16MB Max RAM 80386 = 32 bit microprocessor, 32 bit address bus = 4GB Max RAM 80486 = 32 bit microprocessor, 32 bit address bus = 4GB Max RAM 80586+ = 32 bit microprocessor, 32 bit address bus = 4GB Max RAM (Pentium, pent = 5) As you can see, these 80x86 processors were collectively known as the x86 range. *(Not shown is the HUGELY popular 8088 which succeeded the 8086, and the never sold as a PC 80186. The 80286 was also never intended to be a PC processor, but things didn't turn out like Intel planned).* Intel licensed the brand early on, and AMD & VIA manufactured x86 compatible processors under license. Most modern processors no longer carry the name 86 anywhere, but are still considered part of the x86 family. **Problems with 64 bit** Long story short, Intel couldn't create a processor that could efficiently run 32 and 64 bit code, so they created a dedicated 64 bit processor, and started marketing 32 bit and 64 bit separately - The 64 bit computers known as IA64 (Intel Architecture) and deliberately not marketed as x86 compatible because they were not - PC (x86) Operating systems (DOS, Windows 95) could not run on 64 bit Intel, only Server operating systems (\\*Nix, NT, ...) could. So no 64 bit for home users. BUT, AMD found a way to get their processor to be able to do 32 and 64 bit switching efficiently in real time, and soon licensed this AMD64 tech to Intel. Intel were now producing their IA64 (server OS only) 64 bit only processors, the older x86-32 (any OS) processors, and the newer x86-64 (any OS including 64 bit server OS) processors. Intel stopped manufacturing the x86-32 processors (normal end of life) and soon there was only x86-64 left. AMD64 could refer to a 64 bit AMD chip specifically OR AMD's 64 bit extensions on Intel chips, and since x86-64 made little sense since there was no longer an x86-32 (32 bit) processor range to differentiate from, people shortened x86-64 to x64, and referred to the pure Intel (and last real Intel only) chips as x86. And so here we are."
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jvrrky | What’s the difference between file compression types (specifically zip and rar)? | Technology | explainlikeimfive | {
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"Generally speaking, ZIP is a more variable format. RAR is proprietary, i.e. it belongs to a specific company and it costs money to use it. It has a specific kind of compression algorithm. It naturally supports password protection. ZIP is an open format, i.e. it's free to use (for the most part). It also supports several different compression algorithms. The basic format doesn't support password protection, but since it's an open format, it has extensions that do.",
"Good question, never really asked myself so I just googled : RAR creates a smaller filesize compared to ZIP in many cases, sometimes by a large margin. The difference, however, varies depending on the size and type of files being compressed. Based on this file compression benchmark test, WinRAR can compress a 310 MB test file to 90 MB. That’s a 71% compression ratio. WinZIP, on the other hand, can only compress the test file down to 125 MB, or just 60% compression ratio. So basicly, they both do the samething but RAR is more efficient. ZIP's advantage is 'availabily', since RAR decompressing applications will require a license to be used... even tho I remember all those memes about winRAR and people who pay for it lol Theres more specific details in the link i found Source : URL_0 .",
"edit2: I misread the question ignore all this. Tar is not a compression system. Tar stands for Tape Archive and simply packages many files into a single file or, more generally, byte stream, originally meant to send to tape recorders. A typical “tarball” meant for distribution gets compressed with gzip, therefore being a .tar.gz or a .tgz for short. So the real question is what’s the difference between zip, gzip, and all other compression formats (like 7zip, xz, etc...) I don’t know the exact implementation details for each of them but usually the differing factors between compression algorithms are speed and compression factor. The ideal compression algorithm has a compression factor that’s as high as possible while having a speed also as high as possible. In practice usually compressing data more hurts speed and compressing data faster hurts the compression factor. Some algorithms are tunable for these factors as well. Edit: didn’t know this was eli5. Here’s the eli5 Tar is like taking a bunch of cardboard boxes and putting them neatly in a shipping crate Zip is like unfolding the cardboard boxes so they lay flat and take up less space."
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jvxu7x | What is the physical mechanism that translates between hardware and software? | Software is just memory, stored on a physical device. How does that hardware actually read or write, and how does that physicality manifest as software? | Technology | explainlikeimfive | {
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"That memory is addressible, the chip has address lines that tell it which location you want and data lines that the chip puts the data on. The processor has a register, called the Program Counter, where it stores the address of the next instruction in the program. What a CPU chip does is: 1) Put PC on address lines 2) Activate memory chip 3) Copy data from data lines into operation register. 4) Increment PC 5) Decode and execute operation register contents 6) goto 1"
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jvy5am | What are data silos and how do they work? | Just trying to get a basic understanding of it. | Technology | explainlikeimfive | {
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"A data silo is basically a subdivision of the way parts of a company looks at information. Some departments don't care about certain information and don't need all the information, so each department can set up its own data silo and really organize the data they care about One example might be... a marketing departments database might have a lot of schemas, tables, information around campaigns, advertisements, cost-per-click, cost-per-sign up, etc etc An accounting department's data silo would probably just have a marketing campaign as a line item with an associated cost to the business."
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jvze2a | How does data take up physical space on a hard drive (or SSD)? Isn't it all just ones and zeros? | Technology | explainlikeimfive | {
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"Data doesn't take up physical space, but the more or less light switches that represent it do. One, or On, or True, or high voltage is one state. Zero, or Off, or False, or no voltage or negative voltage is the other state. If you wanted to represent 1 kb of data, you're going to need at least 1000 switches, as you have 1000 on-off states to represent. If you're using actual light switches, that's going to be pretty damn big, you're going to need a whole room. If you're using nanometre scale switches called transistors, you can fit a few trillion of the switches on a solid-state drive. Hard drive is a bit different, the switches are magnetic. It's a bunch of North and South poles to represent the 1's and 0's, but there's a limit to how small we can make each magnet, so a hard drive also has a physical size limit. A CD is again different. It's a bunch of tiny pits/holes in the disc that determine if a later bounces off or not. Again, there's a limit to how small you can make the pits, and how tight your laser is for reading them. Again, a physical size. There is a true, fundamental physical limit between data (also know as information or entropy) and space and energy, but none of our storage technologies are even close to this. Breaking this limit is a black hole. After which, you may irrevocably lose the data forever to the black hole, or maybe slowly gain it back over billions of years. Jury is still out on that one. This has nothing to do with actual storage technology, that's just a limit to our engineering ability to make a tiny switch of some sort.",
"It's easier to visualize and explain for hard drives, but some physical property of the storage media has to be altered so that when that same position is later read from, the correct value is obtained. For a hard drive, this is done by altering the magnetic properties on specific spaces of a magnetic platter. Metaphorically, this can be compared to the equivalent of flipping specific switches on a giant wall of light switches. The position of those switches can then later be read to determine the data stored there."
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jw21bj | Why are ARM processors more power-efficient (performance/watt) than x86 processors? | I was looking at some performance metrics of Apple's new M1 processor, and it's interesting that performance per watt is really good as compared to Intel processors, and also AMD x86 processors. That kind of confuses me, because I know that there's the decoding stage where x86 instructions have to be turned into other instructions to actually be executed by the processor. But my understanding is that the performance penalty for this decoding is very, very minimal in the modern day because that percentage of transistors used for that function becomes smaller and smaller compared to the processor as a whole. So, how is it that ARM processors can be so much more power efficient than an x86 processor (lithography process and all that otherwise being equal)? | Technology | explainlikeimfive | {
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"The M1 core is much wider than their x86 compatriots. The M1 on a per core basis has 2.5x as many micro-ops in flight, has extra execution resources, and more memory bandwidth compared to a typical x86 system. The downside to this approach means extra transistors which means less CPUs per wafer. Because of this, they don't need to scale frequency as hard. The M1 in its high performance state runs at 3.2GHz. In comparison, a Tiger Lake core will often go north of 4GHz for periods of time where thermals allow it. Once you start getting into higher frequencies, power usage starts to go up exponentially. By staying at the bottom of the curve, and instead going for a wider execution core, Apple maintains a huge power advantage."
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jw4iaw | How does Docker and Kubernetes work? | Technology | explainlikeimfive | {
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"Think of docker as a \"virtual machine lite\". You can package your application and all of its supporting libraries and configuration files into a docker container and run it as a standalone package without having to worry about the system admins getting the right versions of stuff loaded or some incompatibility between the library your app needs vs another app. But you can't run a docker container for something like Windows on a Linux box, which is why I called it a \"virtual machine lite\". Kubernetes is a container orchestration system. it lets you deploy containers across servers, manages the containers if they die or if the host machine the containers are running on crashes. It lets you scale up/down (crap, server overloaded...need to run another 30 containers to handle the load!)."
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jw8w6q | When looking at a computer screen from an angle, why are the colors distorted? | Technology | explainlikeimfive | {
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"This depends heavily on the display technology and the viewing angle it’s setup for. Usually you see this behavior in cheaper or older LCD screens specifically the TFT type. IPS displays like on macs or oled displays don’t really have this issue as they have a much wider viewing angle."
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jwbdyu | How do satellite dishes for tv (Direct TV for example) communicate with satellites when there so small and pointed at a small area in the sky? | Technology | explainlikeimfive | {
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"They don't communicate with the satellite, they just receive a broadcast. The satellite broadcasts over a large area and every satellite dish in that area can receive the broadcast.",
"Well that dish thing is what helps. It reflects the broadcast into the very small point on the receiver. Consider this the focal point. Kind of amplifies it Thankfully as well. Your dish doesn’t need to send data back, only receive. It can be relatively small, where as the one in space is very powerful and broadcasts over a massive area",
"Used to work for Dish Network. So, the dish *generally* doesn't talk back up to the satellite. It's possible, but it requires a different dish and setup, and it's only used for satellite internet, which isn't what you were asking about. It helps to think of the radio signals as a flashlight beam in a dark field. The little white lens part at the tip of the dish is called the low-noise block feed, or LNBF. *That* is the actual \"antenna\" and the rest of the dish is just a reflector to better focus the \"light\" of the signal. It doesn't need to be pointed *directly* at the satellite, but it's got to be pretty damn accurate by human eyeball and hand tool standards. \"Accurate\" in terms of what your home garage tools can do and \"accurate\" in terms of spacecraft 22 thousand miles up are two *vastly* different things. The reflective dish makes that accuracy requirement a lot more flexible, and also affords a stronger signal to compensate for things like rain and clouds. But all your receiver really needs to do is look at the equivalent of a flashlight in the sky, and determine the code from its blinking. Regular computer magic turns that really fast blinking into a data stream into video for your TV.",
"Revcieving a signal is all about signal to noise. You can generally amplify a signal as much as you want, but it also amplifies the noise. The dish amplifies signals only from the direction it's pointed, and there's not a whole lot of other transmitters in space since putting satellites up there is expensive. Add onto that satellites are generally allowed to broadcast at a much higher wattage, than say your cell phone or wifi. Wattage limits are based on the risk of interfering with other signals. So on earth you can't just have a 100W WiFi router because it would ruin wifi for everyone else miles around. Satellites are more well planed and regulated, and of course there's less of them. Add on to that that most signal loss for ground transmitters is limited due to line of sight from the curvature of the earth. Antenna towers are tall to avoid having to transmit through the ground or through buildings, trees, etc. And add onto that that even signal loss travelling through air is fairly limited. The atmosphere is mostly all concentrated in the lowest 10 miles. Traveling through space there's no signal loss, from traveling through vacuum."
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jwcm4l | How do computer frames work? | The frame gets the destination/source MAC address, the router uses the packet's IP address, but the router sends the frame? I don't get that. Does the router read the packet inside the frame? So it knows the IP address it's going to send the frame to? | Technology | explainlikeimfive | {
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"Yup. The mac address is mostly for the sender and receiver to identify each other, and is needed for doing things like NAT which is what allows 20 computers in a house to share one up address. But the ip address is what important for routing, so routers have to be able to read and interpret ip headers. They also do a small bit of math to calculate the frame check, but it's simple math that doesn't use much more processing power than just receiving data on one port and transmitting it in another. Most routers are also capable of limited interpretation of the ip packets data as well, at least identifying things like port number or http requests for quality of service and filtering."
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jwewpk | Why does Minecraft have to look like a game for the Commodore 64? | Technology | explainlikeimfive | {
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"Answer: That's an aesthetic choice. It doesn't look the way it does because of technical limitations. There are many other successful modern games that went for that retro/pixelated look, and Minecraft isn't alone in that (Terraria, Enter The Gungeon, Celeste, Shovel Knight, etc). And I am just writing more than one sentence because this sub requires me to do so. But yeah, there's not much more to say about it.",
"Minecraft looks nothing like a game for the C64. This sort of graphics would not have been possible on a C64. They actually require quite a bit of computing power to make work. The original developer made a stylistic choice about how the game should look. The choice of making everything out of blocks does not mean that the graphics have a low resolution. If you don't like the texture of the blocks there are a million of skins that make them look differently. The choice of style has nothing to do with technological capabilities and only looks retro and like from the 90s if you didn't actually live through them.",
"Because that was the developer's choice. He was inspired heavily by a previous game called Infiniminer which had the same blocky visual and gameplay styles."
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jwgqsa | Why would a computer monitor need an ethernet jack and output jacks? | In reviewing monitors, I came upon this Dell monitor, the Dell UltraSharp 27 USB-C Hub Monitor - U2721DE. With all of the other bells and whistles, it comes with an RJ45 ethernet jack and what appears to be not only a Display Port (IN) but also a Display Port (out). So for the life of me, I cannot figure out why either of those two ports are something I would want? 1. What's the reason for connecting a monitor to my network? 2. I get the different input options, but why would I be outputting video from my monitor? I'd love to understand what cases there may be for these options. [ URL_0 ]( URL_0 ) | Technology | explainlikeimfive | {
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"You can connect your laptop to it via USB-C and get wired ethernet through it instead of always using wifi. Same with your mouse and keyboard. It's like a docking station.",
"This monitor isn’t intended to be a peripheral for a desktop PC, it’s part of a workstation setup where you’re connecting a laptop to it. The monitor itself then provides wired power and internet connectivity to the laptop - that presumably belongs to someone who is often working remotely or in the field. Video *out* on a monitor may be useful if you’re planning to be running presentations on another screen somewhere.",
"This thing works like a dock for a notebook: All devices, power cable and ethernet plug into the screen, and then your notebook connects to the screen with a single USB C connector.",
"Modern ultrabooks have shifted to having just a couple (sometimes only 1) USB C ports which can connect to accessories and also serve as the charger. You can't make an ultra thin laptop if you put an Ethernet jack on it because the Ethernet jack is thicker than some of these laptops The monitor is meant to serve as a dock so instead of hooking your laptop to a dock which is hooked to your mouse, keyboard, monitor, and ethernet, you instead just connect the USB C port to the monitor and it sends the video data down that link like a Display Port, and connects to the accessories hooked into the monitor like Ethernet, other USB devices, and even daisy chained devices. Display Port supports daisy chaining displays so you can take a single display port cable, run it to one display, hook that display to another, and hook *that* display to a third to have your GPU control 3 screens from a single Display Port cable. This helps clean up the mess of wires that traditionally runs behind a desk. The goal of this screen is that when you get to your desk you hook up a single cable from the screen to the laptop and you're done. Your wireless mouse and keyboard are already hooked to the screen, your ethernet is hooked to the screen along with power, and you really only have 3 total cables on your whole desk."
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jwh6j9 | What's the logic behind compressed files like .zip and .rar? | Technology | explainlikeimfive | {
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"The logic is pretty simple, instead of representing the data in raw form you find patterns in the data and use those. Example: aaaaaaaaaa can be represented as 10a because there are 10 a’s, it takes up way less space and can be decompressed to the original raw data without any data loss (lossless) Each compression scheme (algorithm) has its own way of finding patterns.",
"For general purpose compression, the idea is that you find a sequence that is repeated multiple times in the data you're compressing, and then replace those with references to a dictionary that contains that sequence exactly once. Let's say you start with the text of Green Eggs and Ham. There are 50 different words in that story. You make a list of all those words, give them a number, and then replace the instances of the word in the text with that number. Now every single word is replaced with a 1 or 2 digit number. You can then do the same thing again with those results and see if it's significantly smaller. You'll likely hit the repeated word sequences next (the \"I do not like...\" phrases). You can then shrink those down to become a reference of references. As long as you keep getting smaller each iteration, you can keep going."
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jwivdr | Why does turning a computer (or things like it) off usually solve the problem? | Technology | explainlikeimfive | {
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"You ever play the game 'telephone' as a kid? Where a bunch of kids would get in a line and whisper a message to the next kid in line, and by the end what the last kid heard was nothing like what the first kid said? It is kind of like that. Programs are, at their core, very simple things. They take an input, perform a task, and produce an output. Then, another part of the program takes that output as _its_ input, performs a task, and produces its own output. Now, just like in our game of telephone, errors do happen. Just as a kid my mess up their message and pass along a mistaken phrase, a task can make a mistake and produce a bad output. Computers can deal with this to an extent, but eventually errors can get so bad that the outputs aren't useful as inputs to other tasks, and the program begins to suffer for it. Once the message gets so garbled, the only thing you can really do is start over. Rebooting the computer starts the tasks over from scratch, so they can start using good inputs again.",
"It’s like doing a long math question on paper. if you make a mistake somewhere, it’s easier to start over new than try and correct it as you go",
"Software can be thought of as a cooking recipe. Programmers writing the recipe, and the computers being the chefs, following the recipe. Unfortunately, computers are bad chefs with no souls, and will always follow the recipe EXACTLY, to the letter, with NO deviation. They can't even taste the food. If the food starts tasting wrong, they'll never know, and will just keep following the recipe. So you've got your dumb computer chef who will never ever go off recipe. It's usually fine, he can make you a thousand soups a day perfectly. But one day, some accident happens and some soup he's cooking you is suddenly WAY too salty. What do you do? You could add a step into the recipe to add lemon juice, just this one time to save this one soup, to cancel the salt, but you aren't a programmer, so you aren't gonna change the recipe. But the thing you CAN do is pour out the salty soup, hand him the empty pot, and tell him to make an entirely new soup. And as long as whatever caused all the salt doesn't happen every time he makes soup (which it probably doesn't), this is will always result in good soup!",
"Another reason that I haven't seen mentioned too often is that it is harder to test issues that require software to stay running for a long time. For example, a new version of Windows is tested by first installing it and then doing some simple tasks after a restart. You don't just keep using it just in case something stops working when some timer reaches 42 days or the memory gets too fragmented or whatever (made up issues). It is also incredibly hard to reproduce issues that only happen after it has been running for a long time, as you have to give it the same inputs again, which you probably don't remember a week later. And if you can't reproduce something, it is incredibly hard to check that changing the code fixed it. Therefore it is usually easier to tell users to restart their system, and since they are used to it, noone complains (there are nore inportant issues to resolve first anyway).",
"Electronic devices generally work as expected when they've just been turned on. That's how they were tested. If they didn't work as expected straight away, they probably would've never been packaged and shipped. When things run for a long time, stuff happens - like maybe a build up of things getting stored in memory, or maybe a working part of the device / software was turned off or altered making it not work as effectively any more etc. Restarting it basically returns it back to its original \"expected\" state. Memory gets cleared, any changes are reset etc. Opinion ahead; I disagree with a lot of the other answers here that talk about guesses and data corruption. If a device is designed / coded properly it should run exactly the same regardless of how long its been running. Sure there are potential external factors that could effect the program / device or whatever but generally speaking, if it's a self contained unit, the designers / coders should have accounted for the potential effects running for a long time may have on it. A Linux server can run for months without being rebooted and work just as fast as the day it booted up.",
"It rarely solves the problem, it usually just eliminates the symptom. Often temporarily; the underlying cause is still there, all it takes is the same series of events to trigger the same symptoms. It's not unlike taking a lozenge if your throat is sore, that in itself didn't cure whatever caused the sore throat in the first place, it just addressed the symptoms.",
"I liked an analogy I heard about this involving a chess game. Say you're playing chess with a friend, the game's going on for a long time, and at some point you notice both your bishops are on white squares, which is an invalid board state. (If you don't know chess rules, the bishops start on opposite colored squares, and only move diagonally, so they can't switch colors.) If you've taken very careful notes of every move made thus far, it might be possible to undo them one by one until you find where you messed up and fix it, but it's a lot easier to just reset the board. This is even more the case with a computer, which has a lot more going on than a chess game, and rarely if ever logs *everything* that happens while it's running.",
"Usually, when a computer is having the sorts of issues that are fixed this way, it's due to resources being hogged. It could be possible for you as a user to hunt down the mismanaged resources and force them away from whatever is hogging them. But it's often easier, especially on \"user friendly\" platforms, to restart the machine, and then the resources are reset to a neutral state. Typically, the Operating System (OS) has oversight of all the available physical resources. It may lend permissions to these resources to programs, applications, or processes that ask to use them. Then the programs etc are expected to let the OS know when they're done using the resources. It's when they fail to do this, that you'll have problems. For instance, a program may need some active/working memory, such as RAM (Random Access Memory). -- Physically, RAM takes very little time to be read or written to by the processor. This makes it great for storing information that's changing rapidly, like if you're playing a game, or even something tamer as when you're just typing a paper, and the text data is growing and changing as you work. -- But the amount of memory the program needs may vary as the program runs, and it's actually very easy for a program to fail to relinquish the memory it has asked for. This means less available memory for all subsequent programs. When the fast memory in RAM gets used up, the OS may need to rely on hard disk space for working memory, which is a lot slower. Time on the processor is another resource. Your programs are not actually all running simultaneously. Essentially, there is only one operation happening at a time (or, per clock cycle), per processor core. The OS plans which program gets to use the next operation on any given core. But sometimes, a program may have requested to perform a set of operations that have no end condition, or which the program may have forgotten about. Even if the OS is not continually dedicating a core to this process, it's still taking away from processing time that could be better spent on something else. There are other hangups that can happen as well. Whatever the OS, there are \"environmental\" variables, or data, that programs may ask permission to read or to change. Some of these variables are important enough that programs are only allowed access one-at-a-time. So, occasionally, a sort of catch-22 will occur between two programs asking for the same variables, where they both have access to a variable the other needs, and neither will continue their progress nor release what they have, until they can access the other variable. Overall, modern operating systems have much better strategies for dealing with these issues, than they had in the past. But past or present, a skilled user may be able to consistently avoid, or track down and amend these types of issues without powering down (which is important on something like a server, or perhaps a super computer that's crunching complex problems all day). But for the common user, fixing it manually is too tedious, and it's easier to start up with a fresh slate of RAM and all that."
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jwkb49 | What is machine learning? | Technology | explainlikeimfive | {
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"A machine that attempts to solve a problem and not only learns better how to solve the task, but also what ways to go about learning the task.",
"In Traditional Computing, you have data, and you run them through rules, and you get an answer. Imagine a Breakout game with a ball bouncing off bricks. You have data, which is the position of the ball. You have rules, which define, say, how the ball behaves when it hits a brick, and you have an answer - where the ball ends up after hitting a brick. In Machine Learning, this is flipped around. You feed in data and answers, and the Machine works out the rules. Imagine you have a fitness tracker device, like a Fitbit, and you want to use it to recognise activities. In traditional programming, you could say something like **if speed < 4, activity = walking**. Then you could say **if speed > 4, activity = running**. Then you could say **if speed > 4 but < 10, activity = biking**. You can see how this could get complicated. What about, say, playing golf? How would you define a rule for that? What about the fact that some people might walk faster than '4'? And so on. It would be incredibly difficult to define rules that categorise all the different activities people might do. With machine learning, you can have everyone with your fitness tracker say \"I'm walking\", \"I'm cycling\" or whatever, and then record all that data. You now have data - the users' speed, and an answer \"this is walking\". The machine can then learn what 'walking' looks like. The more data you can feed in, the better - this is why machine learning uses big data sets. The more examples of something you can feed in, the more accurately the machine can learn."
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jwn1im | How does 2FA remain secure when most people have saved passwords or credentials/"remember me" on one single device, usually their smartphone; potentially a single point of failure? For that matter, why only 2FA and not 3 or 5FA? | For clarification, some banking apps simply require a seperate password in a seperate app to be entered, emulating the same concept that Google Authenticator employs. How is this more secure than say, having a secondary password field in the main app? | Technology | explainlikeimfive | {
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"With 2FA you have to have access to both authenticating devices. Putting both on one page defeats the purpose. The idea is that the chances are much less that a \"bad guy\" will have access to both the site and your phone (assuming of course they are not accessing the site on your phone). The reason anything greater than 2FA is rarely if ever used is end user convenience. Not many people have the ability or desire to authenticate on 3 different platforms and I have to imagine keeping 3 levels of authentication in sync would be more effort than it is worth for daily use",
"2FA saves you from someone who bought a list of login details from a data breach, for example. Before 2FA became popular, stealing login info worked great because the login could be done from anywhere. When an account is protected with 2FA, this mystery criminal can't do anything even if they have your correct password.",
"Not all \"factors\" are equal. For example, having two different passwords is basically the same as just having one, longer password. So having a second password field really doesn't make it 2FA. Generally, the factors should be of different kinds, the three kinds being: * Something you know (e.g. a password) * Something you have (e.g. a smart phone) * Something you are (e.g. finger prints/retina) 2FA commonly employs the first two. The smart phone is something you have and the password you enter into it is something you know. Yes, this means if you enable your device to save and autofill the password part (and your phone isn't additionally protected with a pin or a passcode to get into it) then you have effectively eliminated one factor from consideration; All someone needs is your phone and they get in. That doesn't make 2FA inherently less secure. Just about any security system can be rendered insecure by poor implementation or decisions on part of the users. As to why it isn't 3FA or 5FA. As I point out above, there are only 3 \"kinds\" of factors and having two factors from the same category really doesn't add anything. So the highest you can go and have significant additional security is 3FA but that means biometrics. Biometrics are generally costlier or, when they aren't costlier, less reliable, or otherwise have privacy concerns. Theoretically you could implement this yourself by locking your phone with face recognition or finger print scanner in order to access the 2FA app on it."
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jwo9zg | How do some libraries run out of eBook? | Technology | explainlikeimfive | {
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"The company that sells the eBooks to the library doesn't want there to be an infinite number of people reading their eBook at once, so they are artificially limiting the number of people who can \"check out\" an eBook at the same time."
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jwpvzi | - Why has website design moved from clear tidy spaced pages to massive buttons that require excessive scrolling on almost all devices? (Most notably online banking and govt websites) | Technology | explainlikeimfive | {
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"Can't say I've noticed this with my bank. I'd guess it's around accessibility. You need to provide a service that works for the elderly, people with issues with sight such as colour blindness etc. So to provide a service that works for something like a bank it has to work for everyone. It would be pointless to provide a swish looking site that was unaccessible and could potentially lead to fines etc if you were seen to be excluding people with disabilities or a specific group of people.",
"It primarily comes down to mobile computing. You can design the site to display differently depending on whether the server detects a mobile or desktop browser, or you can design it a single way to save money, in which case you have to optimize for mobile users, which can also function acceptably for desktop. Banks and government sites are much more likely to half-ass that stuff.",
"I’m a UX designer (currently working in healthcare tech). UX designers create how apps and webpages look, while taking user needs into consideration. It is because of accessibility. Bigger buttons and form fields are easier to tap for those with mobility issues. Since Apple and Android have accessibility features of their OS, a lot more people with disabilities can use smartphones. Apps are an extension of that. And due to ADA, you can sue someone over their website not fitting accessibility standards: URL_0 Accessibility standards are extremely complicated to go into detail about, but it’s called WCAG 2.0 (or 2.1) if you want to go into it. While I agree that it does make websites annoying (I am currently working on a page with a massive amount of scrolling!), it does help more people use the internet that might have not been able to back in the days of cleaner pages.",
"I've noticed the same thing over the years. Even bootstrap (one of the most common layout frameworks) has huge margins/padding by default around everything. Can't agree with others about it being because it's designed for phones also these days as it allows vastly different sizes/layouts depending on the device very easily. The markets are changing and more older people are needing bigger buttons and text. Watching my 75 year old mother try and use the web is painful, a simple button click is a challenge for her. The only answer I can surmise is that bootstrap is so commonly used, that people leave the defaults which are big buttons, margins ect which means less room on the page so more scrolling. Also infinite scrolling has gotten more popular as SPA's (single page apps) have become more common. Not reloading the entire page means a quicker response and less data being sent (also paid for).",
"What I hate are the \"load more\" at the bottom of pages instead of just paginating! Endless scrolling and \"load more\" are the worst \"innovations\" of \"modern\" web design. I feel weird with so many quotes but I think it's necessary."
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jwr1ow | Why are digital videodisc formats strictly locked to one resolution and framerate? Assuming it's otherwise encoded to specification, why can't we have 1080p DVD-Video or 480p BDMV? | This might be more of an ELI12 because I already have a pretty good functional understanding of video codecs and the restrictions of physical digital media (so I understand why you can't encode a DVD in something other than MPEG-2, and that you can't fit a 1080p feature film encoded in MPEG-2 on a DVD, for example). But I don't get why a strict resolution is necessary if a stream otherwise conforms to codec and max bitrate restrictions. Are hardware decoders like those in dedicated players substantially cheaper if they only have to expect one or two types of incoming stream? Is it a brand image thing where movie studios and the DVD/BD licensors are trying to create a uniform experience to increase buy-in and retention? | Technology | explainlikeimfive | {
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"Resolution? Because you needed to output something a CRT TV of the time could display and DVD was basically at the maximum resolution already. Most TVs expected lines to match their country's TV specs. In the case of the NTSC aligned regions it was 480 lines visible out of 525 total while in PAL land it was 576 lines visible out of 625 total. CRTs used electron guns and the deflection coils needed time to have their voltage change so drastically so there was a vblank period that took up part of the frame, hence 480 and 576 lines rather than the full 525 or 625 lines. Likewise, frame rate conversion usually had artifacts, was terrible, and wasn't really possible with cheap hardware in 1997. Plus TVs didn't really do well with changing frame rates if they were older and you couldn't be assured that the TV would even be able to display what the DVD player output if it deviated from its country's standard output format. It would be possible to display a DVD at certain lower resolutions and some pirated stuff indeed did but what was the point? You wanted to fit a movie that was as high quality as possible and the space available let you do that, short of a four hour movie. BD is pretty much similar. You get 100GB of data on a disc, players that are engineered to take 1080p, why bother shitting up your presentation for what is effectively shits and giggles?"
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jwrf8j | Why does RAM memory disappear when power switches off, but HD/SSD memory stays intact regardless of power status? | Technology | explainlikeimfive | {
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"Because of its design. RAM stores bits in a bunch of capacitors. These are devices that store electricity in them, but can't do so for very long, they need to be periodically refilled and there is circuity to refill them, and that requires electricity. If no power is provided, the capacitor discharges and it all becomes 0s. This is also a feature and not a bug. The ability to reset ram to all 0s under any situation solves issues when a computer is glitched. Imagine turning the computer off and on and it doesn't unglitch because its still running code off the same ram that was glitched since it wasn't wiped. Hard Drives use disks that are magnetised to store bits. SSDs use a little trick known as a floating gate mosfet which traps electricity (without being able to discharge over time like a capacitor), which stores bits without power."
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jwufyv | How do humidifiers work? | Technology | explainlikeimfive | {
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"Most of the cheap ones are just an ultrasonic speaker that causes waves and splashing. It's powerful and fast enough that it makes a fine mist. This mist quickly evaporates into the air to increase the humidity. Some use heat and just heat and boil the water to make steam."
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jwxpcm | How can people find a location just from the contents of a photo? | Technology | explainlikeimfive | {
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"4chan used a lot of techniques to find Shia's flag. More about it [here]( URL_0 ) They used star constellations as well as weather and flight data to get a rough estimate of where the camera was. Then some people went out with their cars to honk at precises times, allowing the camera to be triangulated by sound"
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jx07wo | What is the reason behind green screens being "green"? Can they be other colours as well? | Technology | explainlikeimfive | {
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"Yes, blue screens were used before digital film making became mainstream, technically any color would work too, but it’s better to use primary colors (red green and blue) because it’s easier to have to only look at one color channel, and red doesn’t work because our skin is mostly pink, which is just light red The reason we switched colors is because film works better with blue and digital cameras work better with green"
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jx7roo | How can a computer build up from the basic logic gates to complex programs and games? What is the connection between each layer? | Technology | explainlikeimfive | {
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"The philosophy is to gradually create more and more complex programs from simpler ones. We start with logic gates (although they aren't the first layer), using them you can compute simple mathematical operations like addition or multiplication. From now on, we use those operations, not single logic gates. You can write a simple program to draw a triangle on your screen. We can use this program to draw any object built of triangles, so basically any object (3D objects in games are usually made of triangles). This example is very simplified, but I hope you get the rule here.",
"This is definately too complex for ELi5. I should know, I took 4 years of exactly this in computer engineering. But... if I had to TL;DR it: Basic logic gates can be assembled into fundamental computer building blocks for rudimentary tasks: an adder, a multiplier, multi-byte AND, OR, XOR or things that read from a memory address. Each rudimentary task block can be wired so it is only triggered if certain electrical lines are fired. These electrical lines correspond with fundamental chip \"commands\". So now you have a library of fundamental commands. Lets use ADD as an example. Its been a while since I've done assembly language (this is what we're talking about now), but an ADD command would be like: ADD EX BX where the ADD command has access to registers EX and BX and will always deposit the result into some known other register.. for our example, lets assume ADD puts the result back into BX. All a register is a chunk of logic gates that holds a single byte of information. COmmands like ADD would be able to read and set values in some/all of the registers in the chip. So lets get a slightly better example. MOV EX 01011101 MOV BX 10010010 ADD EX BX This takes the number 93 and stores it in register EX, the number 146 and stores it in BX and adds the two together. To use the value, we know ADD dumps the results back into BX, so all I have to do is use BX. Each of these commands - in conjunction with the named registers directly maps to the signal lines that turn on the ADD logic gates and connect the bits in the two registers to the logic gates in the ADD block. So each command is itself simply a pattern of bits. Maybe on a purely electronic level, the MOV EX 01011101 command looks like 3 bytes: MOV EX 01011101 01111011 00000110 01011101 The first \"byte\" of this instructure selects what part of the logic (MOV) to fire up, the next byte somehow connects up register EX and the 3rd byte is the data value to stick in there. So now we're at the assembly language level. From there, higher languages like i=i+2 if i > 4 then jump to FOO can simply be expressed as equivalent assembly instructions: (lets assume EX holds the current value of i) ADD EX 00000010 (binary for 2) ; add two to i in EX MOV BX 00000100 (binary for 4) ; store \"4\" in bx CMP EX BX ; compare EX and BX JMP FOO ; if comparison is true, go to FOO; if false, just go onto to the next line here Translation of the higher language into assembly language is the job of a compiler. And all higher or even interpreted languages can be parsed and interpreted (have to be in fact) down to assembly language which drives actual logic gates in the silicon."
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jxciqu | How did the typing keyboard layout come about? | Technology | explainlikeimfive | {
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"Due to the physical limitations of a mechanical type writer. For fast typers, the physical arms that would extend outward to type a letter would get intertwined with another arm if those two letters were both very close together as well as typed in quick succession. The solution was to create a keyboard layout that would have common sets of letters be separated on the keyboard to reduce the risk of the arms getting intertwined. Because everyone was used to the layout by the time keyboards came out, it kinda just stuck around.",
"Theres an urban legend that says that the qwerty layout was first designed for typewriters to prevent the machine from jamming. Supposedly, if you typed too fast on a typewriter with it's alphabetical key layout, it was prone to jamming. The qwerty layout supposedly was much less likely to jam at high speeds. When computer keyboards were designed, they just stuck with what was, at the time, the most popular typewriter layout, QWERTY. Admittedly, this is just a story told to me by my first year computer science professor. I personally don't know how much of it is true. Neat story though.",
"Old type writers had mechanical levers between the letter keys and the stamp and put the letters on the paper. If adjacent levers were activated too close to each other, they'd jam up, drastically reducing the speed a typist could type. Christopher Sholes spent a long time playing with keyboard arrangements to minimize the chances of adjacent keys being pressed in succession. The QWERTY keyboard wr know today is the result. It has no purpose now other than tradition. There are many arrangements in existence, but QWERTY remains the dominant one because everyone is used to it."
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jxkk65 | Why do we have to pay companies for data? Isn't there an unlimited amount of "data" out there to use? Can it run out? | Edit: Thanks for the answers everyone. Seems its mostly just greed that answers the question. But there are also good points towards it. :) Stay safe and healthy. | Technology | explainlikeimfive | {
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"Maintenance on the infrastructure used to deliver data costs something. Constructing new wires and cell towers costs something. It's not entirely unlike paying your water bill. We're reusing the actual water and it won't run out in any way that matters, but the delivery system doesn't just happen.",
"There are a few misconceptions here to clear up. The first misconception is that you pay your internet service provider or cell service provider for data. What you're actually paying them for is to *transfer* data that you're getting from somebody else. Let's say, for example, that you load the Reddit website. Reddit is producing the data that comprises the Reddit home page. What you're paying your service provider for is the cost of getting that data from Reddit and then transferring that data from Reddit to your computer. It's kind of analogous to renting a moving van - the moving van company doesn't have any stuff to put in the van; they're assuming you've already got stuff to put in the van or you wouldn't be renting it in the first place! The second misconception is that you pay for a *quantity* of data. What you're actually paying for is a *rate* of data. For example, if you pay for 100 Mbps (that's \"megabits per second\") service, then you're paying for the ability to transfer 100 megabits of data every second. It would be like renting a moving van that you can drive back and forth between two buildings - you can keep transferring stuff by driving back and forth as long as you rent the van. Now let's get to the heart of your question - why does it cost money? Just as in the moving van analogy, the stuff *inside* the van - the data - isn't what costs money. Instead, what costs money is the infrastructure needed to transfer it. In the case of internet service, that's a big network of expensive hardware like routers and fiber optic cables, which all costs money to install, maintain, run (e.g., power with electricity), and upgrade. You and all of the internet service provider's other customers are basically collectively paying the costs of installing, maintaining, running, and upgrading that equipment. Again, the moving van analogy works well here. EDIT: Some have asked about monthly caps (e.g., you can only download up to 100GB per month). The short answer is that this is still a rate! 100GB/month. There's a long answer, too, if you're curious. Imagine that you're an ISP, and you have 1000 customers who each pay for 100 Mbps service. If they all use their internet service at maximum capacity at the same time, your network will need to be able to handle 1000 x 100 Mbps = 100 Gbps of data transfer. However, it's pretty unlikely that all of your customers will ever be downloading at maximum capacity at the same time. Let's say that you estimate that it's rare that more than 100 of your customers will ever be downloading at maximum capacity at any one time. Thus, if you build your network to handle 100 x 100 Mbps = 10 Gbps, that will be sufficient to handle all of your customers' traffic needs *most of the time*. You'll still occasionally get unlucky - more than 100 of your customers will do this at once, and their service will be shitty. Figuring out how much you want to pay for infrastructure vs how frequently you're willing to give your customers a shitty experience is a business tradeoff you have to make. If you want to dig into this more, this technique is called *statistical multiplexing*. By introducing monthly data caps, you limit the amount of time that any given customer can be downloading at maximum capacity. This, in turn, means that you can get away with a network that has lower total capacity and still deliver your customers a good experience most of the time.",
"You’re paying for the upkeep of the infrastructure across which the data travels, and to allow additional equipment to be purchased to support an increased amount of utilization. Having tiered pricing structures for different amounts of data (data caps) is (I think) done very arbitrarily and there is no real reason to charge more based on total amount of data. It “made sense” to charge customers using a metered approach because people are accustomed to that with other utilities. And companies like AOL, Prodigy, and Compuserve (when you used your phone line and a modem to dial in) charged more based on your usage because you had to dial into their servers, effectively taking a spot that another customer could be using and using a real amount of physical server resources of theirs. They charged based on time connected, not the amount of data transferred - though maybe they also had tiers based on data usage - and that made sense because you were physically connecting to one of their servers. AOL was notoriously bad about charging ridiculous amounts when you started going over your monthly minutes. ISPs wanted that same kind of money, and people went along with it for a while until collectively people understood more about the technologies. The answer to your question is simply greed, of course. :) Think of the data as the voices on a phone call. Your body is the server which “stores” your voice and from which it is transmitted, the phone company does not have any involvement with the upkeep of your body. They only handle the phone lines that your voice is transmitted along. Asking about if there is an unlimited amount of “voices” doesn’t make any sense, and the phone companies don’t incur extra costs if you speak more when you make a phone call. They only handle the medium along which the voices travel. They are concerned with maintaining their phone lines and adding additional lines to support more customers. The lines can handle up to some amount of concurrent phone calls simultaneously but there is no limit to how much you talk once you’re connected to someone. You can also think of concurrent phone calls as allowing higher speeds, so maybe for me to have 100Gbps download speeds, it requires the equivalent of 100 simultaneous phone calls. So the speed of your internet absolutely requires more resources, but once you have those “phone lines” in place to handle that speed, it doesn’t make any difference how many bytes of data are “spoken” on those phone calls. I’m mixing up the metaphors a bit but it was fun thinking and writing about it this way. edit- when I say “how much you talk once you’re connected to someone” in that last part, I didn’t mean length of the phone call. I meant if there are gaps of silence in your phone call or if you were to scream nonstop for the duration of the call (a lot of silence during a 5 minute phone call could be equivalent to 5 megabytes of data, whereas nonstop screaming during the same length call might be 20 megabytes of data, either way, the phone lines themselves are not burdened additionally because there is less silence on a call)",
"Internet is just an interconnection of computers, mobiles, devices etc. On a larger scale you can think of internet as interconnections of interconnections. Now, if we stick to the above definition, we need some kind of medium to connect different devices. The easiest one that we can think of is wires, radio frequencies etc. Let's talk about wires, one just has to connect two PCs with some wire + some secure mechanism, and boom u would have an internet of two PCs. Where \"data\" equivalents to transfer of information between them. Now imagine, you implement the above, ask yourselves a question are you really paying for the \"data\", nope!. You are paying for the wire + that secure mechanism. Now your next question might be, \"why do I have to pay a monthly fee?\", it's for the maintenance and for keeping all the helping systems up ( electricity charges, cooling charges etc ) \"Why do we have data - caps?\", partly cause of network congestion, sometimes the infrastructure could not handle stuff, and partly cause of business ( more the data limit the more money for the company! Since you have to pay more ) \"Bandwidths and speed?\", these both require money, the quality of wires used, hardware used etc \"Can it run out?\", if we again refer to the above example, we know that it's just like connecting a few computers together. So theres no question of running out unless the wires are cut or the secure connecting mechanism dies."
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jxnr2s | why will a USB to aux converter make the audio sound bad but a similar priced USB-C to aux or even lightning to aux sound like its coming straight from the aux port | Technology | explainlikeimfive | {
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"Because your USB to aux converter is bad? I dunno. There are many that do just fine. There's many USB DACs that will improve your output.",
"Because your USB-A to aux converter is probably cheaper and/or older than the other 2. Nothing inherent to the technology, but more to the target market. USB-A use is declining while C is increasing, therefore the latter tend to be newer and are able to be sold for more, enabling the use of better parts."
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jxnt5q | Why are bullet sizes usually in decimal and not just a whole number? | For example, why 5.56mm and not just 6mm? Why 7.62mm instead of just 8? | Technology | explainlikeimfive | {
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"Because bullets are designed with very specific performance parameters in mind. In the case of the 5.56 NATO they were: * .22 Caliber * Bullet exceeding supersonic speed at 500 yards * Rifle weight of 6 lb * Magazine capacity of 20 rounds * Select fire for both semi-automatic and fully automatic use * Penetration of US steel helmet through one side at 500 yards * Penetration of .135-inch steel plate at 500 yards * Accuracy and ballistics equal to M2 ball ammunition (.30-06 Springfield) out to 500 yards * Wounding ability equal to M1 Carbine On top of all that, they wanted a round with less recoil than the M2. After development and testing of many different new ammunitions, the brand new .223 remington was the round that had the best results for the specified parameters. It was later officially adopted by the US military and renamed \"Cartridge, 5.56mm Ball, M193.\" This round was further developed and became the 5.56×45mm NATO with the subsequent military designation of SS109 in NATO and M855 in the U.S. While 5.56 may sound arbitrary, it was the result of a 13 year project that spanned multiple countries and involved every major gun and ammunition company of the time, to create a small caliber, high velocity firearm for military use.",
"The 5.56mm NATO cartridge was in fact designed using the metric system. The bullet ended up as exactly 5.70mm in diameter, or in imperial it would be .224\". The designation of 5.56mm is from the diameter of the barrel which is smaller then the bullet in order to create an airtight seal around the bullet and allow the rifling to cut into the bullet. 7.62mm is exactly .30\" which were the caliber for the earlier rifles that these cartridges are based on. And even though most .30\" rifles are bigger, some are even over 8mm they were all called 30 caliber which were converted to 7.62mm. It should also be noted that some countries did call these 8mm instead of 30 caliber, for example the 8mm Label and the 8mm Mauser from the French and German manufacturing respectively. However these did not stick around. On the other hand the 9mm Parabellum round have kept its name until today.",
"To add to what others have said, the bullets weren't designed around nice round numbers because a) they weren't necessarily designed with modern units and b) they were almost all designed for military contracts, to be as cheap as possible while still being effective. So while making them slightly bigger to get a nice round number might seem attractive, a government that's buying ten million bullets isn't going to want to pay for that extra material. Add this to the various ways scaling up or down can affect projectile performance and you can see why that sort of thing was never taken into consideration.",
"Because they're often based on commonly used Imperial bullet sizes. 5.56mm is approximately 0.22\", for instance, while 7.62mm is 0.3\".",
"The real ELI5 answer is that they that the sizes were either based on old imperial measurements (which are unlikely to translate to round metric numbers) or were calculated to be the ideal size (which is unlikely to be a round number for anything). Performance/efficiency is far more important than having a number that's easier to write down.",
"Because the bullets are 5.56mm and not 6mm? It's a measurement.. not a random number? Or do you mean \"why don't they just manufacture 6mm bullets instead of 5.56mm?\"",
"Ballistics can change drastically as the size, shape, weight, powder charge, etc change. There are both 6mm and 8mm cartridges, and they perform differently than 5.56mm. New cartridges are generally designed around ballistic parameters, and the end result uses whichever bullet size and case dimensions meets that need. Sometimes it's an existing bullet and sometimes an entirely new bullet is engineered. Historically the caliber size started as a decimal of an inch, which makes sense, and we've just stuck with it. .50 for example is a half inch diameter bullet. It has gotten a bit convoluted over the years, as others have pointed out with the .357 and .38 special using the same bullet and .223 using a .224 bullet for example. Don't get me started on .30 bullets. There's a lot of them.",
"In Engineering and Science, precision is important. The more decimal digits are specified, the tighter the tolerance must be when manufacturing., plus or minus half the lowest digit. So whether 5.56mm or 6.00mm, but never 6mm. A 6mm would be 5.5mm to 6.5mm A 6.0mm would be 5.95mm to 6.05mm A 6.00mm would be 5.995 to 6.005mm And that sort of precision is required to keep the bullet the right size for the barrel.",
"Paul Harrell has a great video on YouTube going into great detail about different caliber origins. If you like firearms, he's awesome. [Here's the video if you're curious.]( URL_0 )",
"There's a story behind every round. .30 Caliber rifle rounds were standard for many years. In metric, that's 7.62mm. Quite simply, it's a standard sized round that's converted to a different unit. 5.56x45mm NATO was created to meet the CONARC parameters. They built a round to meet parameters and it just so happened to come out that size. Remington was making the .222, Springfield made the .224 based on their design. Remington's .222 underperformed, so they made a \".222 special\" with a bigger case. It's common in the ammunition world to give hotter loads a bigger number, so they re-named it a .223 (despite it actually being a .224 projectile). Converting the .223cal to metric, we get 5.56mm. There's plenty of \"round number\" bullet sizes, 9mm is one of the most popular in the world for instance. .30 cal, .40 cal, .50 cal, 10mm, and 13mm are pretty common as well."
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jxob5s | What is the difference between automatic and autonomous driving? | I know that automatic driving is often linked to beacon signals etc. But e.g. the drawn lines along a street where an autonomous care drives, are visual beacons, too. So why do we make a difference between automatic and autonomous driving? Or what defines that difference? | Technology | explainlikeimfive | {
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"There is no super strict definition and anyone can use any word they want but generally automatic driving is more general a car in the 1950s that was following a buried wire would be an automatic car, an autonomous car is generally using machine vision and AI to drive on it's own. But like, the police won't come and arrest you if you use either word either way."
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jxpugy | Why do SSDs have limited amount of rewrites? | Why do SSDs have a limit rewrites whereas from what I recall, HDs didn't have this concern? (though they broke often haha) SSD's have no moving parts, so I'm curious, is it just the current that damages it over time? What happens exactly? | Technology | explainlikeimfive | {
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"HDDs work by rearranging some particles using a magnet. You can do that more or less infinite times (at least reasonably more than what it takes for the mechanical parts to wear down to nothing). SSDs work by forcibly injecting and sucking out electrons into a tiny, otherwise insulating box where they stay, their presence or absence representing the state of that memory cell. The level of excess electrons in the box controls the ability of current to flow through an associated wire. The sucking out part is not 100% effective and a few electrons stay in. Constant rewrite cycles also gradually damage the insulator that electrons get smushed through, so it can't quite hold onto the charge when it's filled. This combines to make the difference between empty and full states harder and harder to discern as time goes by.",
"Before anyone starts to get anxious about their SSD dying, don't worry. An SSD is expected to survive between 10-15 years of common use before being unusable Source = > URL_0",
"The failure mechanism for HDD was more of a wearout of the motor or bearings and less of a wear out of the platter itself because it was just changing the magnetic field of particles. SSDs use flash with a \"floating gate transistor\" and we store values by injecting charge onto that floating gate. But how do you get charge onto a floating gate? You use enough voltage to punch the electrons through the insulators that keep it floating Each write cycle damages the insulator a little bit causing it to break down over time until the electrons on the gate are free to escape so you can't reliably store bits on it. For most SSDs though lifetime isn't a huge concern, you can write about 1 PB of data onto a modern 1 TB SSD before it starts wearing out. SSDs are also built with spare blocks that it doesn't show you, so your 1 TB SSD may come with 1.2 TB of flash and it'll rotate that extra 0.2 TB in as existing blocks get too many writes on them to extend the life of the drive as a whole.",
"They do have moving parts. Just on a microscopic scale. When you store data on an SSD a current is passed through a semiconductor layer, causing electrons to move. Shifting around these electrons into different positions is essentially what allows you to store data. Now in pretty much every SSD on the market multiple states are stored in every memory cell, which greatly increases the capacity/volume. Generally a modern SSD will have TLC (that is triple layer cells) and store 3 bits for every single memory cell. The problem is that every time you write to a cell on an SSD the semiconductor layer wears out slightly, causing electrons to essentially become stuck. To remedy this, you can just apply a higher voltage, but at some point the additional voltage required to store a certain state in a cell becomes so high, it will start overlapping into the voltage required to store the next state up. This means the two states would no longer be differentiable and the cell is effectively dead. Because the more layers you store per cell, the narrower these margins are, the higher layer cells you use the less write endurance you get.",
"How do you know when your ssd is getting close to end of life?"
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jxt90g | What is 'vote fuzzing' and how does it apparently help 'stop spam?' | What is 'vote fuzzing,' and how does it ['stop spam?']( URL_0 ) And while we're at it, why is it that scores on old or archived posts change rapidly when I refresh the page? | Technology | explainlikeimfive | {
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"The first instinct with spam bots is to ban them. But if you ban them, they'll just come back on a different account. So instead you \"shadow\" ban them. They can log in and comment and vote, but no one ever sees it. They *think* they are posting/making comments/voting but actually aren't. Probably with this is you can easily check to see if you are shadow banned by voting, then refreshing and checking the vote count. If it didn't change, then your vote didn't count and you are shadow banned. Instead you allow the shadow banned bot to vote, but then reddit automatically makes a vote in the opposite direction so the net vote count doesn't change. That's part one of the fuzzing. The second part of the fuzzing is to randomly adding up/down votes at random intervals so a bot can't tell if its vote was countered by reddit or if it was just reddit fuzzing the vote at random.",
"Vote fuzzing is when the vote of a post or comment is more or less right, but not exactly right. So a comment that has a total score of 35 might show anywhere between 32 and 38 - it is pretty close, but not 100% accurate. It helps reduce spam because it means that accounts that have been shadowbanned by the admins have a harder time realizing it. Shadowbanned accounts can still vote, but their votes aren't counted in the total points for a post/comment (many spam accounts are used to artificially upvote other posts/comments which are themselves spam or people who paid for upvotes). If votes were 100% accurate, the bot would be able to see that its vote was not counted, but the fuzzing makes it more difficult for the bot to know that it's specific vote wasn't counted."
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jxtp9h | How can 1tb of data fit on physically same sized micro sd 16g card? | Technology | explainlikeimfive | {
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"SD is just a packaging/socket standard, like USB or M.2. The manufacturer can put whatever size IC inside the package that they want (within the constraints of the size of the package itself and manufacturing technology, obviously). I'm not familiar with the process but I'd imagine that a 1TB micro would have to be using at least a 7nm process to fit that many cells in that amount of space."
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jxvc5r | How do TVs work? | Technology | explainlikeimfive | {
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"Television is really a three-part invention: the TV camera that turns a picture and sound into a signal; the TV transmitter that sends the signal through the air; and the TV receiver (the TV set in your home) that captures the signal and turns it back into picture and sound. TV creates moving pictures by repeatedly capturing still pictures and presenting these frames to your eyes so quickly that they seem to be moving. Think of TV as an electronic flick-book. The images are flickering on the screen so fast that they fuse together in your brain to make a moving picture (really, though they're really lots of still pictures displayed one after another). If you have cable television, your TV pictures are \"piped\" into your home down a fiber-optic cable laid beneath your street. If you have satellite television, the picture you see has been bounced into space and back to help it travel from one side of the country to the other."
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jxxnz9 | Why does turning off Hardware Acceleration allow me to stream Netflix, Hulu, etc over Discord and Zoom? | I can't figure it out for the life of me. I just know that it works. | Technology | explainlikeimfive | {
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"When you're doing hardware acceleration, you're doing things like passing the video stream directly to the video card and the video card has specialized hardware that can decode and decompress the video and write it directly to the screen. There's nowhere for discord or zoom to hook into the video stream to broadcast it. When you turn off hardware acceleration, the main CPU does the video decoding and the stores it in a memory buffer that eventually gets sent out out to the video card. This where Discord and zoom can hook into the buffer and relay the video."
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jy0lmn | How do bots work? Specifically the ones scalpers use to purchase new products like the PS5. | How do they get past CAPTCHAs and websites going down when a new product goes up? | Technology | explainlikeimfive | {
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"Just a web script. There's a bunch of ways to make them. Bash and curl if that's your thing. Or [start here for doing it in Python]( URL_0 ). > How do they get past CAPTCHAs That's a cat and mouse game that's constantly evolving. At worst they just buy some mechanical turks to solve capchas. > and websites going down when a new product goes up? They keep trying until they get in. The thing is, their scripts are trying 10,000 times for every human that's trying to get in the front door.",
"If the catchpa isn't on the final payment screen, which it never is, you can manually log in once and then launch your bot(s) by opening links \"in other tabs\". There are lots of ways to walk an exploit past a security barrier.",
"The ones I've seen can harvest cookies from the sites that use captcha before the release so when the item actually gets released it uses a cookie to bypass the need for a captcha as it's been validated before..... Or some kinda tech wizardry like that. Then as far as checking out items, they create 20+ tasks that all run at the same time. The bot uses specific keywords or item SKUs to constantly ping the site looking for updates. As soon as it detects that sku it'll usually have an automated check out based on what site or payment platform the site uses. Then it just spams the shit out of the site trying to check out until one or all of your tasks are succesful. I used to bot sneakers years back. It's honestly probably way more advanced now."
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jy331c | What determines if we get 4G cellular or LTE cellular on our phones? | Technology | explainlikeimfive | {
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"The hardware & software in your phone determines what it's capable of. The closest cell tower negotiates with your phone to use the best features they both support. This varies between towers, carriers, phones, service plans, network load and weather. LongTermEvolution and 4G are basically comparable and can be considered marketing terms. 4G was faster initially but the LTE spec kept evolving and caught up feature wise."
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jy493q | Why is the web CAPTCHA necessary? | What would happen if they all disappeared? | Technology | explainlikeimfive | {
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"To prevent web bots. It’s harder to code something to click submit web forms with a captcha.",
"Correct me in I’m wrong, but the web CAPTCHA is to prevent bots from flooding websites. For example if there is no captcha when signing in to your Facebook account, then a computer bot can try to break in by trying an endless amount of passwords. The captcha stops this from happening by asking the user to complete some kinda of task."
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jy7sic | How do they put coke and other fizzy drinks into cans and bottles without them bubbling up and losing their fizziness? | Technology | explainlikeimfive | {
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"Pressurized carbon dioxide (CO2) mixes very well with water. It mixes most efficiently with cold, but not freezing, water. They add highly pressurized CO2 to water to make soda water, this is usually done in large vats of cold water and they pipe in CO2 to get the mixture they want. Once they have the soda water, they then put syrup and everything else that goes into a soda into a bottle, add the soda water, and cap the bottle. Once you cap the bottle, you create an equilibrium (pressure is equal between the air and the liquid) and you have a nice, refreshing and fizzy drink whenever you want.",
"So the chemical responsible for the “fizz” is CO2. this chem forms into an equilibrium as it forms CO2 and carboxylic acid. This equation is a function of volume of water and pressure of gas. The less water and more gas, than the more acid is formed. So effectively as water is constant, so long as the pressure is maintained before you open the can, the carbonation is constant. That in mind if there is a can the acid CO2 forms can react and eat through the lining and loose the CO2 content. Remember that the CO2 and carboxylic acid is one and the same chemically speaking in lay mans terms."
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jycpa3 | Why there's almost no UPC on li-ion? | We had electronics and power tools on li-ion power widely available for two decades now, yet UPS remain on lead acid in 2020? Why? | Technology | explainlikeimfive | {
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"You can totally get UPS systems based on Li-Ion if you so choose, but the main reason most remain on lead-acid is because of cost--that many lead-acid batteries are cheaper than the equivalent Li-Ions, and the circuitry to handle charging them is considerably less complex as well. Given the main advantage of Li-Ion is they're smaller and lighter for the same energy storage, and UPS devices tend to be static installations where you're not too worried about the size and weight, there's not a huge benefit from using them in this role.",
"Lithium ion batteries are much more expensive then lead acid batteries. Last time I checked the price including delivery it would be twice as expensive. In addition there are several issues and unknowns related to storing lithium ion batteries fully charged unattended for years at a time. We have far more experience with lead acid batteries in these conditions and have resolved almost all issues with this. So when weight and volume is not a huge issue such as in a UPS or off the grid house then lead acid batteries are still preferred."
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jygrze | how do you use a bidet? I've never seen one in real life, tho I get the concept. | Technology | explainlikeimfive | {
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"A high quality one (think Toto brand) will have a pressure-activated switch under the seat that sprays the bowl with a mist to keep it clean before use, and then variable streams with variable water pressure and angle of trajectory. Generally there will be a stream oriented from the front of the bowl towards the back for females, and a stream from the back to the front for both genders. Then, a fan can be activated to dry, but unless there is a front fan it will be useless for the front to back facing stream. So, generally that area would still need to be pat dry depending on just how dry you want to be. Also, higher end bidets will have warmed seats, water, and air all with variable temperatures. All this can be activated from a remote mounted to the wall, so the whole experience can be very germ free.",
"It's a jet of water - quite powerful. Source: Squirted myself straight in the face seeing how one worked, once",
"Stream of water that washes off the big chunks. Then, you wipe a few times to dry off/get the rest of the poop out. I have one that attaches to your toilet. It was like $30 on Amazon and I love it.",
"Not like a drinking fountain, a dish-sprayer would be more like it. Except a smaller, *somewhat* more forceful spray. Perfectly comfortable. So, it's like giving your nether regions their own, appropriately sized, shower. So, are you still wet? Unless your bidet incorporates a blower (like mine!), yeah. But you're clean, so, you take one of your dedicated bidet-towels and blot. Short version - they're great. Do it.",
"This is what I usually do, We have a [handheld one]( URL_0 ), I grab the gun, point it at the right direction, keep the water flowing at the desired pressure until am satisfied, drip dry, use a couple of TP squares to dry.",
"Yes, it's a jet of water, not too strong, just a nice spray. Many have settings so you can adjust the level of spray to your comfort. Some have directional settings, so if you're female you could use the one that doesn't send fecal matter forward (potentially causing urinary tract infections). You use it for a few seconds to get clean, then pat dry with a very small amount of paper instead of having to use big wads of paper. You could even drip dry if you have time to sit there and scroll through reddit for a couple minutes. You can buy the ones with a heated water supply, but they're expensive. You can make do just fine with the $40-$80 models on amazon that use cold water. You get used to it very quickly, it's actually refreshing, and the water line is gonna be room temperature anyway, so nothing to worry about. There are two big problems with tp. The first is that you have to use so much of it---you don't realize how much you use until it's scarce, and then you watch with alarm as your supply dwindles by the hour. The second problem with tp, much worse than the first, is that it doesn't really get you clean. You wipe and you wipe and you wipe, but there's always going to be at least some residue, and then it's gross that you're walking around all day with an itchy smelly butt, or that it's dried up and you're walking around with your underwear full of crusties. Disgusting. Think of it this way: imagine you tripped and fell face-first into a big pile of fresh St. Bernard-sized dog shit. How much dry toilet paper would you need to clean off your face? If you scraped it all off, wiping over and over and over with only dry paper, at what point would you feel it was good enough that you'd let your SO kiss you on the cheek? The answer is never. You wouldn't be happy until you had cleaned your face with soap and water. Back to the bidet: plain water works OK, but if you want to be even cleaner, keep a softsoap dispenser near the toilet. Spray well, then apply some soap, then spray again to rinse. You'll feel as fresh as a baby's butt after a bath. Moral of the story: treat your asshole with the same care as you treat your face."
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jyldj9 | How do calculators know the answers? | How does a calculator get programmed or how does it always know the right answer? I’m assuming elves but I could be wrong. | Technology | explainlikeimfive | {
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"They're built up from a bunch of simple components called logic gates, which are these sort of conditional light-switch circuits which can output either a high or a low voltage, depending on whether their inputs are receiving a high or low voltage. There are a few kinds of logic gates, but the simplest ones people usually learn about when they're learning electronics, are the AND, OR, and NOT gates, which do pretty much exactly what their names suggest. An AND gate with 2 inputs, will output a high voltage only if both of its inputs are receiving a high voltage. An OR gate will output a high voltage if either one of the inputs are receiving a high voltage. A NOT gate has only 1 input and will output the opposite of whatever input it's receiving. By wiring up a bunch of these gates' inputs and outputs to each other in clever ways, you can get them to perform all kinds of functions. You can buy integrated microchips which have a bunch of these gates pre-wired up so that they can do arithmetic tasks like adding, subtracting, etc. Most cheap calculators are made using these chips. eta: if you're interested in the details of *how* gates can be put together to form arithmetic circuits, [here]( URL_0 ) is a brief explanation of one very common design pattern called an \"adder.\"",
"The calculator is a little computer. It does the calculations a lot like how you'd do them on paper (but in binary because it's a computer). And it does them a lot faster (because it's a computer). You know how they taught you in school? To add 1234 and 5678, you do 4+8 which is 12, so write down 2 and carry 1, do 3+7+1 which is 11, so write down 1 and carry 1... etc? The calculator does that (but in binary and at the speed of electronics)"
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jylfr2 | Sound in shows and movies, that goes from soft to loud and you have to keep changing the volume | Technology | explainlikeimfive | {
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"Audio for shows and movies isn't generally mixed for TV speakers. Movies especially. They're mixed initially for surround sound where dialog and main sounds get sent to a center channel, and effects and other noises come from other speakers around the room. If you watch a movie on a 5.1 surround sound system that's tuned for your room, you'll find you won't really deal with this issue anymore. When re-mixing for a home release, they don't know what setup you're going to have, so they do what they can, but generally if you're using normal TV speakers, there's some software somewhere in the chain that's down-mixing the audio to just two (very shitty) speakers and it isn't doing a very good job. They aren't taking the time to go through the movie another 40 times listening to everything and manually adjusting volumes for a 7.1 mix, a 5.1 mix, a 4.1 mix, a 2.1 mix, a 2.0 mix, and a mono mix. They're just clicking a button in software to output a mix, and letting your (crappy) hardware at home deal with the mix. There is also the fact that in many cases, audio engineers for a show are very rushed, and don't have time to give an ideal balance in volume to every channel before shipping the episode. If you have some cash and feel like solving the problem, a mediocre AVR, a center channel speaker, and a L and R speaker will solve your issue almost entirely. Some TVs also have software solutions that work okay, like volume normalization, or \"dynamic audio\" or something, but it will depend on the model of TV you have.",
"dig thru TV/receiver settings for “dynamic volume” (receivers) or “reduce loud sounds” (apple TV, LG TVs). it’s called compression but goes by many other names; on a Denon receiver it was called “night mode” (low/medium/high) so you can look for that too.",
"That specific thing isn't really an issue in the sense of being some kind of mistake. By and large, it's their intent or artistic vision or whatever you want to call it. If you set the volume so that the dialogue is at a comfortable level for you, then when there's gunfire or a car crash what you hear really is how loud they wanted the gunfire or car crash to be. I don't particularly like it either, especially in theaters where the sound systems are powerful enough to make the loud parts downright oppressive. But it's not a mistake or technical glitch; they're just making these movies for people who aren't you or me."
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jym7v7 | Why are domestic dishwashers so slow? | Technology | explainlikeimfive | {
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"Commercial dishwashers typically reach much higher temperatures than their residential equivalent, use a lot more water, and are a lot louder. All of those are acceptable tradeoffs when running a business, but you likely wouldn't want one in your own home, where it's not imperative that dishes are cleaned as quickly as possible.",
"They don't really do the same job. Commercial dishwashers basically rinse and sanitize the plates, but the plates go in pre-washed. There's also the fact that all the plates that go in have only been sitting for 30-60 minutes max. Domestic dishwashers often don't run every day, so they have to be able to deal with dried out food residues because the plates may have been used 3 days ago. That means the plates need enough time to soak, and there is no good way to speed this up. If you sent a 3 day old plate through a commercial dishwasher, it would come out dirty. One other difference is that a commercial unit stores pre-heated water or cleaning solution. This is a good idea for a machine that does load after load, but you can't really do that in a domestic setting where the dishwasher often sits unused for several days. So domestic units will use cold water and slowly heat it up inside the machine.",
"It's cheaper to be slow. It's like driving 100 km, it's cheaper to do it in 1 hour, rather than speeding and doing it in 40 min, or even renting an helicopter and doing it in 20 minutes. My mom thinks the quick cycle on the washing machine is more economical. No, your machine need to make extra efforts like reaching higher temperature, using more water, spinning faster. It's much cheaper to let soak but it takes more time. That's why economical cycles are the longer cycles."
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jyns4l | Where does the GPU come into bitcoin mining? | So to my understanding, its basically more or less a lottery that requires electricity? I still don't really understand how exactly it works but I'm more curious as to why it requires a strong GPU or in some cases multiple GPUs? How do the different high end GPUs contribute to bitcoin mining compared to lets say a low profile GPU? And also how does it use the GPU... is it similar to running a high demanding game or something along those lines? | Technology | explainlikeimfive | {
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"So, ignoring the question of \"what is a bitcoin?\" for now, the general idea is that \"discovering\" or \"mining\" a bitcoin is a very mathematically intense process. It involves trillions of calculations. And it just so happens that the *type* of calculations involved are similar to the calculations needed to display 3D graphics. So GPUs are uniquely positioned to be able to find bitcoins faster than any other type of consumer hardware. And yes, more powerful GPUs are faster at mining bitcoins.",
"GPUs are masters of parallelism. You feed it some code and tell it to run 64/128/256/512/1024... copies of the code at a time on different data."
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jyo14u | why phones die quicker in cold weather. | I left the house this morning (6am) with 100% battery life. I was outside all morning and used my phone very little but by 10am my battery life was at 37%. Why does my phone die so quickly when it's cold? (It was 28°F this morning) | Technology | explainlikeimfive | {
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"The short answer is that batteries rely on chemical reactions to work, and freezing temperatures slow or stop those reactions. ... In fact, cold temperatures prevent the kind of slow discharge battery ions do under room temperatures, as the engineering website URL_0 explains.Jan 4, 2018 Live Science › 61334-batteries-... Why Does Cold Weather Drain Your Phone Battery? | Live Science URL_1",
"As the temperature decreases, ion diffusion decreases, and conductivity increases. This means your battery is going to discharge quicker and output less usable power per movement of ion."
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jyp4gk | Why does every type of next gen console or graphics card sell out instantly upon release? | I see people every day posting about their graphics card that is like a lottery ticket to acquire one. Same with day one releases of next gen gaming consoles Could they produce enough of the product to meet demand prior to releasing it? That’s seems like poor business practice to me | Technology | explainlikeimfive | {
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"The companies know how to make the most profit. Storing unsold product in a warehouse until you have enough supply for every single customer would both cost money and potentially lose sales to a competitor releasing their product before you.",
"> Could they produce enough of the product to meet demand prior to releasing it? Technically, yes. Would you be happy if you wanted a PS5, knew that they were finished and rolling out of factories, but couldn't buy one until March? That would be a good way to piss off their entire customer base. Or, they could spend hundreds of millions of dollars outfitting extra factories for the initial release, and then shut half of them down after a few months when the initial demand was met. And that would be a terrible financial decision.",
"Another factor here - covid has not only messed with supply chains, but increased demand. People who would normally not care as much are relegated to playing videogames."
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jyph3g | What is it that makes Toyotas so reliable even after many years of use? | Large amounts of spare parts made? Manufacturing process? Design differences? | Technology | explainlikeimfive | {
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"Toyota revolutionized a manufacturing process about 40 years ago that allowed bottom up refinements to address manufacturing issues (the assembly guys on the line can spot an issue and report it up the hierarchy to get it changed, rather than waiting for the managers and engineers to discover issue) and had an extreme focus on quality. At this point, other car makers have caught up in many respects and it’s more reputation than anything at this point. And the worst brands today are still better than the best a generation ago in terms of reliability.",
"One of the foundations of Toyota's incremental production improvement processes is called \"kaizen\". [Here's a truly excellent 6-minute YouTube video documenting how Toyota applied it's kaizen improvements to help speed up service at a New York City Food Bank.]( URL_0 ) I thought this was a really neat way for a big company like Toyota to donate that which it is truly the master of (process optimization) and make a long-term, fundamental improvement to this food bank, rather than just hand out a one-time cash donation.",
"I was lucky enough to visit Toyota in Japan, it is insane, its a whole city, Toyota city. I'm not the biggest fan of Toyota but after visiting a couple museums and a factory tour, I came out with an I credible respect and appreciation. The assembly lines were incredibly clean and efficient despite regular groups of distracting tourists. The museum had incredible detail, I could easily have spent half a week learning. It started from the VERY beginning, how they originally make textiles from cotton. The old equipment and factories. it was a functional museum they did regular demos of various processes, they had a full size stamp that they used to shape a door panel, it was like 3 stories. They showed various innovations and steps for every car part from the headlight to different engines. I could go on but if thats the kind of work and dedication that goes into just their museum, it doesn't surprise me the quality of cars they make. If you ever get the chance, I would highly recommend visiting.",
"Having taken apart and rebuilt my 2000 Toyota Tacoma I can say that the engine was designed to be fixed. The sizes of all the hardware is very consistent and it all fits together in a simple way.",
"One thing Japanese brands like Toyota tend to be very good at is ensuring that the parts of their cars that are most likely to break with wear/age are designed to be replaced and manufactured inexpensively. These parts also tend to be ones that don't damage other components of the car immediately when they fail. It keeps maintenance costs down, so more cars stay on the road. This increases demand for replacements parts, so they stay cheap. If a car is cheap to maintain, people are less likely to skip repairs or adopt a \"I'll just drive it until it dies\" mentality. It's a self-reinforcing cycle. They're not necessarily that much less likely to break than other brands (i.e., they aren't \"invincible\" like people tend to say).",
"In short, Japanese engineering. There's a lot to be said for company loyalty and the idea that one does a good job to honour oneself and the company. There are a few American companies (Zippo for example) driven by pride in their design who'll offer a lifetime guarantee on their products, but mostly you'll find employees just doing whatever they need to do to get by and make a product that will sell and survive just long enough for the new model to be ready.",
"> Manufacturing process? Design differences TL;DR: These. Specifically, how they approach designing the vehicle and it's components, and the requirements for manufacturing the parts. They design a vehicle that's as basic as they can get away with. Many non-luxury Japanese vehicles don't have some bells and whistles that other manufacturers add, and they make the same designs for years, refining it as they go (other companies do this too, I can think of a Ford V6 that's had variations put in the Ranger, Explorer, and Mustang for years). Then the parts are manufactured to tighter tolerances than other manufacturers bother with. Toyota recently teamed up with BMW on a sports car, and reportedly BMW people were shocked by the high quality assurance Toyota's people insisted on. This isn't an absolute. There are a couple Japanese brands that don't quite have the reputation Toyota or Honda do. There are a couple European brands that have reputations for being quite reliable, contrasting other Euro nameplates. You can find extremely reliable examples of any brands vehicles, and you can find lemon Hondas. Heck they had an issue with a certain CRV engines and cold starts/short trips recently. Luckily most modern cars are very reliable compared to even twenty years ago, and cars of the 2000's and 2010's were much better than cars of the 1980's (which is partly why the used car market is so strong right now). Takeaway message for buyers: do a little research and decide if you can live with the possibility of one or more of the common issues (they all seem to have *something*), the car you're interested in might develop, on the slim chance it develops a problem at all. *Edit:* please forgive typos, am on mobile and am tired.",
"I work for Toyota, be it the material handling part but still a lot in commin. When we hear that a machine has issues we send techniciens to the client and they do a full diagnose on the machine. Even if it is just a loose wire for example it gets the full diagnise. All this data is then processed to see what has caused the problem and then the designers try to implement changes to avoid this issue in the future",
"When they make cars together with BMW Toyota note that while BMW test the assembled car quite extensively, BMWs were equally surprise at the level of testing down to component level. \"...BMW couldn’t believe how extensive some of our quality and efficiency studies were as parts came into shape one by one. We would take every bit down to a fastener or rivet, and put it through our stringent quality control and a dozen other testing, we’d ship thousands of parts back to Japan for analysis. That is normal to us. Each piece we test at our level, they were now the ones surprised.\"",
"My brother in law is a paint specialist at Toyota manufacturing in TX and I can tell you from listening to him for the years he’s been working there that their attention to detail is unlike anyone else. Kaizen, and other things mentioned here are spot on. He spent a couple years in Japan on rotational assignment and the processes there are the same as they are in TX. So, I’d say consistency in management, and continuity in production, are also contributing factors to Toyota quality. Fun bit: he was given millions of dollars to reduce the overspray (ie waste) in one of the paint processes, and he succeeding in doing so. So, consider the savings over time by reducing overspray by, say, 8% when you’re rolling a new vehicle off the line every 60 seconds or so (not sure of the exact “takt time” at present).",
"No one seems to mention lack of innovation. Look at the Tundra. Every other truck manufacturer is refreshing their trucks every few years. The Tundra? Hasn’t been refreshed in 14 years. They still use the same engine as 11 years ago. The transmission is the same one they used 14 years ago. Have you been in a new Toyota? It’s like driving a car from 2010. It’s surreal. Get in a top of the line RAV4 and notice how stiff the seats are, how boring the interior is, how behind the times the technology is. But all of that is part of quality. Sure, the new Rams are impressive, but all that new shit breaks because it hasn’t been perfected. Meanwhile, the Toyotas that are running the same platform as 10 years ago will last a million miles. There’s a lot of factors, but no one seems to mention this one. As a Toyota fan who has switched to Mazda, figured I’d mention it.",
"Beyond their production processes that everyone mentioned. The Japanese take fucking PRIDE in their work. I'm sure there's a million corners an American company would cut to cut costs, but the Japanese care about selling a reliable product. Hondas, Toyotas, and Yamaha fucking jet skis. Yamaha \"turbojet\" jetskis have identical engine bays from the late 90s to 2019. They found what worked, they made a few larger engines, but they stuck with what worked. No need to change it drastically every 2 years to up the price; just a fun, reliable machine. I fucking love the Japanese",
"W. Edward Deming, an american, helped their success immensely. Variation is the nemesis of quality. Via utilization of SPC (statistical process control) they monitored key points for variation using various data gathering methods such as x bar and r charts, and if parts started getting out of spec. they could make corrections immediately rather than discover the problem after 50 parts slipped out. That is why they are better quality cars, because they monitor variation in the parts they make, very closely.",
"Decent manufacturing practices + Kaizen (2 second lean here in the US) = an affordable car that lasts longer than other competitors at that price point. Kaizen principles are excellent if leveraged effectively. Usually they’re hackneyed attempts by corporate overlords to maximize profits, which isn’t the point of Kaizen.",
"Toyota builds reliable cars based on Japanese technology and innovation. However, same can be said for Mercedes as we often have in Europe Mercs with over 1 million km driven on one engine and they still run perfectly.",
"One specific thing is the position of the fuel injectors. Gasoline is a solvent which is really good at cleaning surfaces like the inside of engines. This is great because carbon deposits build up inside of engines and gasoline can clean those parts so deposits don't develop. Toyota fuel injectors are positioned in a way that is conducive to cleaning the piston valves while most fuel injectors are only focused on fueling the vehicle.",
"Let me give an example. Volkswagen built a van named LT type 2 back in late 90's and early 2000's. It had a forged engine block and could see a million kilometers with ease. It did not give critical faults or the engine didn't blow up easily. That meant no gain from the engine repairs. They stopped the production of LT and produced the new beautiful Crafter with aluminum engine blocks. Guess what, their blocks started cracking on every 500 or 600k kilometers. This might just be a conspiracy theory against VW, but seeing the professional drivers complaining with my very own eyes proved somehow right those theories. That's where Japanese cars show themselves. Not only Toyota is that reliable, Nissan, Subaru, Mitsubishi and other variants are also quite reliable brands.",
"Adding to other answers, one big thing is the contrast in quality. Chrysler is synonymous in the United States with low quality. Toyota is the opposite. Some tin foil hat theories I've heard which I kinda sorta believe is that American car companies are catering more to the rental and lease industries. Make a car that will last well until 60k miles or so. Right after the rental companies sell the car or people return their leases. Economically it makes a ton of sense. You sell more cars this way. For a owners perspective it sucks. Many people buy cars with the intent of using it until the car dies or have reason to upgrade. These people buy cars maybe once a decade and on top of that, they tend to buy used. So that's why you see resell value on quality cars to be so much higher on brands like Honda and Toyota versus Nissan and Chrysler.",
"It's partly because Toyota is proud of their \"most reliable vehicle\" title and provide free service for new vehicles. I take mine in every few months for a ToyotaCare inspection and don't pay a dime."
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jyt7wm | . If someone needs to take an MRI scan but has metal implants in them, how do they go about doing the scan? | Technology | explainlikeimfive | {
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"Most implants are titanium or ceramic nowadays. Medical equipment manufacturers have been intentionally marketing implants as “MRI safe”, because of how important MRIs are to modern medicine. Older implants or those not rated for MRI safety make you ineligible to get an MRI, as it would likely kill or injure you to even enter the room with the machine. In those cases, CAT or PET scans are used.",
"You check exactly which implant it is first. Then if you can't do it you don't do the MRI scan. About that one House episode where some inmate had prison tattoos with lead ink- they just get very warm and hurt.",
"I think most metal implants are made of titanium or stainless steel, both of which are non magnetic.",
"The metal supports in my femur, knee, and hip are all titanium. I've been assured that if I need an MRI I will be fine. Sadly I have to take their word for it. Guess we'll find out.",
"Most implants do not react to a magnetic field. That is because there are only a hand full of elements that do (nickel, iron, and cobalt). If none of these elements are used it is perfectly safe to get an MRI",
"Had a tiny fragment of metal in my eye just before an MRI. Thankfully, they gave my eyes a thorough going over before the scan. If they don’t know beforehand, they’ll ask what you do for a living. They knew I was a welder, hence the check. As an aside, just outside the room, they had an extensive playlist and you got to choose which music you wanted to listen to whilst being scanned."
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jyuv5z | Why can't photos that are smaller than 1 KB be uploaded to FB? | Technology | explainlikeimfive | {
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"From a CS point of view, could be for a number of reasons. 1: Waste of bandwidth ( Like opening up a connection socket for something so small could be seen as wasteful, regardless of size, basic networking requires connection sockets to be initialized before uploading / downloading ) 2: Pointless. Smaller than 1KB, the image either has a really small resolution or so little pixel detail that it's as good as a blank image."
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jz3q42 | Who creates or improves technologies like Bluetooth, Wi-Fi, Ethernet, USB, HDMI, 4G, 5G, etc. that are used in many electronic devices? | Is there an organization responsible for creating these new technologies? | Technology | explainlikeimfive | {
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"In order for communication technologies such as Bluetooth, Wi-Fi, and USB to work correctly between devices, the manufacturers must make sure that their products behave in a consistent way. Otherwise, anything else that tries to connect to that product won't be able to communicate correctly. The most common way of ensuring this is to adhere to a technical standard. A standard is a technical document that contains the entire description of the way that a certain technology should work. If the technology has a connector, like USB or HDMI, then the standard specifies what shape and size it needs to be. If the technology is wireless, like Wi-Fi and Bluetooth, then the standard must specify the radio frequency and power of the transmissions. How the data is encoded (converted from meaningful information like letters and numbers into electrical signals) is also specified, along with control signals and commands that are used so that devices can set up the link to work for whatever they need it for. A technical standard can theoretically be written by anybody, but the most common ones are generally created by dedicated standards organizations or groups of companies that collaborate to create one standard for them to share. It should be noted that not all of these technologies are specified entirely \"in one place;\" it is common for standards documents to refer to others that came before it, leading to improved or modified versions that fit a certain need or meet different requirements. So not all of these answers will be entirely complete, but they'll give you an idea of where to start looking if you want to learn more. * The Ethernet and Wi-Fi standards are both maintained by the Institute of Electrical and Electronics Engineers, or IEEE. This is one of the largest standards organizations in the realm of electronics. * USB was originally specified by a group of seven companies, including Microsoft, IBM, and Intel. * HDMI had similar origins to USB, in that it was initially created by a group of companies, including Sony, RCA, and Toshiba. Now it is maintained by the HDMI Forum, a group of more than 80 companies. * Bluetooth was once specified as IEEE 802.15.1, but is now maintained by the Bluetooth Special Interest Group. * 4G and 5G are maintained by the International Telecommunication Union Radiocommunication Sector, with some support from the IEEE in specifying wired communication standards between wireless transmitters and receivers. Technical standards, especially widely-used ones like these, are very comprehensive documents that cannot be updated lightly. A great deal of thought must be put into any change to ensure that it will work correctly and reliably, and if a standard changes too frequently, then it becomes useless because it is a moving target. Standards are updated from time to time, however, as technical capabilities expand and users' needs change. This is usually done by the organization that created the standard in the first place, unless the responsibility is transferred to another group or if somebody creates a new standard based on a prior one. Take USB, for example, where the USB 3.0 version replaced the 2.0 version with much higher speeds.",
"There are organizations. The IEEE is one that standartizes electronics for example. They don't create everything though, they mostly coordinate and write specifications But these standards can also be started by a single company and then just be used by everyone.",
"Scientists and engineers create new technologies or improve them. These groups can be funded by governments, private or public corporations, or any combination thereof. Legally it mostly comes down to who owns the patent, but it's rarely as simple as any one entity 'creating' a new technology, because it's almost always the culmination of many different inventions and discoveries along the way. For example the CSIRO (Australian government research agency) is widely credited as \"inventing\" Wireless LAN aka WiFi. What they really did was essentially figure out a lot of the maths and engineering involved in encoding data in radio transmissions fast enough for a local computer network. Radio itself already existed, as did binary encoding, and GPRS (the first widespread mobile data network) was developed around the same time. Once the technology is developed, the standards and protocols around the use of that technology for a specific application is developed. This can be created and maintained by a dedicated standards group like the IEEE or ANSI, a single company, or more often a conglomeration of multiple companies (including partners and competitors) working together for their mutual benefit."
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jz52v7 | if every bit of steel produced since 1945 contains radioactive isotopes, is that eventually going to bite us in the ass? Are there long term consequences of not being able to use modern steel for certain products? | Technology | explainlikeimfive | {
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"1) Steel is 100% recyclable. We can reuse old steel from before 1945 again and again forever. 2) The producers of products that require low background steel are not massive consumers of steel, so our current supplies of low background steel are more than enough for the foreseeable future 3) We can make low background steel. It's just cheaper to use option 1 4) Background radiation levels are dropping. In the very long term, it stops mattering.",
"URL_0 It's going to matter a bit more when we run out of steel from old sunken ships from before the Trinity test (July 16, 1945). The radiation is coming from two possible sources; the atmosphere (since they're using oxygen pulled from the air in steel production), and in recycling metal (where there's a chance they'll end up with trace amounts of cobalt-60 and other impure metals). That page points out some examples of machinery we use low background steel in, which really aren't that many. Still like you say, we're running out of it (slowly). The shining ray of hope is that the amount of background radiation has gone down (a lot) since the ban on nuclear weapon testing went into effect. That doesn't mean it won't have some radiation to it - that wiki page points out that 0.11 mSv/yr *was the record high* for background radiation; and that now-a-days, it's 0.005 mSv/yr above natural levels. That is for the *world* background radiation, not necessarily the *steel* radiation. Regardless, we won't have truly 100% radiation free anything for a very, very long time. And when it comes down to it, and we've used all the steel from those sunken ships, we'll just have to retrain people on how to properly use those instruments, tools, and machines, to tell false positives apart from actual readings - or similarly adjust how we analyze readings from those instruments to account for radiation coming from the steel.",
"It's possible to make low-background steel for things where the light irradiation matters, but right now what we do is salvage steel from shipwrecks from before the first nukes."
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jzfb38 | Difference Machine Learning/ Deep Learning | I'm a teacher and I'm trying to explain the difference between Machine Learning and Deep Learning. Can someone help me? | Technology | explainlikeimfive | {
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"Deep learning is a specific part of machine learning which uses multiple layers as part of a neural network. Machine learning in general doesn't need to use many layers or follow a neural network architecture at all.",
"Machine learning is the part of AI that uses statistics and optimization techniques to learn from data. Other parts of AI are expert systems (Excel, Photoshop) and symbolic AI (video games), but most of the time the term AI designates machine learning. ML uses a variety of models that have different abilities to capture structure in the data. A simple one is linear regression. Deep learning is the part of machine learning that uses a particular family of models: deep neural networks. Deep because they use a succession of layers of artificial neurons, the output of a layer being the input to the next one. In practice, neural nets are just a sequence of matrix multiplications and non-linear functions, plus optional fancier stuffs. Neural nets are particularly powerful for sensorimotor tasks: vision, hearing, language, playing games (and somewhat moving robots but we're not quite there yet). For tabular data (of the type you find in an Excel spreadsheet), classical machine learning models (non deep) like random forests and gradient boosting, are often a better fit."
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jzg39c | Why do video games today have very realistic looking cities and objects but relatively unrealistic looking characters? | Technology | explainlikeimfive | {
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"Mostly because humans are really good at detecting imperfections in humans. Likely the humans in video games have much more detail and work put to them, but the bar for a \"realistic looking human\" is much higher. This is something you can also test yourself! You can likely draw a mostly realistic-looking house with perspective and a ruler, but drawing a realistic human is really damn hard. Even drawing realistic hands is a challenge most never conquer.",
"Short answer: Because creating a non-stylized human likeness is *really really hard*. [Long answer]( URL_0 )",
"* People are naturally very good at recognizing human faces, so we notice more imperfections. * It's easier for computers to draw simple flat surfaces (like walls and roads) than complex curved ones (like human bodies). * Color of the skin is actually very complex. Your body is slightly transparent! If you shine a light through your skin (e.g. try through your hand), you'll see the light becomes red. People notice this effect in real life, and can tell between the real skin and skin-colored plastic. In games it's very difficult to reproduce this effect (called sub-surface scattering), so games often draw people as if they had skin-colored plastic. * Things that don't move in games (like buildings) can have details like lights and shadows adjusted manually by graphic artists. If buildings don't move, their shadows won't move either. This allows calculating their look ahead of time (when the game is made), and it can be done very precisely. Things that move have to adapt to changes in their environment, and cast new shadows wherever they move. That requires the look to be automatically recalculated by the game engine, and it has to use less precise methods to calculate everything instantly.",
"Because of the Uncanny Valley. It's \"the appeal of a character rises the more human it looks, but there is a point shortly before complete realism, where the design becomes extremely repelling\" URL_0",
"As you can see there are many answers, so here's one more: Humans have an easier time forming psychological connections with people in games when they are less detailed graphically. Undertale is a great example. People would've had a much tougher time caring about characters if they were laid out in full detail with no room for interpretation. A really interesting example is Niko, the main character from OneShot. We all had to just agree to not correct each other when using various gender nouns to refer to Niko, because he's a child with a gender left intentionally ambiguous. So everyone just decides whether Niko is a boy (as in my case) or a girl (as with many others) and it lets you create a stronger emotional bond to what amounts to a few pixels and some dialgoue. so if you want people to form a stronger connection to your game, you leave the characters as undetailed as possible"
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jzh3a3 | If nuclear power plants put out so much energy compared to the traditional power plants why arent they used everywhere? | Technology | explainlikeimfive | {
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"Aggressive campaigning and “donations” made by oil and gas industry to make people think that nuclear power plants are unsafe. Chernobyl didn’t help the public perception of this.",
"1) Like other said there is a lot of fearmongering here. People are affraid of what they don't know, radiation sound scary and the few accident have such an impact on people. 2) Economics. Nuclear power plant are usually cheaper to operate because of the lower cost of fuel, but the cost of building the power plant is usually significantly higher. This mean that to build a nuclear power plant you need larger debt to build it, and it will take more time before you pay off that debt and start to get profit. At that point the profit will be higher, but it will take several years to get there, which make building a power plant a more risky move. Here a very good video on the subject. [ URL_0 ]( URL_0 ) 3) At the end of the day, nuclear power plant are not that efficient price wise. The expansive construction, decomission, treating the nuclear wastes, etc kind of balance the lower cost of fuel. In specific location, several other source of power can cost less than nuclear power. That said, nuclear power work everywhere. So if have geothermal, an easy access to natural gas or a flow of water for hydroelectric, nuclear power is probably not a good option. Everywhere else, the price of nuclear would be advantageous.",
"Fearmongering, lobbying and the word Chernobyl making everyone hesitant. People have been made afraid of what is basically fancy steam power plants because of the chernobyl and Fukushima incidents where reactors had major issues. The oil and gas companies pay a lot of lobbyists to act in their interests and keep lawmakers and the general public afraid of and against nuclear power.",
"Nuclear power is cheap once the plant is built, but building nuclear power plants is expensive, time consuming and prone to cost overruns. There are many good reasons to be pro-nuclear, but the simple fact is almost no company or country has been able to build them in a cost-effective manner.",
"1) Power plants can be used to make dangerous nuclear materials for weapons, so some countries don't want other countries to get them (or put restrictions on it). 2) The public in general is afraid of nuclear power because of incidents like Chernobyl in Ukraine, Three Mile Island in the US, and most recently Fukushima in Japan. Even though they are by and large far, far cleaner for the environment and able to produce a ton more power than regular fossil fuel plants, people are afraid of what can happen on the off chance something goes wrong. 3) Globaly we ARE building and increasing our nuclear power plant capacity. It's just slow going.",
"I don't think it's been emphasised enough just how much nuclear power plants cost, at least when you factor in things like construction cost overruns and decommissioning. The UK has been trying to build a new generation of reactors for a decade now and it's been going extremely slowly in large part because the companies building them require massive subsidies and guaranteed prices well above market rates. For example, the construction cost of Hinkley Point C, a 3,260MW reactor, is currently estimated at £21.5-22.5 billion (an increase of around 10% on the initial estimate). It will cost consumers an estimate £50 billion over its lifespan(?) in higher electricity prices."
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jzjs8l | How in the world does zipping a file work? How can a much smaller file still contain all the same information as multiple, larger files? | Technology | explainlikeimfive | {
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"Large file: AAAAAAAAAAAAAAAAAAAABBBBBCCCCCCCCCC AAAAAAAAAAAAAAABBBBBBBBBBCCCCCCCCCC Small file: 20A5B10C 15A10B10C If the program (Winzip or 7zip) can interpret the small file’s “code”, it can reproduce the large file at any time just from the small file’s instructions.",
"\"Lossless\" compression like ZIP: identify patterns and repeated sequences in the data, replace them with a smaller sequence so there is less redundancy or unneeded data in the resulting file. Replace all my \"the\" in the previous sentence with \"3\", \"re\" with \"R\" and double letters with the upper case version and you get > LoSleS comPRSion: Rplace 3m with a smaLer sequence so 3re is leS Rdundancy or uNEded data in 3 Rsult \"Lossy\" compression, like MP3 and JPG: having studied how humans perceive images or sounds, throw out the least important data which doesn't affect how a person will interpret the result very much. JPEG splits an image into 8x8 pixel blocks and records how the colour changes across that block, not the exact colour at every one of the 64 pixels. MP3 loses some very high frequency information which mostly doesn't change the sound because humans can only barely hear it.",
"Let's zip your question: How\\_ in the\\* world does zipping a file% work? \\_ can a much smaller % still contain all \\* same information as multiple, larger %s? We zipped your question from 136 down to 130 characters by encoding repeated words with single characters (\"How\" with \"\\_\", \"the\" with \"\\*\" and \"file\" with \"%\"). There are many smarter ways to compress files. Also, large files have a lot more repeated patterns.",
"The most commonly used algorithm for zipping files uses two things: First, it looks for duplicates: The program reads through the text, and if it finds a word or sequence of words that were used before, it replaces the entire thing with a number pointing to the location where it was first used. So for example \"this is a duplicate duplicate\" would become \"this is a duplicate 10 9\". Now to restore the text, you have to go back 10 characters in the text and take 9 characters from there. In the second step, it tries to reduce the amount of space that is used for each letter. To do that, it uses a so called *binary tree*, which is going a bit beyond eli5. The simple version is: Normally, text is represented as single string of 1s and 0s, without spaces or anything else inbetween. In order to make sense of this, every character needs to be the exact same size - typically 8 bit. This way, the computer knows that every 8 bit there is a new letter. The binary tree is another way to solve that problem. It allows frequent characters such as the space ' ' or the 'e' to be shortened to just 3 bits - but to make that possible, some characters like the 'Y' might become 10 bits instead. Now obviously, both of these only work for data that is highly repetitive like text and also program code. But for other media types, this is inefficient, which is why there are specific image, video and music compression formats (which are usually waaaay more complicated than this).",
"From a very far-away view, it works by the virtue of data you handle not being random. Every compression algorithm, when given random data, would result in larger filesize. But your pictures, text documents and such are not random. They are in many ways predictable and with structure into them. For example, text documents use 7 or 8 bits per character, and with those bits you can display 128 or 256 different characters. But just the fact that it's a text document means it probably has majority of its characters are letters and whitespace, maybe punctuation. That's only about 60 characters, so if you are smart, you can probably use only 6 bits per character majority of the time. Further, words are not random either. There have been studies about this and in English language literature, each character only has about 2 bits of information to them. So 8 bits could be turned into two. Further, many programs use even more rigid preambles or structures as they save files to notate where their stuff is, yet again making the text more predictable. As a result, especially text compresses extremely well. You should note that I did not tell how to use this predictability, but it should be helpful in reading other explanations, to keep in mind that it's all about leveraging the fact that the data is not random. As an anti-example, mp3 or video files compress exceedingly poorly, almost none at all, as they are already compressed quite well, and as a result, the data in video and picture files tends to be very close to perfectly random. And if you want to see zipping produce larger file than original, URL_0 should work. Save random bytes to a file, and try to zip it.",
"When you zip a file you're \"compressing\" it. This process consists of eliminating useless/duplicate info for storage. For example, lets say that you're saving a 200 page word file, and that contains the word \"the\" 900 times. That's 2,700 letters taken up just to show the word \"the\". Instead we can replace the word \"the\" with a placeholder like the number 7. That's 2 characters less, or a savings of 1,800 characters. Then when we \"unzip\" the file the program will go back and fix this and replace all of the 7's with the correct \"the\". No consider the fact that languages tend to have only a handful of words that make up the majority of our communication, and suddenly you can replace 60% of your document by swapping out all of the \"the, a, or, you\" type words, and see some serious reduction in file size. This works great for text files, but images/music/movies don't have anywhere near the amount of savings potential, so they're not as easy to compress. To the point that compressing them actually winds up ditching \"useless\" info that impacts the quality of the file."
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jzn1pu | Why do megaphones have such poor audio quality when we have microphones and speakers of a much higher quality? | Technology | explainlikeimfive | {
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"The amps in a megaphone have a much better frequency response to higher frequencies. In fact, typically anything below 90Hz gets cut off completely. Why? Most of the \"information\" in human speech (100-120 hz) is in higher frequencies. i.e. if you cut out anything over 105 it will be impossible to make out anything but a muffled wah wah wah sound (Charlie Brown adult voice). But cutting out 90Hz or below and you still hear distinct words. So the amplifier is designed just to boost 90Hz+ very loudly and clearly. Since megaphones are designed to amplify human speech, not \"all sounds\", you lose the low frequency stuff. If you want to amplify a complete frequency spectrum, use proper performance amps and speakers."
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jzqsrm | Why do computer screens use RGB instead of RYB (primary colours)? | Technology | explainlikeimfive | {
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"Additive light (emitted light) works differently to subtractive light. Subtractive light absorbs light in all the colours but the one you see. A tomato absorbs all but the red wavelengths, which it reflects. The more colours you mix with subtractive light, the more are absorbed. With [additive light]( URL_0 ), you get yellow when you mix red and green.",
"RYB are the primary \"subtractive\" colors, while RGB are the primary \"additive\" colors. Basically, a yellow dye/paint looks yellow because it absorbs every other color; your brain only sees yellow, so it interprets it as yellow. Additive colors in screens don't work like this, since they generate their own light. When they show blue, the only color hitting your eyes is blue, so your brain interprets it as blue. Both models can mix colors to generate secondary colors. Red and yellow paints can mix to show orange. Red and green lights, when mixed, show as yellow. But the truth is shown when you mix all primary colors together. If you mix red, yellow, and blue paint, you'll get a dark grey, brown, or black, because all of the pigments are absorbing almost all of the light and letting very little reflect. In contrast, when you shine red, green, and blue lights at a surface, you'll get a white light, because light of all colors is being projected onto the surface."
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jzrqhb | Why do electronics have first party and third party accessories but not second party accessories? | Technology | explainlikeimfive | {
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"Second party would mean the customer’s own accessories. In a transaction there’s the first party (seller/producer of the item), second party (purchaser/receiver of the item) and a third party is the different company that makes accessories. So this would mean you’re making your own USB-C cables for example",
"I suppose you are the second party. If you created an accessory, it would be a second party accessory. Solo cup speakers FTW!",
"It’s the same thing as points of view. First person would be me talking about myself (I am, we are). Likewise first party accessories are those made be the company for themselves. Second party is me addressing you, you are the second party, therefore from the point of view of the company making the initial product, you are the second party. Third party (he is, they are) is any other group of people. In this case it’s somebody other than the original company making a product for their device. Example: First party: Apple Second party: you, the consumer Third party: skull candy making headphones that you use with your iPhone."
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jzs6x4 | Why do we use radiation to sterilize our medical equipment? | Technology | explainlikeimfive | {
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"text": [
"High energy light is relatively easy to produce and very effectively kills living things. It carries no risk of secondary exposure because it leaves no byproducts behind. Really the only disadvantage of it as a sterilization method is that some products are, themselves, damaged by high energy light."
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jzup67 | How does a 1920x1080 resolution screen display media in lower resolutions, such as 1600x900, when the ratio between resolutions isn't a whole number? | For example if a 1920x1080 screen is displaying a 1600x900 image, the ratio between resolutions is 6/5, meaning that every 6 pixels which physically exist in the screen are supposed to display 5 pixels which are in the image. How does the computer handle this? This is all in a fullscreen context of course. | Technology | explainlikeimfive | {
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"text": [
"It interpolates the difference. There are many, many techniques to do this - some are super dumb like just removing every X pixel. Others are very sophisticated and involve looking for patterns or maintaining certain colours where they produce a high level of contrast (on the assumption that this is likely to be visually important and thus useful to maintain). As a result, different types of scaling can produce really quite markedly different results, and it works in both directions - removing pixels which are there and adding new ones which weren't originally there.",
"Image scaling. There are many different algorithms to decide exactly what pixels to leave out or blur together in different situations so our eyes fill in the missing detail correctly."
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jzuxwl | Why do sports like boxing still rely on the referee for counting a knockdown/starting the count when there are much better and more accurate technologies that are available to us now? | Technology | explainlikeimfive | {
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"text": [
"Boxing has a designated timekeeper for keeping track of the seconds once the boxer hits the ground. The ref doesn't just eyeball it."
],
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jzuyyr | What's the logic in sending signals to outer space | If a society was so advanced as to be able to receive signals and had faster than light travel, what's the logic in contacting them? Was there ever a determination made that they're more likely to be peaceful than violent? | Technology | explainlikeimfive | {
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"text": [
"1. There's no guarantee, or even any indication that they would have FTL travel at all, indeed, all signs point to that being an immutable physical law, despite science fiction's claims to the contrary. 2. We are sending signals out anyway, even if we didn't want to, and have been since the early 20th Century. 3. Any response at all would be one of the turning points of the species, for better or for worse. Learning of other life that can communicate on the scale that we do would be the discovery of the millennium, which some think is enough to try.",
"Yeah, they've thought about it a little. :) Here's a NASA publication about it from 2014, and I'm sure there were others written before the Voyager launches. See especially Ch 9 p 142. URL_0 Very short version: because space is big, detecting a transmission is all that we can see happening in the near-to-mid future. A detection is orders of magnitude more probable than a conversation, and a conversation is many orders of magnitude more probable than an invasion fleet. Also, our radio broadcasts are out there already so we aren't making ourselves more detectable, really. We're just including some messages of greeting and goodwill along with our onslaught of dish soap commercials. :)"
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k02g3y | How does a GPU converts data to a picture/ graphic on the screen? | Technology | explainlikeimfive | {
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"text": [
"Picture on screen is also data, just several numbers for each pixel on the screen specifying which color it should be. GPU just builds that array by doing some math to determine which parts of 3D models you should see, and how their color is changed by light effects and so on.",
"Answering the question a bit differently, in case you meant something more like \"how does the gpu do 3D stuff\" Go look at a picture of a cube. We know all of the sides of a cube are square, and when we look at a rendered cube it looks like a cube. But just trace out the shape of one of those faces on your screen. The image represents a 3D cube, but this face on your screen is likely a squashed weird diamond shape. In context this looks to us like a square face that's facing slightly away from us, shrinking into the distance, but in the final image it's actually not a square anymore. It's a trick. So essentially that's the job the GPU does in 3D graphics. The GPU is sent a bunch of 3D coordinates for the corners of stuff, and then it does some math on those corners to figure out where each of those 3D points would be in this 2D image. Then, once it's found each of the corners of the 3D square, that'll give four corners of the 2D \"square\", and it can just colour in between these lines in 2D and it'll look 3D to the human. Now, any real scene will likely have millions of corners, but they're all mostly having the same math done to them. Also, computing where one corner is is entirely independent of computing another corner, so we can do them both together. So the GPU has a ton of simple calculators inside that are really good at doing exactly this one kind of thing, over and over, and with many going on at once. This is what allows them to get so much more on the screen compared to a CPU, and better GPUs have even more calculators and can do even more corners even faster."
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k06rgy | Explain bandwidth and data consumption to me please. Why do phone and internet companies charge so much extra when we’re not actually consuming anything? Is there a finite amount of data out there? Is it just a huge scam? | I’ve always wondered about this. It’s not as if there’s a silo out there somewhere that has all my potential data sitting in it. So why do they set limits on how much data we’re able to consume each month? As a dumb person, it seems like it’s simply an exchange of information. Nothing is being consumed. So why do they charge so much? | Technology | explainlikeimfive | {
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"There is a limited frequency range that cellphones can use. When you broadcast stuff it is a shared media so in a single area, a single cell tower can use a single freq range. A cell tower will have a limited amount of data is can transmit each second that is shared by all customer in range. The result is if more customers use more data each second you need to have more towers that each cover a smaller area. The tower cost money to build, operate, and maintain. So there is a max capacity for the current system a cellular provider has. If the customer use more than it can handle you need to add more stuff to it and that costs money. So the data limits are ways to keep the usage down so your current network can handle it. Low limits and your customers will likely move to a competitor with higher limits. To high limits and the usage can be so that you need to expand the network. So the existing cellular networks have a finite amount of data they can transmit each second. For the current standard, there is some max possible speed to as each cell has some minimum area and there is a limited frequency range you can use. In practice is more about cost limitations, but physical limits can be relevant. For stuff that uses wires, each wire is independent. So you can put as many fibers side by side as you like. So you can increase the capacity to any level you like. The problem is fiber or other cables cost money to purchase and dig down. The equipment on the end cost money too. So wired internet sometimes has max data limits even if it is uncommon. There is of course physical limit in how many fibers can exist on earth but the capacity for each is enormous. So in practice is it a cost limit. & #x200B; Of course, there is companies that use it as a way to charge more money for customers. But in general, it is a good idea to encourage people to not just use the cellular network but a wired connection at home too. Downloadable games can be many GB in size. 4K video streaming use a lot of capacity. With the 4G cellular standard, the consumer cost would be enormous if you tried to replace all wired networks. I suspect the standard can handle that. 5G will be better but still, a high-speed wired network to homes will likely reduce the cost for the consumers."
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k07vb2 | Why does warm air blow down on you when you exit some buildings through automatic doors in the winter? | Technology | explainlikeimfive | {
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"text": [
"They are air curtains. The concept is that they are using airflow to prevent the warm inside air from escaping out and the cold outside air from coming inn. And just in case some outside air does get inn they make sure the air that forms the inside part of the air curtain is kept at a higher temperature then the rest of the store so that it will heat up any of the cold outside air coming inn to room temperature.",
"It's an \"air curtain\". A powerful fan blows a wall of air across the opening to reduce energy loss. Especially useful for doors that are used constantly such as supermarket entrances or a walk in cooler."
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k0c6kw | How do research labs achieve temperatures near absolute zero? | Technology | explainlikeimfive | {
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"text": [
"To ELI5-ify u/Fenriradra s answer a bit: Ever pumped up a bicycle tire and emptied out a spray can? And feel them get hot / cold respectively? You basically do that. A lot. And then some more stuff that is essentially magic. So you take a gas, like nitrogen or helium, compress it (bike pump), wait for it to cool down again and then let it expand (spray can). Now you've got a colder gas that you can compress again. Repeat until your gas is liquid. With liquid nitrogen you can get worn to 77K (=Kelvin, in case you're unaware. It is basically degrees Celsius, but starting at absolute zero, so water freezes at 273,15K) or - 196°C. Liquid helium gets you to about 4K, reduce the pressure of it a bit with a vacuum pump, that gets you down to about 0.8K. If you've got loads of money you can buy some 3He (I wont ELI5 [isotopes]( URL_0 ) here, sorry) and get down to 0.3K Those temperatures are the boiling points of the gasses, just like water, when it boils is at 100°C (or 373K) under normal conditions untill all has boiled off, so are these liquified gasses, just colder. Reducing the pressure reduces the boiling point, too (boiling is, essentially atoms / molecules escaping from the liquid. If there's less pressure in the gas above the liquid, it's easier for them to \"get out\"). Now < 1K isn't all that bad, and for most things it is plenty cold, but if you want to go lower still, it's difficult, but possible. Up no now things are not to moderately difficult, assuming you can just buy your liquid gasses ;) and have a \"cryostat\", basically a huge, fancy thermos flask where you can put whatever you want to cool in. The main difficulty is that at low temperatures, you need a lot less energy to heat something up by a certain amount. If you're heating water from 1°C to 2°C you need the same energy as for going from 98°C to 99°C. It is ***a lot*** easier to go from 1K to 2K than 98K to 99K. If you put a temperature sensor in your freezer at home and have a cable go out through the seal the freezer can deal with the small amout of energy easily. If you put that in your nice helium cooled freezer the heat conductd by the copper wire from the outside might be enough to warm up the whole thing. So you need to be very clever building this. (As for [why this is]( URL_2 ), that again makes a great ELI 5 \\[or 15 or 25\\] for someone else). But, let's say 2K isn't enough, you want to go lower. Now the magic (or rather, advanced thermodynamics) happen (again, really, another new ELI 5 \\[or 15 or 25\\] for someone else). When a liquid evaporates, it takes energy from its surroundings, you can feel that when you have some liquid on your skin, for example. [You can to something like that with 3He and your regular old helium 4He, where concentrated 3He evaporates into a mixture of 3He and 4He.]( URL_3 ) This will get you to soemthing like 0.002K. There are [more ways]( URL_1 ) to get lower, still, but this is quite long already and stuff only gets more complicated frome here."
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"https://en.wikipedia.org/wiki/Timeline_of_low-temperature_technology#20th_century",
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"https://en.wikipedia.org/wiki/Dilution_refrigerator"
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k0czkg | Why can my iPhone recognize my face to unlock when I’m wearing big sunglasses, but not when I’m wearing a mask (like a cloth mask , not a Halloween one)? | Technology | explainlikeimfive | {
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"text": [
"Because it scans your facial *features* not your eyes. It mostly looks at the shape of your face. The mask obscures that, sunglasses obscure the top half, which it doesn't focus as much on.",
"Space and size/proportions of your face, dimensions in between. Mask hides it all while sunglasses just obscure a few points up top."
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k0e9ia | How do radio stations or local cable channels come up with names like WBZ, WGBH, or KTZ? | I never understood how they got their names | Technology | explainlikeimfive | {
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"The identifiers are assigned by the FCC when you are granted your license to broadcast. You can request any 3 letter call sign that is available, but if it is taken you get what you get. The K vs W distinction tells whether you are west (K) or east (W) of the Mississippi river (though their are a few exceptions. There is also N, but that is for military broadcasts.",
"W and K are the International designations for the US. Other countries start with different letters.",
"They didn't. These are the station ID letters assigned by the FCC to regulate their transmitters. They are legally required to say or display them pretty often, so the marketing guys see this as a branding opportunity. K means west of the Mississippi river and W means east of it, the two regions the FCC established when they started the station identification process. I think you can request letters that are not in use, but otherwise, you just get the next one off the list."
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k0eeev | How do custom email domains work? | So from what I understand (and my understanding might be mistaken), when I want to get a custom email domain, I can choose literally anything I like. This doesn't really make sense to me because when I want to use a normal web domain (for a website), it needs to be one I own. To give you an example of what I mean, Google owns the URL_1 web domain, and so when I send an email to an account that has @ URL_1 it goes to Google servers. That makes sense. I want to get a custom email domain for my imaginary business, and I want it to be @ URL_0 , but I don't own the _web_ domain URL_0 . If my understanding is right, even though I don't own the URL_0 website, I can still receive emails with an @ URL_0 domain through Google's custom email domain service. How is that possible? Why wouldn't emails sent to that account go to a server that isn't mine? If my understanding is mistaken, then I must own the web domain before I can setup an email domain as well, right? FWIW, I do have some understanding of DNS and how the web works in general | Technology | explainlikeimfive | {
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"You need to own the domain\\*. A domain is not protocol specific, it's what's used to route all TCP/IP requests to that domain. The DNS isn't just used for web. \\* - If you have an agreement with the actual domain owner to forward your email elsewhere then you don't need to own it, but you do need the domain owner to work with you. That's how you can have a @gmail address without owning @gmail.",
"Your understanding is wrong. You have to own the domain name, and then you own it for everything: website, email, etc. Once you own the domain, you can use whatever you want (within the limits of the email address standards) before the @, so you can be inbox at URL_0 if you want."
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k0ikqe | Why does your Wifi/Internet stop working if you change your date and time too far? | It took me two hours to realize why i couldnt watch Youtube. It was because i changed my clock on my phone at least 5 years ahead to cheat my way into a game I was playing. Why does it do that? | Technology | explainlikeimfive | {
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"Most of the traffic on the internet these days is encrypted and encrypted traffic has certificates that expire. Youtube's current certificate for example doesn't expire until 1/26/21 but if your phone's clock is set to way after that and Youtube hands that certificate to your phone, your phone is going to think the certificate is expired and refuse to connect to the website.",
"Your internet still works, but your browser refuses to connect to most websites. Websites that use encryption to secure the connection between the browser and the server have a digital certificate, and that certificate is only valid for a certain period of time. When your computer thinks it's 2025 and the website certificate is only valid until 2021, that certificate is already expired as far as your browser is concerned, and since a connection using an expired certificate is potentially unsafe, it refuses to connect."
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k0isjq | When old movies say "Filmed in Technicolor", what exactly does that mean? | Technology | explainlikeimfive | {
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"It was one camera that had several mirrors in it. Those mirrors reflected the image in front of the camera down 3 different channels. Each of those channels had a filter on it that only allowed one color of light through: red, green, and blue. After passing through the color filter the light would be captured by a piece of black and white film. So now you have three pieces of black and white film, but what each piece of film is *really* telling you is how much of the one color that it had been exposed to was present in the scene. Once you have those three strips of film you dye them to match whatever color they had been exposed to. You now have 3 sets of film which you can place on top of each other to get a complete color picture. But they would go a step further and press the three single color channel films onto a single piece of blank film to create a piece of film with all 3 color channels on it. The process had some shortcomings - notably that each piece of film was only exposed to 1/3 of the total light present. This required the use of blindingly bright lights on the set. Even then, it produced a somewhat darker, more saturated picture than what was being captured such that technicolor films have a very distinct and easily recognized color profile.",
"Technicolor is a patented process, actually several processes, to develop and print film. The company exists today as a commodity film processor and holder of an impressive intellectual property portfolio. The result of the process is distinctly rich color and strong shadow contrast. The distinctive look of Technicolor was a draw for movie audiences from the 30s forward. Shooting of film and Technicolor could cost as much as six times the cost of shooting conventional color by any other method. Therefore, it was used primarily for travelogues and otherwise very high-budget productions."
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k0lk5z | How did Turing break enigma? | Technology | explainlikeimfive | {
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"The structure and function of the Enigma cipher was mostly worked out by other intelligence operations exploiting operational errors and misuses by improperly trained German troops. When someone screwed up and transmitted the same thing twice but with different keys, or started transmitting the message in plaintext and then stopped, performed an encryption, and then transmitted again, this allowed Allied cryptanalysts to make deductions about how the Enigma worked structurally. Eventually, captured equipment helped them fill in all those gaps. The thing was, knowing how it works structurally doesn't necessarily mean you can decrypt the messages, you also need to know the key the messages were encrypted with, and that key was changed every day. Turing worked out how, given a sufficient number of messages encrypted with the same key, to make some deductions about what that key must be - and critically, he designed an electromechanical device which could *perform* this very complicated calculation, which he called a bombe. From then on, cracking the codes was just a matter of running the bombes every day on that day's intercepted messages, and letting them crank through the calculations until a key was found, and then everything could be read.",
"One of the giveaways is that many transmissions ended with \"Heil Hitler\", so that helped identify some sort of pattern. Another was that letters would never be encoded as themselves, which reduced the number of possible combinations. See URL_0 ."
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k0lrtp | Why do regular batteries last for so long whereas rechargeable ones have to be recharged so frequently? | Technology | explainlikeimfive | {
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"Some hold less energy but also the chemicals in rechargables produce a lower voltage (1.2v instead of 1.5v) lots of devices will detect rechargables as less than full battery even when fully charged since the voltage is lower. On top of that the voltage might drop below operational threshold sooner since they start lower. To add to that regargables degrade over time so eventually they hold less charge and wear out with greater frequency.",
"There isn't huge different between capacities, since they are somewhere around 2500mAh for modern batteries, it's just that some devices can't use all of that due to lower cell voltage. At around 1.2V standard alkalines are pretty much dead while NiMhs still have about 40% of capacity. So with around 2500mAh cells, you are only getting about 1500mAh. That means that if device was designed to shut off at around 1.2V, you might get 30 min of use for device that might last 1 hour with standard batteries. Rechargeables also have higher self discharge, which means they shouldn't be used in low power devices like clocks or TV remotes since they would drain itself in few months (there are low self discharge versions, but they still have higher self discharge than alkalines and they cost a bit more).We also tend to use alkalines in devices that aren't power hungry so they last long while most power hungry devices use rechargeables.",
"Imagine you've tied a heavy weight to a pulley up in the air. When you first did it, you had a tractor pull the weight to the top so you get the maximum thump when it hits the ground. After you've used it once, you aren't able to use the tractor again, so your buddies will help you pull it as high as possible. But, since you're all human, you can't quite reach the same height as the tractor did, so you all agree to give up somewhere near the top. When you let go, there's still a thump, but it's not as satisfying. The tractor pulled rock is a non-rechargable battery. The weight that you and your buddies pulled is the rechargeable one - not as efficient, but you don't need to borrow uncle Mickey's tractor to head down to the store and buy new batteries. The reason for rechargeable batteries not being as great is the concentration gradient - the electron slush inside the battery is designed that you can put all the electrons back into the right place, but as you get to higher charges, you end up working against the new gradient and it's just not worth it to get it to the 99-100% charge level, so your battery might top out anywhere between 60-80%. (Pure estimate, please don't quote me) I'm sure there's a university-level answer with a breakdown that mentions vanadium, but I tried for a ELI5 and then maybe a high school level in the third paragraph.",
"Besides technical reasons, rechargeable batteries are used where the energy demand is high, where you would have to buy single batteries often. Like laptops and phones. Recharging them often justifies the higher price. Single use batteries often go in low energy appliances like clocks and remotes, so appear to last much longer.",
"In addition to the other answers, it depends which ones you buy. Rechargeable batteries lose energy over time even if they're doing nothing but some lose it faster than others. \"Low self-discharge\" batteries like Eneloop will need recharging less frequently because they manage to hold onto more of their energy.",
"Rechargable batteries are more \"leaky\", they leak more energy by simply existing. An generic rechargeable battery can lose around 50% charge within a week, while a non-rechargeable can loose 50% in a years time. This leakiness is a property of the battery technology itself"
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k0n492 | why should internet's upload and download speed be different? Isn't it the same connection? | Technology | explainlikeimfive | {
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"You got a road. There is enough room for a total of 4 lanes. You know that there is WAY more traffic going north than going south. So as a smart road designer, you decide to put 3 lanes going north and 1 lane going south. That way you keep traffic fluid most of the time. The road is the cable, the lanes is the bandwith, north is download and south is upload. The total bandwith on a certain cable is limited, so the smart move is to put more of it on what is more often used: Download.",
"Some isp do offer the same speeds for both. Some however, provide way lower upload speeds to limit the bandwidth of the user.",
"It’s simply far more useful to dedicate more bandwidth for download than upload. It’s the vast majority of traffic, so dedicating anything but a small portion to upload doesn’t make sense. Some isp’s with excess bandwidth can afford to have more generous upload allocations, but it’s not the most cost efficient use of their pipelines."
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k0nppq | How do some stereo sounds sound like they are coming from both sides rather than the middle? | Example: when listening to music on headphones, the vocal is usually in the center, inside your head, whereas instruments sound like they're outside your head on both sides, even though the volume is the same in both channels. | Technology | explainlikeimfive | {
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"So the way our brains interpret the direction a sound is coming from is to listen for differences in the sounds reaching each ear. So when stereo speakers (placed at an equal distance) are playing the EXACT same sound, our brain interprets that as coming from directly in front of us. When an audio engineer is mixing music, it is sometime desirable to have some instruments sound like they are coming from the sides, but not necessarily one side or the other. To accomplish this, they have to make one side (either the left or the right channel) SLIGHTLY different from the other. One way this is accomplished is by a “Stereo Spread” which will take a stereo audio file and spread certain sections of the frequency band to either the left or right. That way the left speaker will be playing some of the frequency bands, and the right speaker will be playing the other frequency bands of the same sound. The other way this can be accomplished is by using the Haas effect. This is done by simply “delaying” one of the sides (either the left or right channel) by up to about 30 milliseconds; so one side is playing the exact same sound as the other side, but just slightly later than the other. By only delaying it as much as 30ms, our brain doesn’t detect it as being “out of time” and can barely tell the difference. However our brain DOES definitely hear two separate and distinct sounds in each ear making it interpret the sounds as coming from each side instead of directly in front of us."
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k0oca5 | why does resetting a computer fix most problems | Technology | explainlikeimfive | {
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"You've probably heard that computer programs are just sequences of instructions that you can string together to accomplish some higher-level task. That's technically true, but it might give the impression that what software engineers do is try to just think about a single giant sequence of instructions all at once. Since we use computer programs to do *really* complex things, that approach would break down pretty quickly for most real-world use cases. Instead, most programs are designed around \"invariants\". What this means is that, instead of trying to come up with a single giant sequence of instructions to accomplish some task, the programmer: * breaks the problem down into smaller tasks * makes sure that each task makes sure that certain properties are always true That second bullet probably seems really abstract and confusing, so here's an analogy. You probably try to make sure that, when nobody is in your house, the doors are locked. You probably accomplish this using the following two rules: * When you leave the house, lock the door. * When you leave the house, take the key with you. This ensures that whenever you're not in your house, the door is locked. It also ensures that, when you come home, you have the key to get back in. Now, this may seem so obvious as to be uninteresting, but that's kind of the point! No matter how many times you enter and leave your house, as long as you always obey these two rules, your house should never be unlocked when nobody is home, and you should never be locked out of your house. You can think of similar rules for things like \"make sure the fridge door is always shut when it's not in use\" or \"make sure the lights are off when I'm not home\". All of these are *properties* that you want to be true, and you make sure they're true by following very simple rules. In theory, there would be nothing stopping you from, for example, checking every 5 minutes to see if the fridge door is open. That way you wouldn't have to worry about shutting it every time you go to get food! But of course, this would be way more complicated. Much easier to just make sure that the fridge door is always closed when you're not using it, and then you just don't have to think about it the rest of the time. Computer programs are much the same way, but the properties that they're trying to uphold are *much* more complicated. And often, programs don't get it 100% right. When a program makes a mistake like this, it might never get corrected. It would be like forgetting to close the fridge door and then leaving for work - now your fridge is going to be open all day! With programs, the various properties you want to uphold often affect one another, so these sorts of errors can build up on top of each other. However, here's the kicker: The vast majority of the properties that programs on your computer try to uphold only exist when your computer is on. When your computer turns off, everything is forgotten. When you turn your computer on again, all of the programs start again from scratch. Did one of the programs leave the fridge door open? No problem, because by restarting the computer, you literally deleted the entire house and then made a new one when the computer booted back up. And that new house starts off fresh with its fridge door shut.",
"Because the problem is usually some fault with the data that is stored in RAM. When you use a program, it has to load everything into the RAM so that the CPU can perform calculations with the data. RAM just so happens to be what is known as \"volatile memory\" which means that it cannot sustain data in memory when there's no power running to the module (i.e. when the computer is turned off). So, turning your computer off and on again effectively resets the RAM. This is also why hibernation *doesn't* fix your problems. Hibernation is when the computer takes a snapshot of your RAM, stores it to the disk (non-volatile memory), shuts off power and reloads that data back into RAM when power is restored."
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k0opk3 | I saw a demonstration of an RF detector being brought close to a mobile phone. As the detector was moved away, the number on it dropped to zero. How can that be? Shouldn't there be some RF signal from the phone all the way to the cell tower, so that the phone can communicate with the tower? | Technology | explainlikeimfive | {
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"A mobile phone doesn't constantly transmit at the highest power available. It is mostly inert to save battery life and is only listening to transmission from the tower (which the detector would count as part of the \"ambient\" RF field and not show, like the tare function on a scale). It gets a lot livelier when it is trying to use its radio to transmit. In the receive-only state the RF detector probably only detects the small interference caused by the phone's internal power system and the processor/other digital stuff.",
"Electromagnetic radiation decreases at r² rate. So at 3 x distance from the antenna, it is 1/9th of the power, at 10 x the distance from the antenna is is 1/100th of the power. If the RF detector was set to a range then it would fall out of that range very quickly.",
"You may have heard of the inverse square law. Each time you double the distance, the power drops by four times. The power isn't actually zero. It's just low enough that it's below what the detector will indicate. (Cell phones work at incredibly low received power levels, both at the phone and from phone to tower)"
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k0u31n | Why does Wifi go down at midnight every day? | Technology | explainlikeimfive | {
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"Depending on your internet service providers infrastructure their systems might require a restart every day so they have it scheduled. You should reach out to them about it to figure out if that is the reason for it or if their is something else going on. I will say if the infrastructure is that bad that it requires daily restarts then if the option is available and financially feasible for you to switch I would switch. Edit for typos on phone."
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k10el4 | Why do rechargeable batteries only have 1.2 volts vs disposable batteries have 1.5 volts | Technology | explainlikeimfive | {
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"The electric potential depends on the specific chemical reactions in the battery cell, which are different for the different materials in different types of batteries. For example, due to the chemistry of a lead-acid car battery, each internal cell has a nominal voltage of 2.1 volts. Standard electrode potentials for different materials are listed in tables like this: URL_0 Some chemical reactions can be reversed easily by applying a reverse (charging) voltage to the cell, without destroying the battery cell's structure. Other kinds of battery cells would get damaged internally if you tried that, so those cells are sold as \"one-time use\" batteries."
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k1113h | Why are there suddenly so many arm processors coming out? | What has changed so that chip makers have moved from x86 to arm? | Technology | explainlikeimfive | {
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"There have been a steady increase in ARM chips around since about 2013. ARM chips are better then x86 chips in power consumption and production price but they have also been improving a lot in performance. The high end ARM designs are now much faster and more capable then the low end x86 designs. So all the devices that used processors like Atom and Celeron have almost all switched to ARM nowadays. And ARM based laptops and servers which first were introduced around 2013 are now competing with the likes of i5 based products. So we are seeing more and more of these as they have become more capable. But there is no big difference from year to year."
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k17kyh | Loading Screens in video games | Ok, so I get the game has to load and render right. But like once it’s done it’s done right? Why is there loading screens after every death just to put me back in a spot I was JUST at? | Technology | explainlikeimfive | {
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"The game needs to reset all the assets (i.e. the enemies, the environment etc.) to the state they were at the last checkpoint.",
"It also depends on how the game is coded. A particularly clever dev can keep the relevant information in memory and quickly load up the few things that are needed. The opposite dev may have the game dump the entire memory and load up everything again."
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k1a0je | how do astronauts in ISS post on social media? | I just saw an [article]( URL_0 ) about Victor Glover's first video from space. But some Facebook troll want to ruin the experience by saying "Geez he must have a good telecommunication deal to get service up there! I can't get it in my bathroom!" I know that somehow they "beam" signals to NASA receivers, and those are different from what the local telco providers have, but how are they able to do this? Can the astronauts really post real-time videos on social media from a mobile device? | Technology | explainlikeimfive | {
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"They are connected to the internet through a network of satellites. The satellites connect the ISS to a computer in Houston, from which they can connect to the internet.",
"There's a network of satellites in geosynchronous orbit as well as ground based stations that form a network specifically for supporting space missions that's run by NASA. It is actually just called the \"Space Network.\" The main difference between this network and a normal communications satellite setup, besides just not being pointed at the ground is that the satellites are able to track fast moving objects in space. As for the actual data that goes over this it's basically just a big LAN with a connection to the public internet the somewhere in a NASA control center. The ISS itself has WiFi for cell phones and tablets and such. As well as wired ethernet for experiments and stationary equipment. Also the same network is used for controlling and monitoring experiments on the ISS remotely from ground stations. Like the last spacewalk I was watching was literally just running ethernet cable to a webcam :D. Just, in space."
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k1e25z | If programs/app are made from codes, then if the codes are still there or still the same; why would programs/app get lagging and crashed sometimes? | Technology | explainlikeimfive | {
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"Writing code is like building a maze for water to flow through. The maze will have little gates that will redirect the flow of water depending on the circumstance. When the maze is operating under normal circumstances, the water will go where it is supposed to and the app will perform fine. However testing every combination of gate opening can be very difficult, and over time some obscure combinations of gates opened and closed is bound to occur. In those cases the water may get blocked and overflow, or form unwanted reservoirs that impede the performance of the app. Usually it can be fixed by resetting all the gates to a known good position and flushing out the water (restarting the app). The more complex the maze the harder it is to make it error-free.",
"Something has to run the code. The CPU needs to access data that is in memory to actually do anything with it. And sometimes the memory (or the CPU) is under more strain than it usually is, causing a slowdown of performance for some programs.",
"Because there are other external factors. Maybe the user uses the program differently. Maybe the computer is also busy running some other programs at the moment, which takes up precious CPU and RAM resources. Maybe the internet connection is misbehaving. Each of these can make some difference."
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k1hnf2 | Why are fight scenes and music so loud compared to dialogue? | Technology | explainlikeimfive | {
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"They are mixed for movie theaters and then not modified for the sound setups most people have at home. I don't get it either but it IS incredibly frustrating",
"It's because they are mixed for a full 5.1 sound system and for some stupid reason when playing in Stereo the center channel (the one with all the taking on) is never mixed in properly and thus sounds really quiet. If you play the very same movie with a 5.1 (or above) audio setup you'll find there's no problem hearing the dialogue as it's clearly coming out of the center speaker.",
"It's not only the difference between viewing in a theater and at home. See for example [Christopher Nolan Says Fellow Directors Have Called to Complain About His ‘Inaudible’ Sound]( URL_0 ). Some of them, like Nolan, intentionally mix the sound this way so that it's even a problem in theaters. He has all kinds of people, directors and audience members alike, complaining about it, but he still can't accept that he's wrong.",
"Because you are using TV speakers to play sound that was designed for a surround sound setup. if you had a center channel that you had tuned correctly, you would have dialogue coming from it that was well balanced with the rest of the audio in most cases. As it stands, your television is trying to squeeze sound from eight different speakers down into two, and it does a very bad job balancing volume levels. Some TVs have volume normalization settings in them that work okay. But the real solution is to get even a low end surround sound system and turn your center channel up until you are happy with the results.",
"Because Hollywood wants everyone to have the \"authentic theater experience\" which is pretty impossible at home. Its annoying as hell. I just set receiver to \"dynamic\" setting and bump up the output on the center channel higher than the L & R channels",
"I work in TV in the UK and we have Loudness regulations across the country and other European countries following the guidelines. The content needs to be averaging -23 LUFs give or take to be able to air. I think the recommended for the US is -24 give or take. Unless you’re watching a DVD or Netflix, it should adhere to this standard and the action would be similar volume to the dialogue.",
"While I'm not disputing the audio mixing that others have mentioned, I have read before that it is sometimes a sort of intentional sensory overload for the viewer. Most fight scenes are pretty terrible without the sound and it's extremely difficult to make one without the dozens of cuts that most scenes have. With all the flashes, bangs, explosions, and fighting being so loud your brain doesn't have the time to realize that most of those action scenes would be pretty shitty if you paid close attention to the actual action. Like I said, it's just something I read somewhere, but it makes sense. If you watch your favorite fight scenes on mute and pay attention to the fight a lot of them are pretty bad.",
"It's so annoying - when watching films at home I'm constantly adjusting the volume to hear dialogue / not be deafened",
"This is a problem with a lot of action movies, IMO. Also commercials are double the sound level than the actual film or series."
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k1i7vq | Why can't the telescope act as a microscope and vise versa? | Technology | explainlikeimfive | {
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"The lenses are not set up right. One has lenses to focus on something really close one very far away. The lens arrangement, size shape and position inside of an optic decides how it works."
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k1kxrx | How does the Apple Watch Series 6 measure blood oxygen levels? | Technology | explainlikeimfive | {
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"Dumbed down? It use special light... cover a bright torch with your fingers at night and you can see red light shining through... as your blood pulses it changes how much light gets through... the amount of light is also changed by blood oxygen levels. At least that's how it was explained to me."
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k1m00r | Why were there different melee weapons? | Like, the whole motivation must always have been; "kill the other guy", and there must always have been a best tool for the job right? So why am I aware of longswords, broadswords, bastard swords, katanas, spears, tridents, halberds, pikes, war axes, long axes, glaives, warhammers, maces, morning stars, orochis, kusarigamas, daggers, sais, bo staves, I mean, I could still go on for ages. I get bows vs swords and them serving different jobs, but for the rest, the instructions are; "Be near the guy" and "Kill him". | Technology | explainlikeimfive | {
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"Different weapons have different strengths and weaknesses, costs, cultural significance, and so-on. In fact, you say \"be near the guy\" but one of the key advantages if some weapons is that you can keep the other guy as far away as possible! To pick some examples quickly: Spears are perhaps the most common weapon up to the age of firearms. They're cheap to make, you can keep your enemy away from you, they're great in a formation. A downside is that they're not very good if an opponent does get close. So you want a backup weapon, like a sword. What kind of sword? Well not one that's too big, because you have to carry it around alongside your spear, and you're mostly going to be using it against people who are close anyway. But what about people in armour that makes them hard to hurt with a spear? Well maybe you want a halberd. This has reach and a spikey bit like a spear, but it also has an axe bit and a spikey bit you can hit people with. Plus you can use it to hook people and pull them over or off a horse. However it's also more expensive to make, and harder to use. Give a halberd to a peasant and they won't make the best use of it. Give it to a pikeman and he'll go \"can I have something longer?\" I could go on, and there are some really fascinating bits of history here - like how swords in Europe were more common than their pure military value because of their symbolism - but hopefully you get the basic idea.",
"Different cultures invented different weapons for various different purposes. Broadswords, bastard swords, katanas, spears, pikes and halberds maybe all different versions of \"stick 'em with the pointy end\" type weapons, but the different shapes have different advantages. Different cultures went through different evolutions of military tactics, and weapons were designed in order to respond to these military tactics. For example, the broadsword is common in Medieval Europe due it's effectiveness in fighting against people wearing plate armour. Where the curved blades like scimitars are more common to the Middle-East since combat more frequently involved riders on horseback (where curved blades have an advantage). Also technological advancements and materials available strongly influenced design. For example, the katana folded steel design was a work-around to make a good sword with the shitty steel that was available to Japan during the time period in which the sword was invented.",
"The “best tool” is very situational. When your enemy is armed with thick plates, your average long sword won’t quite to the trick, so you or a friend can step in with a mace to bust some kneecaps. Not only is it situational, but it’s also regional (in case you haven’t noticed). Some of the weapons like the polearms are more effective in larger ranks, where lines of soldiers can form a wall of pikes that make it pretty hard for anyone with a weapon shorter than 5 feet to get even close. It’s not the best explanation in the world, but the gist of it is that sometimes a situation will call for a certain weapon. Definitely something to look into in your free time.",
"There is not one weapon which is best. Think of the game \"rock, paper, scissors\". There are no superior choice. All of them are equal. And it is the same with weapons and armor. Sometimes you would have as little as three different \"best\" weapons that you expect to find on a battlefield but very often there would be a lot more different weapons. Soldiers would even be expected to carry multiple types of weapons so they could switch depending on what opposition they met. Then you have the issues of actually getting the weapons to the battlefield. Different weapons require different technology, different costs and require different amount of training. As technology and civilization have changed the types of weapons which are best have also changed. These changes have also had a huge effect on the rest of society. Sometimes a small force of highly trained and equipped elite have been the best way to form an army and other times large masses of untrained soldiers equipped with cheap weapons have been best. It all depends on what technology have been available, not only weapons but also armor and tactics.",
"It probably boils down to resource availability, utilization and advancement. Places that had less ore had to make due with what they had resulting in thinner or shorter blades or use of wood for the body of the weapon like a spear where just the tip is metal. In terms of utilization not all people are built the same so while bigger people could easily wield broadswords which inflicted heavy damage smaller people relied on agility and defense so they had to use smaller swords in combination with a shield. As time goes on weapon smiths developed new techniques and utilized new materials so weapons became more refined while other became obsolete. The weapons you named aren’t all from the same era so some are more crude than others.",
"I don't want to repeat other posters too much here, but here's my 2 cents: Like others have said, different weapons work in different situations, and that's really the basis of the answer. If you're up against armour, a blunt weapon will be very effective. So will short spikes, like those you might see on the end of a polearm like a halberd. You can stab that down onto a knight laying on the ground and punch through the plate or mail, whereas a sword would probably just bend or be deflected. You'll see swords going up against armoured opponents in the movies, but a sword cannot slash its way through plate armour. You might be able to get a lucky stab in an unarmoured area like the armpit or back of the knee, but you should really reach for something like a flanged mace or warhammer. Axes aren't as graceful as swords, but they're still sharp and they're probably easier to learn how to use (this is probably debatable and I'm not trying to make a definitive argument), so if you need to train up a horde of men for a fight quickly, you might consider axes. They're also relatively cheap to make; swords were generally expensive weapons. Also, they're just useful as tools. Your weapon for battle is also the tool you use to cut wood and build your home with. Since armour itself was very expensive, many soldiers would fight in cloth and leather armour. This stuff is still pretty resilient to slashes from swords, but I imagine a thrust would get through no problem. If the opponent is totally unarmoured, then a sword is probably the way to go. Swords themselves have so many different designs but consider the short swords that the Roman Legion used. They're designed to be most useful when used in the large formations that the Romans fought in. They're dead simple thrusting weapons, intended to be used for stabbing straight forward (or used in a chopping motion) from behind the protection of a shield wall. Compare that against something like a katana which is meant to be kept in motion - not going to work when you've got buddies on either side of you. And then we can consider the pure psychological aspect of certain weapons - some of them would make you shit your pants to go up against, and that's effective. In the warfare of hundreds of years ago, the killing is up close and personal and I doubt many of us would stand and fight against a 6'7 Scottish warrior who just decapitated a horse with a 6' long, two-handed claymore. You don't want to imagine yourself laying on your back in the mud with the maul hammer that just turned your shield to splinters then coming down on your ribcage. Samurai had spooky armour - this stuff matters. If I can scare my enemy away without drawing blood, that's a win in my book. You'll find some crazy looking weapons out there, especially some of the stuff from Africa that lean heavily into the intimidation factor.",
"Just like today, weapons have always been an arms race. Think about it this way. Let's say I'm going to war and I want to kill someone. Any old tool will work really. It doesn't take much to stab, bludgeon or hack someone to death. Which people tend to not like so much so they start bringing a shield. That's awkward, now you have a shield to deal with. Let's changed up my weapon a bit. [This is called a bearded axe]( URL_2 ). See how the axe blade droops down? That creates a hook I can use to hook someone's shield and pull it aside. [A flail uses weights on a chain so when I swing, the chains will loop right over the shield and smack someone in the nogging.]( URL_1 ) There are lots of ways to deal with shields really but they did cause weapons to change. So let's say the other person starts wearing chainmail to protect himself. Chainmail is quite effective at deflecting slashes but not so much at dealing with piercing damage. [This is a rondel dagger.]( URL_3 ) It has no cutting edges but it's basically a tapering spike designed to punch through chainmail. If you're expecting chainmail, you can start putting spikes everywhere,[like on this battleaxe]( URL_0 ). you can simply reverse it and use the spike. Eventually, people start wearing plate armour, which is even harder to get through. Instead of trying to pierce plate, heavy mauls and hammers can be used to crush flesh and bone inside. But very heavy weapons are slow and tiring to use. It doesn't take long before people realise that you really don't need that much weight. [Warhammers are pretty small things]( URL_5 ) but they're sufficient to punch a hole straight through armour. Note the spike on the other end for chainmail and hooking shields. We've found plenty of skulls with neat square holes in them. Anyway, the point is that weapons are designed with a purpose. And there are many different purposes. Cavalary sabres for instance are thin and relatively short but have curved blades. This gives them a very long edge for their size so that horsemen can let the speed of their horse and the curve of their blade cause terrible slashing wounds without putting any strength in their swing or hacking deeply and getting their blade stuck. Polearms have always been popular because they're cheap to produce and easy to train in. A pole arm is just a long shaft of wood with a bit of metal at the end, that's a very economic weapon. And it's not hard to train people to stand in place and point that way. The earliest pole arms were just sharpened sticks, and later on peasants conscripted for war would just mount the tools of their trade like farmer's tools and butcher's cleavers on the end of a pole when they went to war. Those developed into some really effective polearms. [If you look at these polearms, many combine a piercing spear tip, a hacking axe blade and a hook f]( URL_4 )or pulling horsemen off their mount. Others not depicted here would combine a hammer with a spike and a blade. By the 17th century, pikemen with enormous pikes had become one of the most popular types of soldiers. They were so unassailable that when two blocks of pikemen met, the regiment with the longer pikes would often cause a slaughter. Those enormous two-handed swords that were taller than a man weren't used for sword fighting. Swordsmen with those swords would be marching with those pike blocks and use those enormous swords to step out and hack off the shafts of the enemy pikes. They were named dopple soldner (double soldier) because their job was so dangerous they got double pay. Anyway, I could go on and on but there are so many weapons because they all have very specific purposes. On top of that, many simply arose from very specific limitations. Pole arms have a long history because they're cheap to make and easy to train. You see axes a lot, especially in the earlier centuries because they are very multifunctional and cheap to make. People already worked a lot with axes so they made easy weapons and easily developed into dedicated weapons that weren't also tools. In many places limitations were placed on who could own weapons and which weapons were permissible. A lot of Asian weapons are repurposed peasant tools. A lot of those exotic looking martial arts weapons are really repurposed farming implements so peasants could train with what they were allowed to have. There are a lot of very large knifes that arose when swords were not allowed and people just designed weapons that were right up against the limits of the law."
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"https://www.fabri-armorum.com/wp-content/uploads/2016/11/rondel-dagger-deco.jpg",
"https://i.pinimg.com/originals/e4/b6/38/e4b638238d558b5f9dd49fd52cfb0349.jpg",
"https://lh3.googleusercontent.com/proxy/TfpqbRjdiyBx7Xun7PW6_vwAwM0Vw-rj0PvAjawTQ2HANxD1PnOAm847AFA9BvmIw-RbpxFIeOrS4svpFRHy91Y_qhVzO4Qt5s7ETbusvr0xa-97on-8qcXtYrY5N5syrOH1mS1zVSgXGi917-PZ1AtGvdEbZqgvkIuAomYEX7we4WwjTWVke9LzkmdRfFILQbCVi1I"
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k1m4rg | Why do internet and email scammers intentionally misspell things or not use spell check? Isn’t that a dead giveaway? | End of question | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"That’s actually intentional! If a person sees those spelling errors, they aren’t going to waste their time sending an email or calling, they’ll just ignore the scam. If someone doesn’t notice the spelling errors, it’s much more likely that they’re less educated or that they don’t notice red flags. Which means that anyone who actually responds to the scam is more likely to fall for it. Less wasted time on people who are more likely to catch on and run.",
"For most of them, English isn’t their first language. That’s usually common in the 419 Nigerian scam messages. Some of the misspellings are also deliberate to evade spam blockers. If the spam blockers are looking for something like “get a bigger penis now!” you can try “mke yr peeenus bigggr nowww!”. A lot of spam these days comes with a bunch of nonsense in the text but the “content” of the message is in an image file and they’re hoping that your mail client auto displays instead of the garbage text.",
"It selects for uneducated, very old, senile, or otherwise intellectually disabled people. They are much easier to scam. People that notice those errors and disregard the email are not the target audience."
],
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