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f5arcn | What stops a computer game from cheating when you play against the computer? | Technology | explainlikeimfive | {
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"Literally nothing. A game developer could make their AI as cheaty as possible, since it's part of the game's code itself. Of course, to make a fun and fair game, you would want the AI to follow the rules, lol.",
"The person(s) that made the game stops the game cheating, or inversely makes the game cheat. The game won't do anything it is not programmed to do, it is a slave to it's programming. A computer won't suddenly decide to cheat just because it's losing, it will only cheat when told to cheat. Games don't have a legal requirement to be fair, and sometimes fair is boring. If a game designer thinks that having the computer cheat makes for a more entertaining experience for the player then there is nothing physically stopping him from programming the game to cheat.",
"The programmers who design the AI purposefully program if and how much it cheats. If they make the AI use its perfect knowledge to always beat the player, the game is no fun when the players realize it is impossible to win. So the programmers purposefully limit the AI. If there's some kind of fog of war or unknown area, they can program it to only use what it would see if it were a player. If accuracy is part of the game, they'll add a randomizer which can purposefully make a percentage of shots inaccurate. If a game with turns, it will only be able to look ahead a certain number of moves. Some games do allow the AI to cheat to some degree though, but it's usually some setting you the player can choose if you want to make the game harder. But in general a well-designed game will never have the AI be so good that it can't be defeated.",
"The developer. Most AIs cheat by default, like using \"map hacks\" and such but their behavior is dumbed down based on difficulty. Reason is because it's easier to program with the AI sees all instead of having to constantly adjust based on feedback loops.",
"The game programmers want their game to be fun. If they let the game cheat it would just be frustrating.",
"Often, the game actually *does* cheat when you play against the computer. It does this to simulate difficulty, since an AI cannot make as advanced or unpredictable moves as a real person. For example, the bots in Overwatch basically have an aimbot. AIs are cheating by default, but the programmers write extra code to simulate stupidity so that they aren't always winning. For example, in League of Legends, the AI opponents leave time between using abilities and making attacks, when a real player would use their abilities in much faster succession.",
"Because they are not programmed to? The \"AI\" in traditional computer games is actually not an AI but just a lot of 'if this do that'. They aren't sentient or anything, so if there is no 'if losing badly, cheat' programmed in they won't. As far as I remember StarCraft II actually had some difficulty levels where the computer actively cheats. The programmers gave them full vision of the map at all times meaning there is much more information to base the next move on. But these next moves are based on complex sets of algorithms, not a sentient AI."
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f5ewo8 | How do MRI mechanics work | Technology | explainlikeimfive | {
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"MRI works by taking advantage of the magnetic properties of hydrogen, an atom that is present throughout the body. The way it works is that in a hydrogen atom is constantly rotating around its principal axis. This rotation creates a magnetic field. Normally, the principle axis of all the hydrogen atoms in your body are sort of randomly distributed, since Earth's magnetic field is not strong enough to affect them. An MRI scanner will create a very powerful magnetic field, up to 1500 times stronger than Earth's. When you are inside this very strong magnetic field, most of the hydrogen in your body will become aligned with the magnetic field generate by the MRI machine. Radio waves are then passed through the region of interest. Radio waves have a little bit of energy in them, and the hydrogen atoms will absorb some of this energy and their orientation will be slightly changed. When the radio waves are turned off, the hydrogens realign with the magnetic field, and this synchronized rebound will give off a energy that is measured by detectors. If you measure signals throughout the area you're looking at, MRI can create an image based on the distribution of hydrogen in the body. The areas with the most hydrogen atoms are typically the watery bits of the body, so you can clearly see different types of tissue."
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f5ikil | what does it mean when an iPhone has a panic or a kernel panic? | Technology | explainlikeimfive | {
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"A \"kernel panic\" is a term used in Unix-like systems to signal encountering an error by the operating system from which it cannot gracefully recover. Computer programs are extremely complex logical sequences of operations and it can come about that a logical operation is attempted that cannot be completed. For example you might have a computer trying to divide a number by zero; this shouldn't ever be attempted because it cannot be done, but when things go wrong a program might be directed to try without any other option to resolve the situation. In a kernel panic event the operating system runs into a problem it cannot resolve and fails, usually dumping its memory contents for bug analysis and shutting down.",
"Operating systems do a number of things but largely their most important role is to provide an environment in which multiple processes can run simultaneously. The operating system arranges various programs to run seemingly at the same time, having them share various resources, most importantly the CPU, which is shared by having each program get a few microseconds of computation from the CPU before that goes to another program. The kernel is the core of the operating system. When a program decides \"I don't need any more CPU for now,\" it gives control of the CPU back to the kernel so that the kernel can give it to another running program or do whatever it needs to do. When a program needs to get stuff from the internet, it asks the kernel to get it for it. When the program needs to access a file, it asks the operating system to get it for it, in the process checking if the program is allowed to even access this file. A kernel panic happens when the kernel does something wrong, say divide by zero. Generally if an individual program does something illegal like this, control is returned to the kernel who decides what to do based on what it was programmed to do, generally this involves killing the program. It used to be that if a program did something wrong like this it would bring down the kernel too but we have gotten quite good at avoiding such situations. The issue lies in the kernel doing something bad. If the kernel does something bad like divide by zero, this means the programmer who made the kernel messed up firstly, but also means that there is no real way to recover from it. If your future calculations rely on this division working but you divided by zero, then your future calculations don't really make sense. So it is programmed to crash. It tells the user something went wrong in the kernel panic screen (also in windows known as the Blue Screen of Death) and shuts itself down."
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f5kxl2 | Why are random distorted codes used as a safeguard for entering information to websites? | Normally seen when you’re buying something really popular, and often seen with a mash of ‘Xh38bF’ that looks all swirly and weird. | Technology | explainlikeimfive | {
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"Are you talking about captchas? These are used to make sure you're a human and not an automated service. Humans are great at recognizing general shapes from pictures, but it's really hard for a robot to pull meaningful information from pictures. They're getting better at it, which is why you'll see more and more other tests, but it prevents Any low quality or cheap automated programs from using whatever it is.",
"So the previous two answers are correct, but I will go into a bit more detail. The reason that “swirly codes” provide security is because there are a huge number of “bots” roaming the internet. These bots are essentially a program, and have no actual person controlling them. Just like most things in the world, there are good types, and bad types of bots. An example of a good bot would be a bot from Google, that is used to gather basic information about webpages. Because of the massive amount of webpages that exist, google can’t possibly analyze them all by hand, so they created programs to do it for them. However, it’s the bad bots that we need to worry about. I work for a large company in the IT department. Our main webpage gets over 1,000,000 login attempts per day from bots. These bots are all trying to take advantage of a customer by getting into your account. Now, the front line of defense is obviously your username and password. But if the bot somehow has that password, the “swirly words” keep it from being able to log in, as bots are very bad at matching things, while humans can do it with almost no trouble. While bots can be trained to match things, it is a very very long and complicated process, where you have to show it millions of photos of that particular thing, and tell it what it is. It’s then able to use AI to spot things that are similar. However, the amount of time and effort it takes to get an AI to that point is immense, and not something that even an above average hacker could easily do. This is why you don’t see millions of people’s accounts getting hacked whenever a massive data-breach happens. Instead of coding a script to use all that data at once, it must be done manually, by an actual person, all thanks to the swirly letters. Hope this helps!",
"Bots can't easily decipher those. Not as easily as us humans anyway. It keeps the site from being invaded by an army of bots."
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f5nx60 | Why does a debit card reader ask what kind of debit card you are using? It cancels the transaction if the wrong answer is given, so does that not mean it can tell what kind it is? | Oof, I suppose it's a little late to clarify this post. I didn't expect it to get any attention and at this point my question was sufficiently answered, but for clarity's sake, the specific scenario I was referring to was this: I am in the USA. I go to pay for a movie ticket with my VISA debit card. I insert the chip and the card reader asks me "VISA Debit" or "US Debit." I accidentally select "US Debit" and the transaction immediately cancels. I try again, selecting the correct option, and the transaction processes normally. I was confused about why it needed to ask, considering it seemed to have the technology to figure out which one it was. I apologize for the vagueries in my original statement. ELI5 wouldn't let me post a more specific title. | Technology | explainlikeimfive | {
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"US checking in. I get prompted for Credit or Debit on my card. Both go through. Credit and Debit transactions are handled by completely different systems. The differences: If you select the Credit option, the transaction is processed through Visa, Mastercard, or another major credit card brand as if it were a regular credit card (as in, a card with a revolving line of credit which is not attached to a bank account). The merchant doesn't know that this is a bank card and not a credit card. They get their money and pay a 1.5% - 3% fee on the transaction. The transaction is also subject to consumer protections regarding credit cards; the consumer is never liable for any more than $50 (every bank goes over and beyond by making the liability $0, even though they don't have to.) If you select the Debit option the terminal is now an ATM and the transaction is handled by a debit processor (the logo is on the back of the card, examples include Star, Pulse, Nyce, Accel, and Maestro). It's treated as a debit withdrawal like if you were at an ATM (though, nowadays, the actual transaction is coded in a way that the bank knows that it's a retail transaction and not an ATM withdrawal). The merchant knows it's a bank card. They get their money and pay a 0.25% - 1.5% fee on the transaction. The big differences here: Credit: * Accepted just about everywhere. * Transaction fee is more expensive for the merchant. * The money may not be debited from your account for a day or two in some cases. * Consumer protection laws exist. * May or may not be secured with a PIN (this is up to the bank and the retailer in the US). * Does not allow 'Cash Back' transactions. (This is a policy thing. Some merchants can just manually charge a larger amount and hand you the difference.) * My bank lets me accrue points on Credit transactions. Debit: * Accepted in a many places but certainly not the level of ubiquity you see with Credit. * Transaction fee is cheaper for the merchant. * The money is immediately debited from your account at the time of the purchase. Debit holds for pre-authorized fuel purchases last only minutes, not days as with credit. * The consumer protection laws on debit transactions are minimal. Most banks will protect you but, to be clear, they are not required to by law. * Always secured with a PIN. The debit protocol requires a PIN for every transaction, no exceptions. * Generally allows cash-back as an option on the terminal. The merchant is allowed to turn this feature off. * My bank does NOT let me accrue points on Debit transactions. Edit: In my attempt at being a know-it-all, it seems like I latched onto the wrong part of the post. As far as my attempt at answering as to why it's necessary to prompt for the type of transaction rather than asking the card about the transaction, I don't know the answer. My working theory, however, and this is just speculation, is that the card doesn't indicate what types of transactions are supported. If you attempt to run the wrong type of transaction, the transaction is declined and a transaction fee is accrued by the mechant. The next best thing to do is ask what type of transaction to try before attempting to run it. Some banks DO use a standardized subset of card number prefixes exclusively for debit. (This is the first four numbers of the card number.) This is how some terminals can figure out that a card has debit transaction capability.",
"In the UK it doesn't ask. Abroad it takes a while to get used to the options... Checking, savings, current... Sometimes it's not hugely clear.",
"Wow nobody here has understood your question. On most Verifone Mx915s I install on Buypass generic payment networks, when you insert your debit card It will prompt you to select Visa Debit or US Debit. US Debit is normaly what must be selected just because It cost less for the merchant to prosess it. Generally on generic sites thoes settings can be changed in the Commander. Cant say ive ever seen it prompt the Debit question on a Gilbarco Passport POS system.",
"In Australia you can link the chq and sav options to a different bank account. This goes through as a normal eftpos transaction and disappears from you account immediately. Most merchants don’t get charged for eftpos transaction as it’s included in their monthly merchant fee. If you have a credit card (ie a line of credit from the bank so that you owe the money) then this is linked to the Credit option. These transactions got through MasterCard, Visa, Diners & American Express and the merchant gets charged a few % by the these companies. This is the way they make their money from to cover unauthorised transactions, loyalty points and fraud (to be fair they also get it from the up to 27% interest they can charge the card holder if they don’t pay on time) Credit cards have the standard 16 digit number, expiration date, CCV (3 numbers in the back) and in recent years the rfid chips that allow you to tap and pay amounts under $100 without a pin. They are also what’s used for online purchases. Many consumers prefer to use credit cards to get something now but pay for it at the end of the month (and get loyalty points). Merchants don’t like it as much as they get slugged a few % that eats into their profits. Consumers also like the tap and go feature for low value amounts to get in and out faster (and can dispute transactions) In recent years banks have started offering debit MasterCard and debit Visa cards. These have the advantage of credit cards however use your money straight away and you can’t owe the bank anything. The banks love this as it means they are making money off transactions that used to be chq or sav types; and consumers like it for the ease and features of a credit card. Merchants however still get slugged the credit card merchant fee; and the banks don’t have to run a loyalty program (so they make more per transaction) Terminals themselves are only built by a couple of vendors worldwide and as such they have to program them to work in different markets. Transactions rules in the US are different to the UK which is different to Australia, India, China etc. (actually to be fair banks can customise the terminal firmware for their own requirements however the underlying software is still the same). Firmware updates to terminals in Australia are typically released every 6 months to fix bugs, add features etc. In terms of the card and the terminal knowing which account you want; the reality is they they don’t. When you insert your card a hidden serial number of that card along with the transaction type (chq, sav, credit), a PIN number (if entered), the merchants terminal ID, date/time are all encrypted and sent to the bank. The bank checks the details; looks up your PIN number it has on file, checks if you have enough money and then responds back to the terminal yes or no. If you press an account type that is not linked to your card then it still has to send the signal to the bank to check to see if there is an account there. (The card doesn’t know) There is probably more but that’s a quick 101 for Australia. Source: I install and manage terminals for many Australian Banks and currently have about 150 terminals in front of me that need reprogramming.",
"I have never seen this happen. I have only seen combined readers that will handle Visa/Mastercard/AmEx/Visa Debit without asking which type you are using. When Switch/Solo were around, those were likewise autodetected. Contactless, just the same. Visa/Mastercard/Visa Debit/Apple/Android/Samsung Pay, just works without having to specify. Oyster pads, even more of the same. It just works. & #x200B; When you put your card in, it may flash up on screen what type of card you have put in when it gets you to confirm the value and enter your PIN.",
"What do you mean by “type” of debit card in this regard?. The reader knows everything about the card from its number and data on the chip/strip. Are you asking why does it ask credit or debit?",
"I'd guess it works like this: 1. The machine needs to specify the type of transaction, but does not know the type of card (either due to being based on an older machine, or because some cards allow both ways). 2. Obviously, the machine should not just choose one, so it asks you. 3. The machine sends the request, and gets \"no\" for an answer. 4. The machine refuses the transaction. It might know the reason from the refusal, but due to security concerns or laziness (aka reduced cost), it might not tell you.",
"The probable answer is that you're in a country where some cards have multiple accounts on them. In New Zealand for instance you might have a cheque (current account), savings and/or credit account all on one card. When you make a card payment the machine is asking you which account you want to make the payment from and if you have multiple accounts you get to choose. In the UK we don't have this, instead we have one card for each account. So even if you have multiple accounts at the same bank, you will have an individual card for each of those and the machine doesn't need to ask you what account you want to use to do the transaction. The reason it fails, on machines that check, is because if you choose the wrong one and your card/provider doesn't support it then the final communication with the bank/credit card company fails. The machine probably just doesn't bother checking before this final communication. This is probably to reduce the number of communications (e.g. Web requests) that happen, or it could be something more complicated about encryption and encryption keys that mean things have to be completed in this specific order.",
"I'm not sure how it works in the US, but in Singapore, there are 3 major types of card: your usual Visa/MasterCard, NETS, and CEPAS. They all operate on the same frequency, but have different decoding and security protocols. A typical reader can't tell at first glance what card you're using, but it can tell you're using the wrong type of card. When you select a type of card, the reader initiates the corresponding communication protocol. The reader pulses EM waves at the card, and in response, the chip will pulse back a corresponding message. If the reader tries to decode this response message and only finds garbage, it knows you're using the wrong card. Real ELI5: You (a card) want to access a high security building (a reader). To get in, you need to answer a set of security questions. At the gate, you choose what language you want to speak, and then the building sends out a guard who speaks that language, and only that language (the software communication protocol), to ask you the questions. Now if you choose Spanish at the gate, the Spanish speaking guard comes and ask questions, but you respond in French, then he wouldn't understand you, and you fail the check. The guard doesn't know you're speaking French to him, he only knows that you're NOT speaking Spanish.",
"I am surprised no one has mentioned accounting software yet. The reason WE ask is not for the POS machine (the machine your card gets put into) but for our accounting/billing software. We are a SMALL retail operation and the 2 systems are not linked, so we need to specify in a drop down menu in the invoice what type of payment the bookkeeper will be looking for when she reconciles the month. The payments show up in the bank account different due to the way we pay for your transactions (25cents per debit, 1.9% for cc) This was true at my last job (simply accounting), when we opened our business (Sage50), and afternoon we switched systems (Wave).",
"They can tell, kind of. But asking to make sure saves money if they get it wrong. Debit is authorized on a separate network than credit. So if you shoot one up the wrong pipe, you waste time and money. Back in the 90’s the banks used to do “convertible” debit. If you shot a debit up the credit pipe, they’d convert it for you, for a hefty fee to the retailer. The trick was, they refused to tell the retailer which cards were which. The retailers did the whole class action thing, and won. So the providers released the “bin ranges” of which cards were which. Early on, the debit readers and registers couldn’t fit all the bin ranges for the country, so you’d get asked a lot more “debit or credit” if you traveled or had a weird card. Bottom line, if you want to dork retailers, convert to credit.",
"In the U.S., many payment cards linked to your bank accounts (e.g. an “ATM card” or “check card” or “debit card,” as opposed to a ”credit card” or “charge card”) have dual functions. They can work BOTH as a “debit card” and a “credit card.” So it does in many cases actually need to ask you how you’d like the transaction processed. Debit payments and credit payments use different networks and have different economics. With a debit payment, the retailer pays basically nothing. With a credit payment, the bank gets a cut of the transaction. Naturally banks had an incentive to push the ability to use their cards on the Visa or Mastercard networks. Beyond that, Visa and Mastercard were accepted more universally than debit cards (particularly since there are multiple different debit card networks that aren’t always interoperable) and was “easier” given credit cards in the US until recently only needed signatures (versus debit cards needing PINs). Also, the “Debit” networks are more Balkanized and less visible. TYME, STAR, NYCE, Pulse, Allpoint, Moneypass, etc. Used to be even more fragmented.",
"When you scan the card (or type in the number, tap it, whatever), that transaction first goes through the \\*payment gateway\\* (example: [ URL_0 ](https:// URL_0 )), which handles things like \"is all the data present, is the date in the right format, do we have a phone number\" etc; then it formats and encrypts the transaction to be sent to a \\*payment processor\\*, which does a few other things, and then sends it either to the \\*Interchange\\* (mixed network of Visa, MasterCard, Discover, etc - basically an \"input pool\") or the American Express IC (Amex is not part of the Big 3 Interchange). Finally, the transaction gets to the actual credit card company (i.e. specifically Visa or Amex). There are rules set by the individual credit card companies; rules set by the interchange; rules set by the payment processors; rules set by the payment gateway; and finally, the individual merchants may have the capacity to add their own restrictions or conditions. So, while the system may indeed be able to tell what kind of card it is, one of the 4 or 5 layers may have a \"trigger\" in there that will reject that particular combination of inputs. And yes, they can tell exactly what card it is, including whether it's a rewards card, miles card, platinum/preferred/etc. Each type of card may have a different transaction fee (who do you think pays for all those cashbacks and bonus miles? It's not Visa or Discover doing it out of the goodness of their hearts, it's the merchants paying an additional percentage on each transaction) - so sometimes merchants may elect to block certain types of cards, because they'd much rather pay 0.1% for a no-bonus debit (no risk) card, than a 3.2% for a cash-back gold credit (risk) card."
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f5o90c | How Vsync Works/What It Is/What It Does. | Technology | explainlikeimfive | {
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"Vsync matches fps to screen refresh rate, or in case of adaptive sync matches screen to fps. Some games tie their physics to framerate. For example Dark Souls 2 durability bug: game was designed for 30 fps, and the physics were tied for that. When the game was released with 60fps on Pc, most of it ran great, except for durability on weapons. Durability degradation was tied to frames, not seconds. Say, you strike an enemy and the weapon loses 1 point of durability per 2 frames of colliding with the enemy. Now because the durability was tied to 30 fps, on consoles it was working as intended. But on Pc with 60fps the game was still tied to 30fps, and thought the collision lasted not 2, but 4 frames and the weapon degraded twice as fast. That is also the reason rolling needed to be more precise on Pc, the invincibility window was measured in frames. In Dead Space's case, physics are tied to frame count, not internal clock of machine (console or pc). And ingame Vsync is kinda wonky, sometimes resulting in incorrect frame counting and physics breaking down. For more info you'll need to search the game engine analysis, but iirc my explanation is enough to get the gist of it.",
"What VSync does is match the fps of the game with the refreshing rate of the monitor. Most monitors have a refreshing rate of about 60hz, meaning they update the screen with a new image about 60 times per second. If you activate vsync, your game will lock the fps rate to match the monitor's rate, in this case 60hz, meaning the game will be locked at 60fps and never going higher than that (but it can go lower if you don't have enough hardware to run the game at 60 or above). In the case of the video, it's most likely a bug and has nothing to do with how VSync works."
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f5qqp0 | How do we know that a technology is "ahead of it's time" by X many years? | Technology | explainlikeimfive | {
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"You're being too literal. It just means \"no other company doing this is expected to have an XYZ for another six years or so\"."
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f616iq | How do satellites measure ocean salinity? | [ URL_0 ]( URL_0 ) | Technology | explainlikeimfive | {
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"Salinity changes how water reflects microwaves. Satellites can capture the reflection of microwaves, so some math, and figure out how much different the area they’re looking at compares to pure water."
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f69uhe | why do modern video games require installation on console? | Technology | explainlikeimfive | {
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"With the older consoles, the game loaded all the files it needed from the disk into memory each time you started the game and loaded a level. This had the advantage that consoles didn't need a big internal storage, which was fairly expensive back then. The PS2 just needed a small flash memory stick to store save games. However, the big problem with that was that games could not be changed after release without shipping new disks. So any bug that was found after release of the game would stay in the game forever. The same was true for the console itself: They weren't able to fix any bugs or vulnerabilities of the system itself without releasing a new version of the console. The 360 and PS3 both came with built-in storage. This allowed them to download updates for the console and the games. However games were still designed to be able to run on consoles with just a small amount of hard drive space, so you could just pop in a disk and play a game without waiting for an installer. Even if they did need an update, it had to be a small file size so it was quick to download. The newer consoles now have a very large amount of local storage, just like PCs. Developers use that to store all the game files on the much quicker hard drive instead of reading it from the slow optical drive, which speeds up loading times. It also allows them to ship big updates, often including the dreaded \"day-1 patches\": That means they intentionally put an unfinished game on the disk, so they can use the time between printing physical copies and actual release of the game to finish development. For the user, that means the first time they launch the game, they have to connect to the internet to download a patch.",
"Because games have gotten much bigger and it's far easier to just either compress them on physical media or have people download the game files and then get them put on the machine's hard drive. Like, RDR2 is 150 GB. That's 6 blu ray disks. This leaves aside that reading a data off a disk is slow and produces wear on the drive.",
"Those discs have limited capacity and read speed. A BluRay discs can be read at 36 Mb/s. A typical hard drive (7200 RPM) has read speeds starting at 640 Mb/s. Solid state drives are even faster. So if you are not willing to wait for your AAA game to load for 5 min every time you start it or change maps, you will want to install it onto the hard/solid state drive in your console.",
"Literally nobody in the comments in mentioning the switch, with cartridges that load faster and hold as much info as a disc. Why doesn't ps5 do THAT?"
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f6aqae | What could stop foreign governments from intercepting and tampering with submarine Fiber cables ? | Technology | explainlikeimfive | {
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"text": [
"depth, access, expense, visibility. there are much more efficient ways to intercept/tamper, etc."
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f6hebp | how does a smartphone accelerometer (or a compass) work? | Technology | explainlikeimfive | {
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"It uses a technology called MEMS (Micro Electro-Mechanical Structure) which consists of tiny fingers of metal inside a computer chip. as the phone shakes and accelerates, these fingers get 'pushed back in their seat' so to speak, which brings them closer to other fingers. This causes a change of capacitance which is registered by the computer as an accelleration",
"The accelerometer and gyroscope involve incredibly tiny components which are able to bend. When the accelerometer is moved, a weight in the center lags behind and bends some arms. This bending and movement is detected as acceleration. Meanwhile, several tiny arms are vibrating. As the phone is rotated, their vibration remains in the same direction and so the phone feels like they vibrate in a new direction and this information tells it how much it has rotated. There is also a magnetometer that can measure the strength and direction of local magnetism. This works based on how electric currents are deflected by magnetism."
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f6l3fz | How does a password reset link know to log you in and change your password? | Technology | explainlikeimfive | {
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"When you initiate a password reset request the server will generate a unique temporary token (a short string of letters and numbers) that will be included in the link it emails to you and save it somewhere related to your profile for later. When you click the link the site will then check to make sure the value in the link matches the value it has stored to confirm that the person viewing the password reset page is in fact the person who has control over the email address you have on file."
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f6odph | How are subtitles detected for live events like sports or award shows? | I’m watching a hockey game in a bar and it said “knocked the fuck off his stick” obviously was supposed to be “puck” but funny nonetheless. | Technology | explainlikeimfive | {
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"They are done by a stenographer typing it out as they hear it. Just like stenographers in court, they have special keyboards that allow them to type as fast as people talk, but with live broadcasts they sometimes make mistakes and just simply don’t have the time to fix them."
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f6oeg8 | Airdrop data transfer | Why can I Airdrop a large file, but wouldn’t be able to send that same file by text message or email? | Technology | explainlikeimfive | {
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"Airdrop is a direct file transfer between two devices over WiFi or bluetooth. If you try to send the same file via email or text message, the file will have to be sent out to a server and then to the recipient. This has additional bandwidth and storage costs that will add up quickly across large numbers of users for whoever owns the email/text server.",
"AirDrop uses Bluetooth and WiFi in a pretty smart way. Your phone acts like a walkie talkie with Bluetooth by sending a “hello” message out to anyone nearby and will only listen back from people in your contact list (unless you specify everyone). Then once you have figured out the person on the other end you want to send to, it creates an ad-hoc WiFi connection between you both, meaning it doesn’t require you both to be connected to the same WiFi access point; it creates its own temporary one with encryption specifically for the file transfer. Because of this you can transfer large files due to only being restricted by the speeds of the WiFi chip on either device.",
"Airdrop allows your devices to talk directly to each other using Bluetooth and WiFi. This cuts out any data limits or slowness created by sending data through someone else’s much bigger, more complicated network. The downside is that you are limited to using airdrop only when two devices are close enough to connect directly to each other without a bigger network to help."
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f6swoy | _ 5G / Frequencies / Spectrum | I just don’t get it... it’s supposed to be waves right? Of different length? Then how come the governments are offering different ranges but they are all still 5G? Please help... | Technology | explainlikeimfive | {
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"ELI5: Imagine Radio waves as colours. You have many different colours, and you can see the difference between them. 5G is specified as using all the different shades of blue. You can't have all operators use the same colour, because then how would you know who it belongs to? So what the government does is sell a specific shade of blue (let's say navy) to Operator A. Operator A can now use navy without having to fear getting their signals mixed up with the teal-coloured signals from Operator B. ELI am older than 5: 5G is just the standard on _how_ the information gets sent. The exact frequency is not relevant. So in order to protect against interference every tower/operator uses a frequency slightly offset from 5GHz",
"Recently went to a technical conference on this so perhaps I can provide some insight: First things first, the term \"5g\" is grossly overutilized and means different things depending on who the source is. If you're hearing it from *any* wireless carrier, you are more than likely being misinformed - with some variance between carriers about who is lying the most. eg: ATT started calling LTE carrier aggregation '5ge' - this is the most bold faced lie. Tmobile and verizon are calling their > 29ghz high throughput cellular connections - this is less of a lie but still \"not the case\" the 5g standard is really more than anything software virtualization in the cellular sphere, and it changes the way network operators (carriers) share and utilize spectrum. In the old days, and still currently, carriers would buy frequency blocks in different parts of the country and if not roaming, your phone would connect to them. eg: tmobile and verizon have a lot of 700-750mhz towers, ATT has a lot of 1900 mhz towers, and there was very little crossover between the two excepting roaming agreements. 5g wants to upend this schema in the name of frequency efficiency - so the proposed solution is that all carriers \"share\" frequency and distribute it in a load balanced manner to all customers in that area. So lets go back to the whole ATT/Tmobile thing. When 5g is activated, your phone will no longer connect to an \"ATT tower\" it will connect to any tower and you will have what is known as a \"Virtual Socket.\" The cool thing about this is, using this tech combined with our phones multiple antennas, you can have multiple virtual sockets at various frequencies depending on your bandwidth needs. So again - instead of having a huge pipe to one frequency block, you will have smaller pipes to many frequency blocks. It needs to be stated that *no carriers* in the US have implemented this, as far as I know the only country really making any headway here is china. Anyway - this is what 5g actually is. Now what you're talking about are new radios to expand the capacity of network carriers for the purpose of 5g, but not actually 5g itself. The physics of wave propagation dictate that the higher the frequency of a signal, the higher the path loss over distance - so generally speaking, lower frequency signals (600-700mhz) can penetrate buildings and propagate further than higher frequency signals (1900-2400). new cellular radios are trying to utilize 29000 mhz frequencies are higher - and this is challenging because the path loss is so great. Which is why you are hearing talks of blanketing entire cities in antennas - its the only way to make these > 29ghz frequencies usable for data transmission. (fun fact, 6g will make it so every handset and connected device acts as a transceiver for a gigantic mesh network) so TLDR / ELI5: 5g is a software standard that allows carriers to send you some 700, some 1900, and some 29000 seamlessly to maintain your connection rather than one fat pipe of 700, 1900, or 29000. Everything else you hear about is just technology meant to make 5g better. PS - the reason we like higher frequency blocks is there are very few devices that utilize it and thus there is more \"room\" for data transmission. You also see this in Wifi: 2.4ghz is not really any worse than 5ghz for data transmission, but there are way way way more things that aoperate at 2.4 and the available spectrum is smaller. 2.4 operates from 2402 to 2482-ish. only 80mhz of \"pipe\" to work with. 5ghz operates from 5000mhz to 5800mz. Way more \"pipe\" to work with - so even though 5ghz has greater path loss, it has much more availability to do some tricks to alleviate that. the 29ghz stuff has 4000-5000mhz available for the pipe."
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f6wmsd | What is FXAA Antialiasing and what does it do for PC Gaming? | Technology | explainlikeimfive | {
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"**F**ast Appro**x**imate **A**nti-**A**liasing. It smooths out jagged edges in rendered animation/screens. It's also faster than some other methods and uses less CPU because it only smooths out edges as they appear on screen, not how they are actually rendered. It can also work on non-vector based images unlike MSAA (multisample anti-aliasing). In games, it gives you a better image for less computational power which in turn means higher frame-rates."
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f73lln | Why are online "password lockers" considered secure? | It seems to me (hence this question), that storing all your passwords online and accessing them with a single "unlock" password would be extremely dangerous. If the locker service is itself hacked, then the hackers will have ALL your passwords for the price of getting one password. | Technology | explainlikeimfive | {
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"Your \"single password\" isn't just proof of identity the way it is on reddit. Your password collection is encrypted with your \"single password\" before being uploaded to the locker. It is mathematically impossible (unless some kind of breakthrough happens) to break it without knowing that master password. Even the password locker service doesn't know the master password and are just holding onto this blob of encrypted data for you. If the hacker breaks into the locker and gets all your encrypted passwords (and everyone else's for that matter) they still need to break through the master password in order to get the real data. That's why it's so important to select a good password. And in the grand scheme of a big leak, each user's master password must be attacked independently so a good master password means that you're probably safe unless you're being specifically targeted and get most of the hacker's password cracking resource as a breach of millions will spread their efforts too thin. If you use the method where you have a file saved to disk that is half your password, then even guessing passwords isn't enough for the bad guy because that's only half of it. ... But all this means that if you forget your master password, you're out of luck unless you took precautions beforehand. There is no recovery.",
"To put it in ELI5 terms: Imagine I tell you to think of a number but not tell me. Let’s say you pick 25. That is now your key (master password) and only you know it. When you need to give me a password to store, you first multiply the password by your master key and give me the end result. Let’s say you want to store the password “1234”. You would take 1234 and multiply it by the master key you chose (25) and get the result: 30,850. I will now store “30,850” on my server as the password. Any time you need to access that password, I will send you 30,850. Since you know your master key is 25, you do 30,850 ÷ 25 and presto: you now see the password is 1234. If a hacker were to break into my system and read your password, they would see the encrypted password 30,850. The only way for them to figure out the real password would be to know what your master key is. Of course real encryption uses infinitely more math and added complications like hashing and salting, but that’s the incredibly dumbed down version of the system, enough that a kid could get it.",
"Ideally, everyone has a high strength password for every account. But the thing is, everybody has tons and tons of accounts everywhere. There are just too many passwords for a human being to remember. This results in people using the same password in many places, or using easy to guess passwords, just so their ape brains can remember. And not all websites are good with their security. Some no name forum with a security scheme that hasn't been updated since 2008 might hold a password in plain text. This password being reused in a high security account. Stealing that password is easy and can be used to break into a stronger security account. The password locker prevents this kind of attack, by doing the remembering for you. They also presumably keep their security policies better than average. A hacker would find a much much harder target, though the rewards would be much higher. A human can also remember one password that is much stronger than you would normally put in a website.",
"What's the alternative? If you use the same password across multiple websites, then if *any* of those websites are hacked then your password could be compromised. Your password is only as strong as the weakest security amongst all the websites you use it on. So you need to make sure you use a unique password for every site, how do you keep track of that? Of course, keeping your password list entirely offline would be the most secure thing you can do, but at a certain point most people are willing to sacrifice some security for convenience. Good password storage services try to mitigate the risk as much as possible. - They should encrypt your password list with a master password that only you know - They should let you use 2 factor auth to mitigate someone stealing your master password - They should notify their customers immediately if there are any security breaches Ultimately it comes down to who you can trust more: the password storage service or the weakest of all the sites that you use to store your single common password.",
"A year or two ago lastpass got hacked so it has happened and everyone on the service had to go change their master password. Luckily they caught it fast. Ultimately people have a lot of credentials, which leave a few options. You can use the same password everywhere, but if one account gets hacked they have the password to all your accounts. If you don't do this they you are going to have a list of passwords. Online vaults are simply more secure then putting the password on a list on your computer, even if you encrypt your list, if the computer crashes you lose all your passwords. To simplify, there is no zero risk when it comes to credentials but the online secure vault is the least risk for disaster recovery and being compromised. Secure only means more secure than other options."
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f75g7o | Why is it that when you see a computer screen in a movie or on tv it doesn’t do that distorted thing that always happens when you see a computer screen in a video shot with a commercial video camera? | Technology | explainlikeimfive | {
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"Most screens in movies and TV shows are faked with CGI. They just replace the real screen with an image of whatever. Screen flickering is part of the reason, but it also solves issues with screen glare, the screen appearing dim, etc. It's just easier to put in fake screen in post-production than to deal with a real screen image.",
"Assuming you’re referring to “old” TVs and computer monitors...They have specialists with equipment that can play video on that screen at the same frame rate as the camera recording it. The issue is that the camera is picking up the vertical scan lines of the CRT monitor which are scanning at a different rate than the camera’s sensor. More info: URL_0",
"LGR made a video on how he records screens URL_0 Flickering is removed by adjusting the shutter speed to match the display. Can also be done by editing the final video. Moire pattern can be removed by having the display slightly out of focus, low pass filter or by just blurring it. Colors are also adjusted in video editor, reflections removed with polarizing filter and well placed lights.",
"It's actually a really simple answer. The screen in the movie has nothing on it, and instead is a mini green screen. They then add in the graphics during the post production process. It eliminates the effect that you described and also eliminates the problem of timing what is going on the screen with what the actors are doing."
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f77hvy | How do digital scales/microbalance work? | From what I read digital scales use load cells/strain gauges to detect force applied, but how does a load cell actually work under the circular metal plate that you see in digital scales? Is that metal plate/pan a special plate or is it just there to hold matter over the load cell? For more precise microbalances I also know that magnetic sensors are used. Can someone explain how magnets are used to read off pressure/force? Do the metal pans in microbalances also affect the magnetic sensors? | Technology | explainlikeimfive | {
"a_id": [
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"Strain is the technical name for when things change shape due to mechanical forces. So, a strain gauge type of load cell is usually just a piece of something conductive that will change shape slightly (ie strain) when a force is applied. The resistance of a conductive thing is related to the length and area of the thing. So when the conductive part of the load cell is subjected to a force, it changes shape slightly which changes the length and area, in turn changing resistance of the thing slightly. Hook up a known voltage across the conductive thing and the changes in resistance will cause the current flowing across the thing to change slightly. Hook a current meter into the circuit and you now have a numeric read out that varies in proportion with the weight placed on the cell. Calibrate it with some known weights and you're away."
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f796tc | What does the term "baking" or "baked in" mean in video game design? | Technology | explainlikeimfive | {
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"When something is described as \"baked in\", that means it is fundamentally part of the game. When you bake a cake, you can't ever get the eggs back. So when a game mechanic, bug or something is described as \"baked in\", it means it isn't getting patched out or radically changed because that would mean making the game over or changing it completely.",
"It’s hard to tell without knowing what you’ve watched, but in game development itself “baking” is colloquially any precomputation you can do to speed the game up, like precalculating lighting and shadows from static lights, model or material simplification, and such - anything that can be done “offline” to avoid having to work everything out in real time.",
"“Baked” as in, baked in an oven, a metaphor for saying the game should have had longer development time. Also there’s bake and / or “baking” as in the transference of high texture detail to lower polygonal models. Lastly “baked in” is most likely a reference to an aspect of the game design being woven into the core fabric of the game from its early inception.",
"Baking is pre-calculating something ahead of time, rather than doing it during the gameplay. Mostly refers to light. For instance suppose you have a dungeon with torches on the walls. The torches don't move, so the light patterns they make would stay mostly fixed. In such situations, the lights can be \"baked\" by calculating during the level design how they'd light the dungeon, and applying the effect of the light to the wall textures. If you were to remove a torch from the wall then, the lit part of the wall would remain in place anyway, because the game isn't actually calculating the light. This can improve performance by quite a lot."
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f7b4b3 | Why is it that in western movies and documentaries the pianos are sometimes playing by themselves? | Technology | explainlikeimfive | {
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"text": [
"There are special pianos which play themselves. The old style player pianos use long rolls of paper that have holes punched in them, and each hole is a note. The paper is fed over a metal cylinder with holes in it - one hole for each key on the piano. A mechanical pump (or, sometimes, footpedals) blows air through the cylinder as the paper is continuously passed over it and every time a hole in the paper lines up with a hole in the metal cylinder, the air pushes a level for a piano key*. Player pianos were used when a human player was not available (or affordable). & nbsp; *It's actually a fairly complex system of vacuum, diaphragms, and pneumatic actuators",
"Self-playing pianos that used pressurized air or electric actuators to operate the machine like a big music box were a popular novelty until the market crash in 1929. The song would be \"programmed\" onto a roller or perforated sheet and the piano would play it by itself, provided you connected power or pressurized air."
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f7c664 | How does Moore Law work? How does the doubling of transistors decrease pricing? | Technology | explainlikeimfive | {
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"text": [
"Moore's Law is an observation, not a causal relationship. If you notice a trend in cars that faster cars have brighter paint colors, that does not mean that brighter colors make a car go faster. Many industries are constantly improving, not by doing one thing but by finding new things that improve performance. Gordon simply noted the rate of improvement in integrated chips was pretty linear.",
"Moore's Law isn't a law, but an observation of how the price and transistor count of integrated circuit evolved and a prediction of how they would continue to evolve in the future. Moore's Law states that the number of transistors in ICs double every two years. (With the price staying roughly the same) This means that the price per individual transistors effectively gets divided by 2 every two years. This is possible because ICs are not made transistor per transistor. They are printed as a whole, directly on silicon. The silicon and printing process is what cost money, not the transistor."
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f7dmxe | How do airport security scanners know what’s a vitamin versus an illegal drug? | I have always wondered when I pack vitamins when traveling, how does airport security know what is actually a vitamin and what is, say ecstasy? | Technology | explainlikeimfive | {
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"It doesn't, all they know is you are carrying pills. Tons of people carry pills, so it rarely causes suspicion. Also, no one buys a plane ticket to smuggle 30 pills, so unless they see a suitcase full of them, they are not going to bother. Airport security is mostly about preventing people from interfering with air travel, not enforcing other laws. Actually, it is more about performing a little skit to give people the illusion they are being protected.",
"They don't at all! TSA is not looking for drugs, they are more focused on water bottles, liquids and other things that could be made into explosives. Flying with basically a small personal amount of drugs more than likely will go unnoticed if you are being calm and not making a scene! Know from experience, have flown with lsd, weed, shrooms, E/Molly and have never been stopped or subjected to a random bag search!",
"They don’t know. Especially if it’s just a small amount you’ll pass through just fine. People overestimate the efficiency of airport security/TSA all the time.",
"They don't know. Only way to know for sure is to test. As someone else pointed out, if you are just carrying one bottle and have done a lousy job of hiding it, odds are that it's nothing illegal. If it's a lot of pills they may want to test, or if there's an attempt to conceal them.",
"Airport x-rays are looking for liquids in container larger than 100ml, and handguns. Sometimes there are dogs looking for drugs, but that's more common in checked baggage processing. Dogs are super-selective, and they can tell your drugs and vitamins apart.",
"TSA is not a law enforcement agency. They shouldn't be concerned with what you're carrying as long as it's not risk factor for a flight. In practice, they may alert some other agency (DEA, FBI, Customs, etc) if they think they see something suspicious."
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f7g7mb | What changed that allowed TV shows to get such a huge jump in budget and production value? | Technology | explainlikeimfive | {
"a_id": [
"fib55ai"
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"text": [
"Here's a little info on GoT. With a total show budget of $1.5 Billion, the show has earned $3.1 Billion through HBO subscriptions alone. All eight seasons, spanning 73 episodes and bringing together 566 characters, cost HBO a mere $30.90 per viewer. Sauce: URL_0"
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f7hd5m | How does an RGB LED work? | Technology | explainlikeimfive | {
"a_id": [
"fibau1n"
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"text": [
"Are you asking how do LEDs work physically to make light or how they create different colors using only RGB color values?"
],
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f7mqr6 | What is the difference between 64 bit programs and 32 bit programs and does it have an actual effect on my computer depending on which one I choose? | Technology | explainlikeimfive | {
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"One really big difference between them is that 32 bit programs can only see up to 4gb of system memory, which is a small amount depending on the type of program. 64 bit programs can use up to 16 exabytes, or 17 billion gigabytes.",
"When we say \"32-bit\" and \"64-bit\", it's actually shorthand for two different kinds of CPUs with many differences. In the case of typical desktops/laptops these are more correctly called \"x86\" and \"x86-64\". Intel invented x86 decades ago, and AMD reworked it into x86-64 in the 2000s. x86-64 comes with many improvements over x86: * It can work natively with 64-bit numbers, which means it can process larger chunks of data at a time and less awkwardly deal with large numbers (you can write a program that works with numbers larger than the number of bits your CPU has natively, but it's awkward). * It can also use 64-bit addresses, which means it can access up to 256 terabytes of RAM (with the possibility to expand to exabytes in the future). A single 32-bit app is limited to 4 gigabytes of RAM for itself, and a 32-bit OS without special features is limited to about 3 gigabytes of RAM in total. * It has twice the number of CPU registers, which are the places the CPU keeps things it's working on. So the CPU can be \"remembering\" twice as many things it's working on, and they are twice as big too. * Some new features recently added to CPUs to be more efficient only work on x86-64. * Also there's a practical issue: while new CPUs add features to make things faster, apps have to actually use them. Since x86 is so old, apps have to assume you might be using a CPU from the 90s. Some apps can detect what kind of CPU you have and use more features, but most don't. Since x86-64 is newer, any 64-bit app can assume you have at least the features of a 2000s CPU. This makes every 64-bit app automatically use those features by default, making all apps faster. The downsides are that since 64-bit numbers are larger, they require more memory and more memory bandwidth. The same app will use more RAM in a 64-bit version (the difference can be anywhere from imperceptible to almost double, depending on exactly what the app is doing). One important thing is that (to this day) every x86-64 CPU is capable of running x86 operating systems and programs, by going into a compatibility mode. However, running 32-bit programs at the same time as 64-bit programs is more complicated. Because they are different types of CPUs (different architectures, even if the same physical CPU can support them), the different sides can't work together directly. To do that, your OS actually comes with two almost full copies of itself, one 32-bit for 32-bit apps, and one 64-bit for 64-bit apps. Then the core is 64-bit but includes a bunch of code to convert from the 32-bit \"language\" so 32-bit apps can run too. This only works to a point, which is why, for example, you can't use 32-bit plug-ins in a 64-bit app and vice versa. There are also 32-bit and 64-bit versions of the ARM architecture (used in most phones), and the story there is similar.",
"A 64-bit program can use 64-bit instructions, which entails nice things such as: * Large swathes of the modern instruction sets * More and wider registers * A dramatically larger address space Which in turn implies generally better performance and access to more than 4 GB of memory, should your program require it. A 32-bit program essentially cannot access most modern processor features. As a side note, while addresses are ostensibly 64-bit, modern CPU's only implement 48 bit address spaces, so the currently relevant memory limit is \"only\" 256 TB. There are servers currently available with on the order of 24 TB, for example, so that maximum is some ways away for now.",
"Think of how many house addresses your toddler can create with only 2 letters - you have been lazy and have only taught him A and B. Let's say each house has either 1 or 2 letters in the address. Your toddler spends whole day and manages to come up with A, B, AB, BA, AA, BB. 6. So while you are dreaming of making multi-millions selling those 6 houses, the Asian next door has slogged their toddler to go up to C. So now her toddler starts rattling off A B C AB AC BA BC CA CB AA BB CC. 12 And now since their are way more houses, maybe the house numbers will now allow either 1 letter, or 2, or 3. In which case the difference is even bigger. That was 2 bit vs 3 bit."
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f7mrwk | What's the difference between an emulator and a virtual machine? | Technology | explainlikeimfive | {
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"I may be off here someone with more low level code knowledge might be able to add-on to this but my understanding is: Virtual Machines only work on machines with the same cpu type because they just forward the actual cpu instructions to the host. This allows them to be fairly seamless when using them cause they can run at a normal speed. Emulators have to translate the cpu instructions of the device they're emulating since instruction sets vary on different types of cpu (for example a phone (arm) cpu and a desktop (x86) cpu) this means a translation layer has to exist and things that might be a single instruction on original hardware may have to be broken up into multiple instructions on the host machine. This means that your machine has to run harder than the original to get the same result.",
"Virtual machine - It lets you pretend your one machine is two. The two machines will use the same type of processor. If you use an intel processor, both your host machine and virtual machine will be intel machines. Emulator - Lets you pretend your machine is two, where the second is a different processor. If you use an Intel processor, the host machine is Intel but the emulated machine is PowerPC or ARM. Common case of an emulator you will see these days - Many Android emulators will emulate ARM on your x86 based machine. Or a PS2 emulator on your Intel machine (PS2 uses a custom CPU that is very different from your desktop computer). Common case of a virtual machine - Bootcamp for Macs. Not really commonly used by everyday people otherwise. But pretty much the entire cloud (AWS, Azure) use virtual machines.",
"These terms are somewhat overloaded, but generally: Emulator: I write a program that implements a processor in software. I write code to read instructions from the emulated program and execute them myself. This will be slower than the real hardware would have been, but if the original hardware was already slow- perhaps we're emulating a very old machine- this might not actually matter. I can simulate the original machine to any degree of fidelity I need, or simulate machines that are wildly different than the one I'm running on, or machines that no longer exist, or machines that never existed. If better performance is called for, there are techniques to translate the instructions to ones the host processor will run directly. Virtual machine: The processor I'm running on has a special feature. Using this, it will run instructions from your program (typically an operating system) but, if it ever tries to do something that would normally involve the hardware, it exits and asks my program what to do, so I can fake it, and protect the real hardware. This will run exactly as fast as the real thing (because it is the real thing) just as long as the program isn't trying to interact with hardware too much, because that's still being faked, which takes work. There are techniques to mitigate the performance impact here, too."
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f7pp72 | How do police body cams work, including what the wearer can control, how they’re charged and stored, and where the footage is kept? | Technology | explainlikeimfive | {
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"Officer turns on/off. Charged at police station. Downloaded and stored at police station.",
"Body camera is always on and recording, and “pre-buffers” 30 seconds of recorded footage before the record button is actually pressed. That way, when something happens in an instant, the 30 seconds before that instant can be reviewed. Often, things in the field happen so fast that a LEO must react within seconds. This buffer accounts for that. When the camera is plugged into a charging dock, it uploads its footage to an internet-accessed website for review."
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f7rz4n | Why do batteries charge quicker than they discharge? | Technology | explainlikeimfive | {
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"They discharge much faster than they can charge. You just have a charger that charges it as fast as possible (the limit) and a device that doesn't get anywhere near the max discharge. Typically batteries can be charged in 1-2 hours and can be discharge in 5-60 minutes. Not many devices will use those charge cycles, mostly it's planes and cars, both real size and RC."
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f7sfel | How does "auto generated subtitles" translate audio into text? | Technology | explainlikeimfive | {
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"It works almost exactly the same as digital assistants such as Siri, Alexa and Google Assistant do when they listen to your voice commands. Which is called \"Automatic Speech Recognition\" or ASR for short. First you need to teach a computer program to be able to recognize speech and match that to words. This is done by giving a machine learning program lots of examples to start with. Like *\" hello program* *here are hundreds if not thousands of hours of already correctly subtitled videos. Try to recreate it. \"* The program then works really hard until it is able to recreate the subtitles at which point you start to give it new videos without any subtitles to compare with. The program can now detect speech automatically but it is not perfect. It still makes a lot of mistakes. But the beauty of it is that it can learn from mistakes. All it need is feedback just like we do and hopefully get in school. If it hears \"Hello\" and thinks it's \"jello\" all you need to do is correct it and it will remember and expand from it. So now when you go to YouTube and turn on auto generated subtitles the video is either feed into this program on demand or has already been processed and the result is speech to text which is synced. Example of output from the program would be: At 2 minutes 34 seconds the word \"**Malarkey**\" is uttered. & #x200B; note: it is obviously more complex as machine learning is involved which is a whole other subject and is more complicated then i made it seem but the gist of it holds true. *Edit: Spelling.*",
"Basically you take the software that turns speech into text - \"Okay Google, how is what I'm saying to you right now showing up on my phone's screen?\" - and point it at a youtube video's audio track. Take all the text it produces and make it into a subtitle feed. Obviously it's not perfect, but it's better than nothing."
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f7siuc | Why do video game companies struggle to keep a good server stability in another region, if the Game is exactly the same? | So there are video game companies (no names here) out there who struggle to keep servers stable. But in other Regions the Server runs fine. Why ist that so? The Game is exactly the same. Yes they could be possibly more players in that other region, but AAA Companies have statistics over them, so they should now it? Lets say you need "1 Server XY" for 100 players, they should get "1 Server XY" for the other region too or not? | Technology | explainlikeimfive | {
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"Game companies don't host their own servers, they're usually in a big server farm, along with the servers of many other companies, in a facility maintained by a third party vendor. So the stability is subject to the stability of the underlying infrastructure."
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f7t4we | what is HTTP/3? | Technology | explainlikeimfive | {
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"HTTP is a protocol that the web run upon. It defines, basically, how the hyper text data will be sent between the server and the client (browser). HTTP3 is the third version of the protocol, which changes the transport layer to use UDP and QUIC (another protocols), among with other details that I'm not aware of. But basically, it tries to improve the speed of the internet using a more lightweight transport layer.",
"HTTP/3 is the new iteration of HTTP. In the new version HTTP changes the underlying transport layer protocol, to decrease latency and overhead. Arguably the biggest performance improvements will come from the initial connection setup between your webbrowser and the website you visit. With the new protocol multiple steps that are required before sending the actual data are packed into one, additionaly this data can be used for future connections to that server, vastly improving the time it takes to get data from sites you already visited. The other notable improvement in handling packet loss, so there should be slight performance improvements on unstable internet connections as. The improvement comes from less data needed to be resend. Also switching networks will have less of a performance penalty, so during commute you can expect way faster connection reestablishing. Tl;dr Makes the internet go a little faster by reducing overhead and improving latency.",
"Http/3 is based around protocols that reduces the steps required to create a TCP handshake and adds encryption between the end user and the application. The encryption enhances security for normal home internet users but it's going to be a challenge for corporations, schools and so on. This is because it makes Man in the Middle *theoretically* impossible. This makes inspecting traffic for malware and data leak of confidential info a bit of a challenge."
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f7w79x | How does the code work in a phishing email, so that the phisher gains access to data on the victim's computer? | Technology | explainlikeimfive | {
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"Phishing usually doesn't involve code. It's very similar to asking someone for their password and the person giving it up voluntarily. The idea is that you make the email seem legitimate and the user will think that they are logging into some legitimate site and they'll type in their password or give the information that the phisher is asking for.",
"There's two parts to this, malware and social engineering. Social engineering is convincing a person to give you data. So if you claim to be the CEO for example you might convince someone to give you account numbers or credit card info. Malware is a computer virus, malicious code that gets onto your system to perform a malicious act. This is referred to as a 'payload' and can be delivered by making a person click on a link to download an application, putting a macro in an excel document, or attaching the executable to an email hidden as a legit file that the user has to click on. But these tactics aren't used as much anymore because modern anti-virus programs and anti-spam tools are pretty good at catching that. The infamous Microsoft Support scam would call you and claim to be MS support over the phone. That's the social engineering bit. Then they would convince you to install remote control software on your computer so they can look around your PC basically giving them free reign to install any malware they want... as well as billing your credit card for the favor. More often than not nowadays they'll send you a link to sharepoint online, Onedrive, DropBox etc which contains the malicious file. One common scam is if you try to open their sharepoint link it prompts you for a username and password before seeing the file, the user then types in their username and password without a second thought and BAM the hacker now has your credentials.",
"A phishing website is coded similarly to a normal website. When you attempt to login, the credentials are saved to a database so the attacker can view them later."
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f7x2v2 | Where do all of the needles and other disposable sharps go after they get put into the sharps containers in hospitals? | Technology | explainlikeimfive | {
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"text": [
"Typically such potentially hazardous bio waste would be taken to a processing facility where it would be put through an autoclave, a device that cooks it with high pressure steam to destroy any biological hazards. At that point it can be sent to a landfill as normal."
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f85ahb | Why do live TV hosts experience delays when talking to reporters on the scene? | Like, it's the current year, if I fire up Discord, Skype or even FaceTime I can talk to or video message people on the other side of the country with close to zero lag, as if they're right here with me. Still, when I watch TV sometimes I see that there's a delay in the communication between the host and the reporter on the scene, even if they're in the same city. \- So, we have Jim on the scene to bring us the newest news \- \[camera focuses on Jim, 3 weird seconds passes\] \- Oh yeah, John, we're here with Ms. Davis who lost all her belongings on the Godzilla attack... | Technology | explainlikeimfive | {
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"All the apps you mention have the benefit of being able to use existing ground infrastructure; wifi is within a few hundred feet at the most and cellular a few miles before it is onto ground lines. Those are great if you can get them, but the field reporters want to be able to ensure they can speak without interruption which means they need to control every step of the network. To do this they typically use satellite communications, only needing to have a clear view of the sky from their van to form a video link no matter where they are. The penalty is that the much longer round trip distance causes a slight delay in the communications.",
"They’re communicating via satellite because it’s reliable from anywhere. If you’re ever near a TV reporting van you’ll see the dishes on the roof. There’s some delay from the signal bouncing off a satellite and back to a ground station near the studio."
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f86i87 | How does Google updating its TOS affect us? | Technology | explainlikeimfive | {
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"For the vast majority of users, it doesn’t. (IANAL) TOS typically provide two things; what the company will do with your data, and what you can and can’t do with the service. The former only affects you if you’re either going to sue google or stop using them. The former is probably well outside your financial means, and the latter only matters in so far as you’ve not already decided that the loss of privacy is worth the convenience of using google. The limitations won’t matter for most users. Google already reserves the right to terminate your service for pretty much any reason whatsoever, ask any Youtuber about it. Any new restrictions added to the TOS won’t realistically change the capriciousness that google can and does treat its users with, but it might give you a small warning about the kind of behavior they consider beyond the pale. For most users this won’t be an issue.",
"I've been asking myself this for a week now. No idea what is changing, but unfortunately there's almost no way I'd stop using their products and services so I haven't put much effort into finding out.",
"I got an email of an overview so check your email to see if you got one. Nothing major has changed. Essentially they've tried to make it more readable and expanded the services that it applies to."
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f87vsz | how does the gold leaf electroscope work? | Technology | explainlikeimfive | {
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"text": [
"The gold leaf electroscope shows induction. Induction is basically electrons attracting/repelling without transfer. When a charged rod is held near the top of the device it will attract or repel electrons within the metal rod. (For example a negatively charged rod will repel electrons from near where the rod is held and force them towards the gold leaf.) Because the gold leafs are so light, and at this point each contains a like charge, they will repel from each other. In addition to their light weight, the gold leafs are protected from any air current that might interfere with the repulsion between the two leafs. Hopefully this answers your question :) if not maybe these will help. if you wanted to know why the gold leafs repel when each is filled with a like charge, I don't know enough to explain that. Though due to the link between electricity and magnetism I assume its because of magnetic properties. In a more simple view you can view each electron or each leaf as having an electric field, these fields are easier to understand visually but are still somewhat similar to the magnet analogy. If you wanted to know how the charges move, that arises from metallic bonding. In short when metal atoms bind they'll form a lattice in which some electrons will be free to move about the lattice. This property in metals is why they are good conductors and is also responsible for why they appear shiny."
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f89ec5 | difference between udp vs tcp ???? | Technology | explainlikeimfive | {
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"text": [
"TCP checks everything. It's slower, but more reliable: * A: I'm sending you a thing! * B: Acknowledged! * A: Here's the thing! * B: I got it! * A: I'm done sending things now! * B: Acknowledged! UDP checks nothing. It's faster, but less reliable: * A: Here's the thing! * (That's it) UDP is better when speed is crucial (e.g. gaming). TCP is better otherwise, whenever a slight delay doesn't matter (e.g. most anything you do online).",
"UDP is like getting a letter in the mail containing all the requested information. TCP is like getting a letter in the mail, calling the sender, and verifying the words on the letter."
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f8c1ht | How are real life pictures stored and/or transferred to electric devices? | Technology | explainlikeimfive | {
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"yes, a picture can be converted into a set of 1s and 0s. A digital picture is just a grid of pixels, where each pixel is a collection of 3 colours, red green, and blue. typically each colour is represented by an 8 or 16 bit number, so either 24-48 bits per pixel. These can be sent as 1s and 0s over radio, wire, etc.. and understood at the other end."
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f8cm8u | How are games made 'moddable' without revealing source code? | Do they just have a very abstract and capable API? some mods for some games can be pretty complex. | Technology | explainlikeimfive | {
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"More or less. It depends on the game. Some just offer great hooks that allow people to write scripts to accomplish their goals. Other games have a very fixed file structure and will essentially grab mod folders and treat them as an extension of their data store, running everything contained therein: Does your mod have a folder named \"government_types\"?, well ,everything contained therein will be treated as a government type definition for this game. You don't need to reveal the source code to make something moddable, all you need is allow modders an entry point to extend the functionality and robust documentation so that people know what to do.",
"Most games do not store their game data the same way they store their code. So it is possible to reveal the format of the game data and not the code. This makes it possible to change or add textures, 3D models or even complete levels. Some games might even have systems for the NPCs and scripted events in an easy format that can be changed. This may have started off as a way for the level designers to work independently from the coders but have the effect that third parties might also change the game content. A lot of games is also written in a way that makes it relatively easy to reverse engineer the source code. Languages such as Java and C# have the disadvantage that the resulting compiled code is relatively easy to decompile. You may not have the variable names and the exact structure which makes it a bit hard to work with but it will allow you to make changes and test them out.",
"So one thing to remember is that there is source code and then there are game resources (graphics, sounds, parameters stored in text files, etc). Usually modding is done by modifying resources. To take an example - let's say that you have a car racing sim. The game will have a folder structure where you can throw in car \"skins\" or models, it may provide the ability to enter the car's parameters in a text file (how much power it has, how much tire grip, etc). Game's source code will \"know\" where to look for those resources and how to use them, provided they have the right structure and format. I don't think APIs are used that much for typical modding. They may be used more for capturing game data. In the racing game example, it may allow you, for example, to capture more telemetry than the basic game."
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f8duzb | How does side-chaining in music work? | Technology | explainlikeimfive | {
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"The volume, or low pass filter, or really any filter, is automated to activate whenever the volume of a certain sound comes on ( a kick drum). For example, if you have a kick drum playing, the sound of the other track would suddenly get quieter for a short time whenever a kick is playing."
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f8f2s7 | I’ve read that computers can crack short passwords instantly so we should have complex passwords, then why are ATM PIN numbers so short? | Technology | explainlikeimfive | {
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"One reason is that ATMs require dual verification: You need to have your card and your pin to make the transaction. Longer pins will be more secure but harder to remember. But often when people lose their debit card they report the card missing immediately so the thieves and hackers dont have much time to use it anyway.",
"Computers can only quickly crack short passwords when they can also only quickly test them. For example, if a website has no throttle on incorrect password login attempts. At an ATM, someone still has to physically press the buttons, so the speed is limited by that."
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f8fdin | Why are HDDs still used more commonly for servers instead of SSDs? | Technology | explainlikeimfive | {
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"text": [
"SSDs getting cheaper, but still much more expensive than HDDs for the storage capacity. For your own computer, it may not be a big deal to spend $100 instead of $50 for storage, but when you're spending a million dollars on storage for a server farm, it matters a lot. The advantages of SSDs also don't matter as much for servers."
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f8heih | how do computer circuit board work? | Technology | explainlikeimfive | {
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"The board is pretty straight forward. The metal on the board carries electricity. What matters is the little buildings, as you put it. Some, called resistors, limit the amount of electricity on the board. Others, diodes, only let it flow a specific direction. Some store electricity, but most importantly, the transistors - they can change how the electricity flows based on an input. It's helpful to think of electricity like water here. (It's completely untrue but it works) The flow of the water is determined by the buildings which work like little gates and depending on how the gates switch, the water (power) moves where it is needed.",
"the circuit board is literally just several layers of fiberglass and embedded copper wire. there's nothing else about it. the magic all happens in the multitude of components that are connected onto the board, each with it's own behavior when stimulated with electricity. these components are culmination of decades of advancements in semiconductor science and manufacturing. some components are just a resistor or layers of thin metal to form a capacitor. others are a complex microscopic maze of nano wires and layers of wires to form an integrated circuit.",
"The main thing that makes it work is transistors. A transistor works similar to how the light switches in your wall work. When you flip the switch it connects 2 wires and lets electricity flow. A transistor replaces the physical switch with a 3rd wire, so by putting voltage on that wire it does the same thing as turning on a physical switch. All those little black 'houses' on a circuit board are full of transistors hooked up together in particular ways, and the pins attaching them to the board are the wires. You apply voltages on some of the pins and voltage comes out of the other pins depending on what \"input\" pins they felt and how the transistors inside are arranged. When you build a circuit board, you don't need to know exactly what's happening inside, but you do need to know what the chips is supposed to do, so you get a spec sheet that tells you. For a simple example let's look at the common 555 timer. [The chip looks like this]( URL_4 ). If you could break it open and examine the guts under a microscope you'd see a bunch of transistors and wires. [Here's a diagram where all the red things with 3 wires are transistors.]( URL_4 ) The red squiggly lines are resistors that just help limit current. At this point you could do a complicated circuit analysis based on that diagram to figure out what the chip does, but instead the manufacture makes a datasheet that tells you what the pins do and how to hook it up to get it to do stuff. They'll put in a diagram like [this]( URL_1 ) and tell you that if you do that that the output pin will send out a square wave that alternates between +5V and 0V like a clock. So you could hook that to a circuit board, then the circuit board has copper traces that run from the output of that chip to some other chip that uses that signal the 555 timer is producing. What a computer is doing is chaining together a bunch of these circuits together like a Rube Goldberg machine so that at the end you have wires that tell you that 'the answer is 16' or that send a video signal of a frame of Minecraft or whatever it is you want to do. If you're interested in spending hours and hours watching a guy build an 8 bit computer from scratch you can check out [this playlist by Ben Eater on Youtube]( URL_3 ). I think all you need to know that he doesn't teach in the videos is how the holes in the breadboard are connected to each other, which is a pretty easy Google search. There's also a lovely 18 minute video by Matt Parker that demonstrates the concept of computing things with a mechanical or electrical device using dominos which you can find [here]( URL_2 ). He also used the concept from that video and used some volunteers to make a domino calculator that can add two 4 bit numbers together, which you can find [here]( URL_0 ). All the places where it's not just a straight chain of dominos would be a transistor in the computer. The straight chains would be wires."
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f8jf93 | Why is it that when a video is sent from Android to iPhone and vice versa, the quality is extremely reduced? | It's always seemed weird to me that photos seem to be the same quality as the original (or very close) when sending to and from the same devices. Thank you in advance! | Technology | explainlikeimfive | {
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"When you send a picture or video cross-platform it has to send through MMS which typically has a limit of 1MB. Generally a photo is going to be around 3MB so it'll have to compress to a third of is size to reach that limit, a ten second 1080p video can fall around 30MB so it'll have to compress to being a thirtieth of it's size to hit that same limit. (These file sizes I'm using aren't going to be exactly the same for every phone but are what I got from my phone and settings.)",
"Is there any way to combat this? I've had this problem ever since I got the galaxy 10",
"It's probably more about protocol than device. For instance, when texting between iOS and Android, you have to go through SMS or MMS, and those systems probably compress images significantly.",
"What are you using to send those videos?",
"The way around this (if sending from an Android phone) is to open Google Photos, find the file you want to share, click the share icon, and choose \"copy link\". Send that link via a text message. When the recipient receives the message they will get a link to a full resolution picture or video.",
"That's so crazy I was just wondering this yesterday and then this popped up as a notification today"
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f8jfij | Why do computer games require installation while console and handheld games typically did not until the 8th generation didn't? | Been wondering about this for years. | Technology | explainlikeimfive | {
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"Those game cartridges were essentially portable disk drives, with the game already pre-installed on it. Unfortunately, it did have space limitations which could be an issue at time. PC games had no reason to do this once hard drives became mainstream. Installing to the hard drive allowed for much larger, more elaborate games than were possibly on console. But earlier PC programs actually DID work this way. Programs(including games) were on a cassette tape and loaded each time you played them and later games were played directly off of a floppy disk with no installation involved because there weren't hard drive to install them to. Hard drives changed everything. Console games eventually did the same thing, but it just took longer.",
"Answer: Reading from a hard disk is quicker. Consoles typically were supposed to \"ready to go\" and require few to no upgrades, like a hard drive, which made it easier to market to technologically inept consumers. Computers were made to be modular, so it makes sense for games to be installed on hard drives for efficiency. As the internet and social media have made it \"cool\" to be more technologically knowledgeable, consoles have been able to adapt modular hard drives, which allow for more efficiencies.",
"It's always been a matter of speed and pricing. Early disc drives were slow and real time games need a bunch of data fast. So as soon as hard drives were a thing it made sense to install games to them so that games could load faster and do things like stream data in mid gameplay. Consoles lagged behind as they always do because they had to much cheaper than a full blown computer. Consoles were still able to rely on disc drives for awhile as the read speeds had become faster somewhat or consoles like the n64 used cartridges which while expensive where much faster than discs. Hard drives were always the better option but still too expensive for consoles so they just kept increasing disc drive speeds. The 360 / ps3 generation finally saw hard drives hit consoles but the sizes were too small to make installs mandatory. Some games forced it on the ps4 (the blu ray drive was slow) but none did on the 360. They hit a wall with the 8th generation though because games started requiring absolutely massive amounts of data on the fly and the disc drives speeds couldn't really keep up. Installing to the hard drive became necessary to ensure games ran properly plus hard drives had finally become cheap enough to include in consoles at a reasonable price."
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f8q9jr | How are photos of deep-sea fish taken? (Assuming you would need to add light/flash due to the absence of light down there.. which might harm the animals?) | Technology | explainlikeimfive | {
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"You use powerful bright lights and yes this can harm the creatures at those depths. Short exposure to bright light itself is unlikely to damage normal tissues, but can very easily blind creatures which are hypersensitive to light. First off, many deep sea creatures are blind anyway. Of the remainder, many have no use for their sight and function normally without it. The remainder may go blind and die. For scientific purposes red light is often used since it does the least, or even no damage to these creatures."
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f8r2jg | Why do companies continue to make oversized power adaptors that block other outlets ports instead of making them more space-friendly? | Technology | explainlikeimfive | {
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"The efficiency limits how small the adaptor can be. Below 15W, it is not difficult to package the adaptor into a small form factor (as many have done) without a lot of cost penalty. However the newer power hungry adaptors that output 20W or more become problematic. Also the up-down format for many US dual sockets is a bit hard to design around. Typically, the mfr tries to limit the width of the adaptors somewhat to accommodate the side to side placement of multi sockets. Also note that many countries use different plugs so making an adaptor too narrow makes it difficult to accommodate the different plug styles.",
"except that laptop chargers generally have the \"brick\" further away. they have a cable between the power outlet and the \"brick\" so as not to take up all the room on the power strip. One would hope that other vendors would do the same thing, for that very reason.",
"From reading some comments I understand they need to be big if they draw a lot of electricity but why can’t they make it a brick in the middle of the wire (like Xbox) instead of a giant plug that blocks out the outlet?",
"The simple answer is they need to be that big. If you just shot the 240V of the outlet up a USB power cable it would fry and (likely irreparably) damage everything downstream of the outlet. The power needs to be, well, adapted, so the device and cable can handle it, and the hardware necessary to do that takes up some space",
"It's most likely the cheapest option that works. You could make the adapter long and skinny, but then it sticks out of the wall so far that it might get in the way of other things in your house, and if it's too long, then the block will act as a level and put unnecessary stress on the prongs and outlet.",
"the answer no one is willing to provide: big surge protector and big extension cord are pulling the string",
"The bigger question is why don't they just put the outlets 90 vertical instead and this wouldn't be an issue"
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f8sz99 | How are internet cables implemented in the ocean and then connect with an existing network? | Technology | explainlikeimfive | {
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"The cables are laid by ships which carry the cables in huge reels that play it out as they move. The route the cabling will take is planned in advance after surveying the ocean floor and the ship keeps a precise plot through GPS. The cables themselves are huge bundles with many components including fiber optics, steel and kevlar cables for strength, and copper wires for power. Fiber optics can transmit signals over huge distances compared to copper, but not all the way across an ocean and so at regular distances a repeater is installed in the cable. The repeaters take incoming optical signals, amplify and repeat them. Naturally this requires electrical power, which is why there are copper wiring in the cable as well. The ships can't carry thousands of miles of cable all at once and so lengths of cable are spliced together on the ships and they are re-supplied regularly. For most of the route the cables are also deep enough that storms and passing ships won't pose any risk to the cable. However as the cables go shallow closer to shore, and especially as they exit the ocean, it is necessary to bury the cable in the sea bed in order to protect it. The cables usually leave the ocean under ground where they terminate at special buildings with concrete piers to secure the cable as well as housing the network equipment that transmits on the cables."
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f8tten | - How is gravity induced in spaceships traveling in space? | Technology | explainlikeimfive | {
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"What makes you think it is? In general the only practical way this can be done is by having a rotating structure and using centripetal force to simulate gravity. To date - mankind has not built such a structure in space.",
"At the moment, we dont \"Generate\" a false gravity field in space, but if we did, we would use centripital forces, if I remember correctley if you can get a rotation rate of 3RPM where you're away from the cental rotation point by anything over 5 meteres (Distance probably wrong), it creates an artifical gravity because of the force. The easiest way to understand this effect on earth is, get yourself a bottle or bucket of water, make sure the top is open. Now spin your arm up and down (Head shoulder spin direction) at a fast enough rate, the water will not come out of the container because of the force. You can do this above people and you won't get a drop on them, unless you stop with the top facing down! This video does a good job of experianing the process :)[ URL_1 ]( URL_0 ) The only other way would be once we figure out how to control Gravions or the Higgs Field (But the higgs field is just a bad idea to mess with) \\*EDIT\\* After Someone spotted a few issues with my comment thought I'd make it more relevent. With a 76m Diameter and about 3 RPM you can generate about 1/3 of earths gravity. The reason they go for 76m is because it's allows for a slower rotation period to the astonaught, providing less discomfort. Think about if you spin something on a string around, if's it's farther away it's travelling further but at the same speed as at the center, which is travelling maybe an inch compared? If you look into this study it quanitifies their findings as to what is a comfortable rotation rate and size to generate 0.3-1G [ URL_2 ]( URL_2 )"
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f8wzvc | What does "virtualization with amd" mean? | I'm building my own PC / Hackintosh and someone told me virtualisation wasn't possible with the AMD processor I'm planning to use. But what does that mean? I tried to google it but haven't found a clear answer. So please explain this to me like I'm 5. | Technology | explainlikeimfive | {
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"Virtualization is a technique where you run software defined virtual machines (VMs) under the control of a small hypervisor operating system. AMD support isn't available from several hypervisors, because they instead use Intel virtualization extensions to the x86 instruction set. So \"no virtualization with AMD\" might be a true statement, under certain prevailing wind conditions, but why would you care. You're making a PC, presumably to run Windows, browsers and maybe some games. These are not VM technologies, so the fact your computer can't do something you don't want to do is ?? True but not interesting?"
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f8zlmy | What happens to the data from an install if I stop the install before it's complete? | I tried googling it, but I can't find any answers to this. Basically, if I am installing a game, for example, and it gets to 91% done, but then I have to stop the install because I need to go someplace and can't leave my computer on the whole time, what happens to that 91% downloaded/installed? Does it stay, so I could finish the install later? Does it completely reset? | Technology | explainlikeimfive | {
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"the downloaded files will usually be stored in a folder designated by the system as temporary storage*. Some installers will check for this already downloaded data and resume where you left off. Others (e.g. Origin client) simply start over from the beginning. The install itself (copying files from temp storage, creating registry entries, etc.) will almost always have to be restarted from scratch simply because it's easier (for the programmer) to just make the necessary changes than it is to check what changes have been made already. *temporary storage just means the operating system is allowed to delete those files if it needs the space (some will even clear this area of old files on a regular basis)",
"Depends on how the installer is coded. On Windows, an installer is just a computer program, and can work in pretty much any way it wants to. Based on personal experience, I would say in quite a few cases you'll end up with a partial install. Because undoing 91% of an install requires keeping track of exactly what has been done so far, and knowing how to undo it, and not nearly all installers do that.",
"There's no one answer. The basics of it, however, is that an installer is just another program. There are off the shelf varieties (\"InstallShield\") but most games have their own in-house installer. In the old days (Windows 95), installers used to leave shit all over the computer (because, surprise! Windows required it to work like that!) and often did not clean themselves up either during a partial install or an uninstall. This meant files left in c:\\\\windows\\\\system32 and settings left in the Windows Registry. Since then, Microsoft has changed the rules a bit, telling software developers you don't need to put crap in the system32 and can leave it in your own folder, often whatever folder the application used under C:\\\\Program Files. As for settings, well, the registry is still a mess, with programs still needing to add themselves to various parts for random functionality. An example of this is when you install a photo editor like URL_0 , it registers itself as a program to open, say, gif files. When you right click on a gif, you can open it directly in that program right from that right click menu, which it did by adding a specific setting in the registry. If you know where to look, long-removed programs still probably leave their shit all over the registry. A well-made installer will keep track of what it did and when it is canceled mid-way or the program uninstalled, the installer will remove everything. That sometimes still isn't the case. Bonus paragraph! You might have heard of the Windows Store. Programs on there are a special variety. Microsoft calls the technology used to make them \"Universal Windows Platform\". A UWP app is a self-contained program and are not *meant* to use the registry and can only access their own folder and a scant few other special-access folders on your computer. They are installed to C:\\\\Program Files\\\\WindowsApps and are intended to be mostly hidden from you. Uninstalling a UWP app should be just deleting its folder and maybe a few other things Windows should sort of automatically know about because the install points are all known locations, and not random shit all over the registry or your hard drive. This is because Windows itself is the installer, just like when you install an app on an iPhone or Android phone, and knows what it has to do.",
"5yrOldAnswer: When the install runs, it starts putting files where they are supposed to go. If you stop that, depending on how good the installer is at its job, it can: A: Clean up everything it did like it never happened and wait for you to run it again. B: Remember what the last thing done was before you stopped it and pick up from there if you try again.",
"Let's say you're setting up a pillow fort. No one knows where it's located. They can try searching for it room by room, but your house has 50 million rooms so that would take forever. You told your friend Steve that he could tell anyone where the fort was once it was done, but you wouldn't tell him until you were done. You start building the fort, but halfway, your mom calls you down for dinner and you never actually got to finish the fort. Since you never finished the fort, Steve never learned of its location. Half of it is still in some random room you picked, but no one will know where it's at unless they do the room by room search. Basically, data gets written to the hard drive and at the end of a completed write (\"install\"), there's an information \"table\" on the hard drive that gets updated with the location of that data so that when you double click PathOfExile.exe, the computer just goes to that \"table\" to get where the location is on the disk and then goes to that position on the disk. If an install stops half way through, that \"table\" doesn't get updated with the location of the data. The data still exist there, but it's not protected. It can still be overwritten whereas the completed install of Path of Exile protects the location of wherever PathOfExile.exe points to so that nothing else can overwrite it."
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f91nfi | How do phones know you got a text, snapchat, etc... without soaking up a lot of data? | It seems like if they were constantly checking if you had a notification from any app it would use up a lot of data quickly. | Technology | explainlikeimfive | {
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"Since this is really about power consumption, the answer is the phone turns off the radio. Basically it tells the cell phone it's going to turn off for a second, and if any data for the phone comes, it must be announced at exactly that second and the phone will power up it's radio and download the data. If no data comes it will immediately turn the radio back off. As for apps, internet connections over TCP support connecting and then waiting for transmissions so apps can use this to allow the phone to power off while connected. On Android many apps use this directly, but both Apple and Google offer push services that optimize this and put all the app notifications on one connection to reduce unnecessary wake ups. Apple actually forces this on their developers.",
"Imagine if whenever someone wanted to talk to you, they had to talk to jimmy first who is on the other side of the room. Every minute you ask jimmy if there is a message for you, and he says no. That is your phone checking if you have received a message. Every now and then he says yes. When he does, you then say “send it here please” and then he sends it to you. This is conversation was much longer and had more information transferred. This is your phone receiving the message. It costs much more data to receive the message compared to checking if there is one to receive. It doesn’t cost much in the big scheme of things tho because this data usage for both checking for a message and receiving a message is very very very small. SMS text messages use 7-bit characters and have a maximum length of 160 characters, making the maximum data size of each SMS 1120 bits, or 140 bytes.",
"It checks in with a central server. Called a \"push\" server. (For Apple it's called APNS) The server will tell the phone if it has any notifications. The convo is cheap since it's just a yes/no question, doesn't use much data at all. If it does, it will send data/notifications to the phone. If it doesn't, it just says no and nothing else happens In either case your phone will continue to ask the server as long as you have push notifications turned on.",
"You are at home waiting for the mail to arrive. You could go outside, walk to the mailbox, open it and check inside. This of course takes a lot of work (data) of you do it often. Instead, the mail man raises the little red flag on the box of he delivers something. Now you only have to look out the window to know if you have mail. Saving you a lot of work (data) each time. The heavy cost only come once the flag is raised and you want to fetch the mail."
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f99d2w | How RAM in mobile phones differs from RAM in PC's. Are they interchangeable?? | So much brouhaha over the 16gig ram variant of Samsung S20 Ultra with everyone immediately referring to laptops of similar or lower specification as if the RAM is interchangeable. I'm a noob so clearly there's plenty I don't know. I'd like people in the know to help explain this. Thanks Y'all | Technology | explainlikeimfive | {
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"The technology is the same, but that's about where it ends. Laptops and desktop computers usually use removable cards with the chips soldered on top of, whereas every mobile phone has the chips soldered directly on the motherboard.",
"The RAM chip is basically the same for phones, desktops/laptops and all electronics. The difference is the hardware they have to accomodate. Computer components produce alot of heat, so desktops and laptops require cooling systems. Phones do not have the space to encorporate active cooling systems so they rely on passive cooling to the environment and use special low power electronics."
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f9cxzh | How is it that you can take a picture of a piece of fruit and blow it up big enough to slap on a semi truck while making look delicious and not all pixelated? | Technology | explainlikeimfive | {
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"Graphic designer here. Others are referring to the difference between Raster and Vector images, which is definitely a factor, but any actual photo would be Raster, so vector curves don't apply. For photos we start with very high resolution images that haven't been heavily compressed or degraded by a website gallery like facebook or instagram. Ideally the images are sharp and do not have the characteristic boxy pixels that you get when you zoom a couple clicks into a photo on the internet. Often the photos start at about 2.5-3 feet wide at the pixel resolution they'd print on a semi trailer (just an example, it varies widely on layout … and semis use a pretty low resolution meaning the photos can print large without adding new pixels). From there we just up-size them in software like photoshop to get to the final needed image size. Photoshop looks at every pixel in the image and decides what the new pixels you are adding to the image should look like. I won't pretend to understand the algorithms they employ to make the magic happen, but the results are very good when you start with a quality photo. After the image is sized correctly we'll add sharpening, clean up any rough edges or blockiness, and put it into the overall layout. The biggest component is your distance from the semi when you see it. Many would look a little blurry or not too appealing if you were standing book-reading distance away. It's the same with billboards. They're viewed from hundreds of feet away, and are printed with a relative very low resolution, so you can use a pretty iffy image and have it look fine.",
"Note: I have a limited experience with digital manipulation of photos, but I know a little. There's blowing up pixelated images to giant size, but there's also vectorization. Instead of making pixels bigger and therefore more visible, the shapes and colors are converted into scalable images. No matter how big they get, they scale up with no pixels. It's the difference between Photoshop and Illustrator, and why things like fonts can get huge without pixeling out.",
"Imagine pixels, each one representing a dot of light, more pixels in a small space better the resolution. Now think of your eyes. In your eyes there are millions of cells that receive light, think the opposite of pixels (they receive light instead of sending it out). Cameras work like your eyes, they receive light. The more “receivers” in a small space in a camera to capture light mean better resolution. With a good camera that image can be taken and then conversely be used to produce an image that can be enlarged but still keep the dots small so things remain clear.",
"The graphic is probably in what is known as a Vector format. Vector, in a nutshell, means it's made with math, rather than colored pixels. *Stephenw78* definitely explained pixels pretty well, and the fruit certainly started off that way when photographed. From there, computer software can break it down into areas of solid or very similar color, giving those areas geometric edges calculated with a fair amount of precision, including measurements for corners, angles, and curves. This is done because math can scale. If an image is 10 inches across or a 1000 inches across, the curves of any solid lines would just get multiplied too. So if that vector graphic looks good on your screen, it should look good as a billboard as well. Because curves and lines that make up the image now don't actually have definable depth, and the colors of the image are areas, not pixels at this point, enlargement doesn't enlarge individual pixels into jagged edges that would be noticeable and ruin the graphic."
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f9d35y | What is an API? | Technology | explainlikeimfive | {
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"API Stands for Application Programming Interface, It is essentially in the simplest way, an API lets programs and software request information from the OS, Servers etc, allowing it access to Services and Functions that don't exist in the applications code"
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f9d5y1 | Why is it that phone these days aren’t completely water proof? I get that the boards are sensitive to it, but can’t they just use water proof paint on them? | Technology | explainlikeimfive | {
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"Unfortunately your phone board, battery and electronics all generate heat. That heat has to go somewhere and usually out through some part of the case is where. Adding paint to it will reduce the ability of the heat to dissipate. Furthermore, the case has to be in two parts so you can get the board and the screen and all of the guts into it. And where you plug headphones, USB cable, buttons... these are all holes in the case that have to be sealed. And proper water sealing is hard - to do it right requires the right material, careful manufacturing processes and all that adds up to $cost. If you over-tighten a screw just a little bit, this crimps the waterproofing gasket a little creating a hole that water can get through. So there are numerous ruggedized and completely waterproof phones. But they're $expensive, of if they're NOT $expensive they are lacking some features that perhaps other phones have in order to keep the cost down.",
"iPhone 11 Pro and iPhone 11 Pro Max have a rating of IP68 under IEC standard 60529 (maximum depth of 4 meters up to 30 minutes). This is \"waterproof\" for most practical purposes. The trickiest bit is letting sound out, through a reasonably high fidelity speaker, while being waterproof. Circuit cards aren't the sticking point, as they can have a conformal coating (the engineering term for waterproof paint)."
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f9ihy0 | signing algorithm vs encryption algorithm | my eli5 illustration on encryption is that I put a muffin in a box and lock it with a key (key number 111783) and I send that box to my brother. my brother need to have the same key (number 111783) in order to open the box and get the muffin. without the key my brother will not be able to enjoy the muffin. and in tech term the key is a certificate is that correct? & #x200B; now what is signing algorithm in that illustration? is there relation at all? thank you | Technology | explainlikeimfive | {
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"> my eli5 illustration on encryption is that I put a muffin in a box and lock it with a key (key number 111783) and I send that box to my brother. my brother need to have the same key (number 111783) in order to open the box and get the muffin. What you're describing here is *symmetric key encryption*. It's called symmetric, because the same key is used on both ends. In order to sign something, you need *asymmetric key encryption*. Asymmetric encryption is not all that different. Instead of a lock coming with one key, each lock comes with two keys, a red key and a blue key. If you lock the lock with the red key, only the blue key can open it, and vice versa. This lets you do lots of useful things. If you keep your red key secret, and then distribute copies of the blue key to the general public, then anyone in the world can send you a cupcake, and they will be sure that you and only you will get that cupcake. They put a cupcake in a box, lock it with a blue key, and now only your red key will open the box. Now, let's say you want to send a cupcake to the world. You want anyone to be able to get the cupcake, but you also want anyone to know that the cupcake is *from you*. You put the cupcake someplace publicly accessible. You also take a selfie with the cupcake. You put your selfie in a box, and lock that box with your red key. If someone takes that cupcake, they can open the box with their blue key and retrieve the selfie to verify that the cupcake is from you. Because the blue key opened the box, that proves that the box was locked with the red key. You're the only person with the red key, so it proves you locked the box with your cupcake-selfie inside it. That is a cryptographic signature.",
"A signing algorithm proves originality. So instead of a lock that can’t be opened without a key, it’s a photo of the original muffin in complete detail, but the muffin isn’t locked up. Anyone delivering the muffin can eat it and replace it with another muffin, but they can’t change the photo (they can remove it). Your brother gets the muffin and if there is no verification photo, is suspicious that it’s not the original muffin. Or uses the photo to inspect the muffin to determine if it’s original or not. To:dr: encryption stops others from reading the content. Signing stops others from changing the content."
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f9lh37 | Why can’t they make lunch meat without nitrates? | Technology | explainlikeimfive | {
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"text": [
"They can, but they're used to help fight off bacteria. This means a longer shelf life, so companies like using them."
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5
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f9mph9 | can someone tell me how Airtime Fairness works | Technology | explainlikeimfive | {
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"text": [
"Say you have 3 devices A,B,C on a wireless network all of them want to send 1 mb of stuff. If all 3 devices started trying to transmit at once, their signals would mix up, so you figure, OK we’ll tell them to transmit one at a time. So you go,”A, send me everything, then once you’re done, B goes, then C.” Then you realize that A is a really old device and it’s going to take a hecking long time to send everything. Which means B and C (two modern ultra fast devices) are going to be stuck waiting for A to finish. This sucks. So we invented Airtime Fairness. Now instead of saying A finish, then B finish, then C finish. We say “A, you have x number of miliseconds to send as much as you can, then B has x miliseconds, then C” A, can’t send a lot, but sends what it can, B’s up next and finishes, C’s done in one go too, so now we’re back to A, while B and C go on with whatever they were doing."
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f9risv | DNS Reflection attack | The part I got so far was "swamping an ip address with requests that are far too big" but I feel like I'm missing out on the detailed info. How does a DNS Reflection attack actually take place, and why does it work like it does? | Technology | explainlikeimfive | {
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"There are 3 parties in this attack: the attacker and the victim, plus a (relatively) innocent DNS server. Attacker sends a request to the DNS server requesting information, but forges the source IP address of the request to the that of the victim as though the victim requested the information. This request packet might be around 50-60 bytes large. Important to note this same request is sent over and over again non-stop at the attacker's maximum transmit speeds. The DNS server responds with the answer to the query, but the information contained within is much larger. One simple example is the query for type \"ANY\" on URL_0 which returns about 446 bytes of a response packet, but it goes to the victim rather than the attacker since the original request source was forged. So for each 60 bytes consumed by the attacker's internet connection, 446 bytes actually hit the victim which is a 7.4x multiplication factor. So if an attacker has 100 megabit of internet available, they can use a DNS reflection attack to hit someone with 740 megabits of data. And I'm sure with some effort you could find a query that makes a much larger response. That 740 megabits comes from the DNS server's internet connection, but big companies who have DNS servers usually have fast internet. And that's what's happening: the attacker is taking advantage of someone else's internet to both hit someone with a lot of data and remain hidden themselves. In a real attack there would be multiple DNS servers (ab)used in case one maxes out or gets pulled down."
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f9rv3p | What does ultrasound gel do? Why is it necessary? | Technology | explainlikeimfive | {
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"Sound waves get bent and/or reflected when they hit a boundary between materials of different densities. The ultrasound wand and the human body are of a similar density, both much higher than air, so the ultrasound struggles to get through the air gap between the wand and your body. The gel fills the air gap and is the same density as the body, so the ultrasound can pass through without getting bounced around.",
"Try putting a straw in a glass of water. It looks funny, doesn't it? Like the straw is broken at the surface of the water. That's because light travels differently through water than through air. When it goes from one to the other, it gets bent. Sound works sort of the same way, and if the sound had to go through the air, then through the tummy, the picture would get all messed up, like if you took a picture of the straw in the glass. The gel is similar to your body, so by using the gel the sound doesn't go probe- > air- > body, it just goes probe- > body, and you get a pretty picture! Try filling the glass all the way with water, so the straw is completely underwater. It doesn't look broken anymore. It's kinda the same thing.",
"For what it’s worth ultra sound has industrial use. Gel used for coupling to steel is just Vaseline.",
"It stops any extra air space between your skin and the probe so you have a clearer image of the fetus",
"You know when you are in a swimming pool with your friend and he makes noise underwater you hear him super loud if you are underwater too? It's because water transmit sound really well. So well that whales use it to sing to each other and it will work even at hundreds of kilometers apart. You know also it's hard to see him when he is underwater but you watch from above, because the surface is hard to see through, it moves and reflect the sun. But if you go underwater with a mask it's super easy. Ultrasound is sound that is so high pitch it is really precise (you can see with echolocation) but also really fragile (a piece of paper stop it). Ultrasound had the problem that if there is air between the device and the skin then the sound will enter the air, get cushioned a little bit (so you lose some of the power), then bump into the skin and reflect (like at the surface of The water). So you get a really good image of the skin... But not great of what is below. If you add gel you avoid the cushioning (gel transmit sound as good as water) and the device is \"under water\" and does not see the reflection. The gel has to be the same indice of refraction (for ultrasound) as human flesh. Then it's as if the device was \"inside\".",
"I know its not exactly ELI5, but this video by Steve Mould has an excellent explanation with demonstrations that most laypersons could understand. URL_0",
"Bc sound waves move better thru a medium than it does air. Kinda like whales/dolphins using sonar for miles under water but in air sound gets dispersed and doesnt travel as far",
"I tell patients it’s so that the sound waves that we use to make the picture of your insides (like sonar) move faster in squishy or liquid things. So if we didn’t use the jelly when they hit the air it slows them down A LOT and they aren’t strong enough to get back to my “camera” to make the picture. For some reason it’s always pediatric patients that ask about the gel, haha.",
"I don’t know what it does but when I was 16 I thought there was something wrong with my beautiful brown testicles. I went to the ER and the proceeded to wrap my chocolatey beauts in a pristine white towel and lather them up with the gel. 25 now and oddly into warm things on my jellybeans. Damn you American Health care for alienating me.",
"Sonographer here: it is a medium so the sound waves can travel from the probe into your body and back again. Ultrasound waves don't travel through air/gas that well. Added bonus of being a lubricant too so you can slide the probe around easier"
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f9sjg2 | How does computer memory just erase? | Technology | explainlikeimfive | {
"a_id": [
"fiti22g",
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"text": [
"(For dumb historical \"computer people are bad at naming things\" memory is actually different than storage, but you clearly mean storage so I'll answer for that) Most devices delete things a simple way: they just mark a file as deleted without doing anything and it stays exactly where it is exactly the same, but since it's marked deleted the next time the computer needs to write something it feels free to just write stuff over the old file. Because of this you can \"undelete\" files for a long time after deleting them using special programs.",
"The file is an arrangement of the storage elements (magnetic domains, flash cells or what have you). When you change their arrangement again, [the old arrangement just ceases to exist]( URL_0 ). Most file systems will not actively perform rearrangement when you delete something, just mark the space as available for use in their index. Then when a new file comes along, the storage elements may be rearranged to remember its information instead."
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f9u56k | How does the “Compass App” work on the iPhone when the phone is electronic? | Technology | explainlikeimfive | {
"a_id": [
"fits0aa"
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"text": [
"The phone contains a [magnetometer]( URL_0 ), a device that detects magnetism, just like an actual compass."
],
"score": [
25
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[
"https://en.wikipedia.org/wiki/Magnetometer"
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f9uw3y | What is a virtual network and a VLAN and how are they different? | Technology | explainlikeimfive | {
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"fitxjik"
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"text": [
"I will give an explanation using the widely accepted definition of these terms, but they are often exchanged. VLANs connect physical clients together as if they were in a LAN, even if they are in different locations and on different physical networks. Virtual networks connect Virtual Machines together in a completely virtual environment where both the clients and network are virtual."
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f9vha6 | how, if at all, would people set alarms for themselves before the traditional alarm clock? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"A knocker-up, sometimes known as a knocker-upper, was a profession in Britain and Ireland that started during and lasted well into the Industrial Revolution, when alarm clocks were neither cheap nor reliable, and to as late as 1952. A knocker-up's job was to rouse sleeping people so they could get to work on time. URL_0",
"Working/poor people rose with the sun or animals (the light or noise would start their day). Middle class to rich people could actually hire people to sit up all night and wake them at a certain time.",
"Before the invention of the alarm clock, and electricity etc, because we continuously lived in natural light, or an orange glow from fire/candles it meant that our body lived in a more natural circadian rhythm, or sleep-wake time, that would fall in line with sun rise and set. After the introduction of Artifical Blue light, that supresses the production of melatonin, has made it harder for us to live by the sun cycle, because our body doesn't know the cycle anymore. If you spend a week in the wild, away from all Artifical lights, Phones etc, You will start sleeping in line with the day-night cycle of the earth. :)"
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f9ymb8 | How does each individual pixel know which colour to represent | I understand the basis of how a single pixel works, but can't work out how you deliver a specific and exact signal to every single tiny RGB block out of the 2 073 600 existiting in a typical 1080p monitor. I there individual wiring going out to each one, and if so how are the signals timed and sent out? | Technology | explainlikeimfive | {
"a_id": [
"fiuqmhj"
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"text": [
"Each pixel is actually 3 sub-pixels of fixed color. The computer sends the brightness to each of these 6M sub-pixels at a rate of 60 times per second to drive your monitor."
],
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5
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fa0kdx | How was music and sound added to movies before computers? | Technology | explainlikeimfive | {
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"fiv2g86"
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"text": [
"In the case of film recordings, they would use an extra strip on the side of the frame that's black, with the audio 'carved' out of it, like [one of these two examples]( URL_0 ). A light is shown through the strip, which is picked up by a light-sensitive amplifier, the output of which is sent to the speakers."
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fa3pik | How did Selectric typewriters associate keyboards with changed globes? Were there charts or what? | Technology | explainlikeimfive | {
"a_id": [
"fivp99q"
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"text": [
"The globes would always have the same letters in the same place, but with different fonts. So when you pressed A on the keyboard, the same particular region of a globe, any globe, would be pressed against the ribbon and paper."
],
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fa7fv1 | Why are there so many different image formats (JPG, PNG, etc.) on the web? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"Short answer: for historical reasons Long answer: That's not necessarily a bad thing since the widespread ones each have their own purpose.",
"Because no single format is the best for everything, There are differences in filesize, quality, method of image creation, color space, transparency, animation, compression techniques, compatibility, etc. For a company logo, it would be a terrible idea to use jpeg, a vector format like svg would be far better. For a photograph, you might use png or jpeg, depending on your quality vs size tradeoff. For a loading animation, you might use gif."
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fackh6 | How does HD Radio work? | Technology | explainlikeimfive | {
"a_id": [
"fix5cka"
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"text": [
"HD radio uses radio frequencies just above and below analog signals to retransmit the audio radio signal in a digital format, while maintaining the analog signal for original radios. Because the digital signal is transmitted as binary data (on or off), there is less distortion compared to analog signals, which rely on the waveform of the broadcast. For people with an HD Radio, it means they can listen to the exact same broadcast with less static, crackling, and distortion."
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fae6gb | How do microphones in live concerts not get a lot of feedback from all the noise? | So this might be a super simple explanation, but it really amazes and confuses me. How do microphones in live shows not get tons of feedback from the speakers, the croud sounds, the various instruments? This really baffles me | Technology | explainlikeimfive | {
"a_id": [
"fixhfle",
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"text": [
"1: use a directional microphone, and don't point it at a monitor or speaker. 2: limit the number of open mics. 3: keep the mics as far away from speakers as possible. 4: use in-ear monitors vs stage mounted monitors. 5: cut out all frequencies outside of 800kz to 2khz.",
"EQ: narrow band filters. Finding the frequency that is feedingback, lower it. Hi pass and lo pass filters. Delay(time alignment): delaying the mic (edit) to a certain speaker, can get you more gain before feedback. (This is usually done with vocal mics) At some point you add to much and it gets weird. Dry up the signal: try not to use reverb. Or very very little of it.",
"Our brains are really good at adjusting for different sound pressure, so what sounds to us like it's just a small difference in loudness can actually be massive. For example if you want your speakers to sound twice as loud, you actually need to increase the power from your amplifier about tenfold. A tenfold increase conveniently means ten decibels more as well. Our brain deals with that by simply drowning out the quieter thing. Music at 70 dB will sound loud in a quiet room, but you won't even notice that there's music if you turn on a vacuum with 90 dB because it's a hundred times as powerful. The same thing happens with difference microphones on stage: Because the microphones are close to whatever they are recording, its sound will drown out the others. On top of that, they use microphones which are directional, so that they don't record sounds coming from the sides as much."
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faegse | How did the Game Boy (and similar) battery indicators work? | For those who don't know, the Game Boy had a little red light bulb that would shine bright when the batteries were full, but would start dimming as they run out of power. Was this purely electrical, or was there some computing involved? I have a pair of modern (AAA-operated) headphones that do the exact same thing, do you think the solution is still the same? (I'm actually interested in how this type of lights worked at all, but the Game Boy is an easy example) | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"If it was an LED the light decreases as the voltage drops bellow the ideal one. Batteries decrease in voltage as they empty. Its not very precise but it works."
],
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fahhnw | How come you can still move when lagging but it teleports you back? Also, sometimes it gets to the point where the game won’t let you move? What’s the difference? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"Basically, your system (pc, ps, xbox, whatever) thinks you're still doing everything properly, but when the network sends a signal telling it where everyone is/should be, your system takes that info over what's already on your screen and bumps you back to correct it.",
"You are constantly sending data to the server, which processes it and sends it back to your system. When you are lagging, you move forwards and send a signal to the server to update your position on the game world. However, if the signal gets lost or reaches the server with a high enough delay, your system will sense it didn't get an updated position from the server and therefore revert you back to the last known position to have been validated by the server",
"Client server games have to make some choices when coordinating where your character is on the screen vs on the server. It takes time for your client to communicate with the server, and additional time for the server to send updates back to your client. Your client sends updates to the server as you move your character, but in order to not be extremely jumpy in the \\-(you move your character) \\-(your client sends the move to the server) \\-(the server acknowledges the move and sends back the okay to the client) \\-(your client displays the acknowledged change) process, your client assumes that the server is accepting the changes as it sends them. In the case of lag, some of the things your client sends get delayed, and sometimes sent all at once... Sometimes the server has limitations on how much movement can happen (in order to keep hackers from sending data too fast and \"speed hacking\" or teleporting) so the server might refuse to accept some of the actions sent by the client (resulting in teleporting you back) Sometimes, the client will only allow so many actions to be performed without being acknowledged by the server before displaying the movement on the screen, resulting in the second phenomena you mentioned where you reach a point where you can't move anymore."
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fakkzv | What does "cabels" mean in WikiLeaks and Assange related articles | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"It just means \"messages\". The term is a holdover from back in the days when these messages were sent out as telegraphs over actual electrical cables.",
"Cables are diplomatic communications > Description A diplomatic cable, also known as a diplomatic telegram (DipTel) or embassy cable, is a confidential text-based message exchanged between a diplomatic mission, like an embassy or a consulate, and the foreign ministry of its parent country. A diplomatic cable is a type of dispatch.",
"The United States diplomatic cables leak, widely known as Cablegate, began on Sunday, 28 November 2010 when WikiLeaks ( a non-profit organization that publishes submissions from anonymous whistleblowers) began releasing classified cables that had been sent to the U.S. State Department by 274 of its consulates, embassies, and diplomatic missions around the world."
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fal6dp | What is the hype surrounding 3D printing food? | Don't you need food to 3D print the food? It seems like all the hype shows that we can just make all of these magical foods out of thin air. For example, when 3D printing with plastic, you still need the plastic strings(?) to make layers that form the shape. | Technology | explainlikeimfive | {
"a_id": [
"fiyttzx",
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"text": [
"3d printing food doesnt work by miceing up food to be printed. Instead, meat is syntetically grown to be 3d printed. Thats why its more interesting.",
"The idea is to grow beef muscle cells in a tank, and then feed them through a tube into a print head that puts them in a steak pattern. Then you cook and eat the steak. Cows consume a huge amount of resources, and are very inefficient at converting their input food into human food. Plus they burp out a gigantic amount of methane, a greenhouse gas 25X more problematic than CO2, like 3B tons per year for all the beef cows out there. If a 3D printed steak was cost competitive and taste competitive (it's not either today) it would be a super awesome thing to introduce."
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falen8 | why can’t a CNC router work like a roomba? | I mean, why can’t the router travel across the item to be cut on treads or wheels instead of having to be mounted above the item on a gantry setup? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"There are multiple problems. The main is how to stay still when you cut. The forces involved are very high and you want close to zero vibration. So it needs to be very heavy so it is held down by gravity, magnets or attached to a frame that the object like it is done today. The precision has to be a fraction of a millimeter The second one is how to handles edges and areas you have cut that is uneven. Any system that can handle uneven surface and hold it selfe down with magnets etc would be more complex and expensive than a traditional CNC machine- It gets worse for 4 or 5 axes CNC was the object you cut can rotate in one or two axis There exist stuff like what you ask about but it is cutting and drilling tool for construction machines. You need to be at that size to be stable and work with a lot lower precision",
"Have you ever tried to precisely drill into something without having center punched it first? If so, you'll know that drills don't actually stay nicely in your hands. Making a hole in precisely the place you want without help is *hard*. The drill starting to spin applies a force. And the point likes to dance around on a smooth surface. And that's the best case scenario. If you've used a drill enough you'll also have ran into situations where the drill grabbed the work and nearly (or actually) pulled itself out of your hands. So some sort of roomba with a cutter attached to it isn't really practical for almost anything.",
"Accuracy requires rigidity, so your robot would have to be extremely heavy, and have some way of accurately determining its position. Also, what happens when you drive on top of sawdust or chips? your traction and positioning both go out the window. What if you want to turn the whole piece into a contour map? What is the robot going to be driving on at the end of it?"
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fan26m | How does my water softener work? | Technology | explainlikeimfive | {
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"text": [
"**Water softeners work** through a process called ion exchange which eliminates calcium and magnesium from the **water**. When the hard **water** enters into the mineral tank, it flows through a bed of spherical resin beads. ... When the bead seizes the mineral ion, the sodium ion is released."
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6
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fatc8c | What are the differences between QLED, UHD, OLED, HD, LED etc? | Technology | explainlikeimfive | {
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"text": [
"HD and UHD are resolutions. HD is high definition at 1280x720p, UHD is ultra hd at 3840x2160p. The other terms are names of technologies for the panel creation of monitors/tvs. A different technology means that 1 pixel (1x1 resolution) is created in X way and every technology has its own explanation as to how it is created, how it works, pros and cons, etc. Lets take OLED. The brightness of the pixels of OLED panels comes from every pixel by itself, thus black color can be reproduced by just turning off the pixels where the black is. LED has a backlight which is on constantly, even for black pixels and that is why even though the screen might be black, when its dark, ypu can see the screen glowing. On an OLED, a fully black screen wont be glowing in the dark."
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fauzh4 | What is high and low fidelity in music? | Technology | explainlikeimfive | {
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"text": [
"Fidelity is a measure of how closely a copy matches its source, regardless of the medium. Record albums, JPEGs, DNA -- anything that makes copies has a measure of fidelity, of how precisely it matches or doesn't match the original. The higher the fidelity of a recording, the more similar the sound from the recording medium is compared to the original sound. An example of a high fidelity copy would be a studio master. An example of a low fidelity copy would be an MP3, in which details have been \"smeared\" into groups of similar details, making a less detailed file that still contains the basic waveform shape changes that characterizes that particular noise. Information has been removed, but the overall gist remains the same. A zero fidelity copy would be a recording that sounds totally unlike the original. Like, you recorded a pop singer in the studio but your sound file is the noise of a garbage disposal. The correlation between source and copy is so low it is difficult or impossible to see the connection between them."
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fav5r0 | Why do computer keyboards have the QWERTY design vs alphabetical order? | Technology | explainlikeimfive | {
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"text": [
"More frequently used letters are placed where its naturally easier to reach from the home position.",
"In the first versions of typewriters you would be pushing the key to activate a lever with the letter on it and it would strike the paper. The problem was the levers would get in the way of other levers. So this was solved by placing common used letters far apart from each other."
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favv2y | How do guitar pickups get the strings sound? | Technology | explainlikeimfive | {
"a_id": [
"fj0kmfh",
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"text": [
"Inside the pickups are magnets wrapped in coils of wire with an electric charge running through them. Those magnets are what \"pickup\" the vibrations",
"Magnets. It works in the same way that moving a metallic object (the strings) near a magnetic coil (the pickups) generates power fluctuations (frequencies) in the copper coil wound around each magnet in the pickup. These can then be passed onto the amplifier and played through a speaker. Speakers/amplifiers work in the reverse way, using electronic frequencies to make a magnet move on a diaphragm and generate pressure waves in the air that you perceive as sound. Essentially the pickup translates the vibrations of the string into electronic frequencies that the amp translates back into vibration."
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faxobj | How do people capture these breathtaking pictures of galaxies after (x) hours? | Technology | explainlikeimfive | {
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"text": [
"The telescope is mounted on a multi-axis motor so it can follow the target as the Earth rotates. Then it's just a matter of trying to pick a time and place where light pollution isn't obnoxious. The final photos are then often processed a little to enhance contrast and dull the effects of local light pollution."
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fb0638 | 3D printing still blows my mind. How the hell? Can you choose materials or is it always the same material? You just design on a computer and the 3D printer makes it? How the hell any of it? | Technology | explainlikeimfive | {
"a_id": [
"fj1eoki"
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"text": [
"Short of some very high end systems, 3D printers always use one material, typically a plastic of some kind. As to how it actually works, a few quick YouTube videos should illustrate it nicely. The nozzle squirts out a bit of plastic as it moves around building up layers of material that harden into the object."
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fb1o15 | how do isp's sell your data and why | Technology | explainlikeimfive | {
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"text": [
"It’s incredibly useful for anyone interested in marketing anything, tells any company interested in the data exactly who their target audience is.",
"As of 2019 they could sell \"non-identifying\", haven't checked since. But data is useful to targeting adds, even if it's not directly identifying."
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fb36zk | Why are paper receipts still a thing in 2020? | Technology | explainlikeimfive | {
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"text": [
"Because I don’t want to get spammed for the rest of my life because I bought one thing once at one store Edit - a word. I am drunk",
"Because you can take away a proof of purchase without giving the shop any of your personal details.",
"Because of the marketing practices of companies who not only spam you with their products, but they also sell their databases. You buy one bag of chips and suddenly you're receiving ads from a prince in Ethiopia offering you a million bucks if only you transfer him 1k. Also, lack of education. Many workers and clients, and even business owners tbh, are virtually ignorant to IT advances, and thus resistant to use it. They just don't want to bother to learn new stuff."
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fb6e5p | Why are Bluetooth pairings/connections sometimes dodgy unlike wifi which almost connects instantly? | Technology | explainlikeimfive | {
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"The two technologies work in completely different ways and are optimized for different purposes. With WiFi, you have an access point which is normally wired to a power outlet. It is continuously broadcasting its presence to anyone listening - about 10 times per second. The only thing a device has to do connect to it is look through all the channels until it finds the access point, then connect. It only has to spend about 1/10-2/10 of a second on each channel seeing if it finds an AP, so this can go pretty fast. There are 13 WiFi channels in the 2.4GHz band. If you're always on the same AP, it's likely the device will know what channel to expect it on to make the process faster. Once the device finds the AP then the connection process is quite fast (just a few packets of data quickly exchanged), if everything is working smoothly (though some routers and other WiFi APs are slow). Bluetooth is designed for connecting between low-power devices, so it works differently. Bluetooth devices aren't transmitting all the time. They aren't even receiving all the time, as even that would use too much power. Instead, Bluetooth devices \"wake up\" periodically, every 1-2 seconds, and see if anyone is calling out their name. They switch channels every time, and there are 32 possible channels. Since Bluetooth is a lower power technology, it relies on switching channels constantly, avoiding noisy channels - but this only works after devices are connected. Initially, you get a random channel that changes every second or so, and if you get a bad roll of the dice, it can be too noisy for the connection to work, so you get to wait. And the device that is making the connection has to transmit constantly until it \"catches\" the receiver turning on and listening. And that is just for actively connecting to an existing device. If you're scanning for devices it's worse. That said, it's entirely possible for Bluetooth to be fast and WiFi to be slow. It depends on the exact specific situation, the devices involved, how noisy your RF environment is, etc. It's also entirely possible that your problems are caused by outright bugs or problems with your devices.",
"Bluetooth requires less power, emits less powerful signal, while wifi creates higher frequency so needs more power to connect, in turn making a more powerful signal."
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fbf54c | How do colorblindness fixing glasses work? I know our eyes have cones that detect different kinds of colors, so how can they see colors that they don't have receptors for? How do these glasses help the color receptors detect colors they've never seen? | Technology | explainlikeimfive | {
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"text": [
"These glasses can help people with colorblindness see more accurately, but they do not perfectly replicate regular vision. Colorblindness can have different root causes. For many people, it isn't that they don't have the receptor, but rather that it is over sensitive. This, pr they are missing a receptor in the middle of the red-green range, making it harder for them to distinguish the difference. Most common with the red and green cells, there is an issue where some wavelengths of light overlap, triggering multiple receptors incorrectly. This prevents people from seeing the actual color of the light. These glasses filter out some of the wavelengths of light that commonly overlap. This allows the colorblind wearer to see the colors more accurately, since the brain is less confused over what it is seeing. As for the reaction in the video, probably that is attributed to over exaggeration for views.",
"Red/green receptors are sensitive to similar wave lengths: 534nm is optimal for green, 564nm is optimal for red. For people missing one type of photoreceptor, both colors are picked up by the same receptor nearly equally making it so they look about the same. Colorblind correcting glasses block out a middle band of the light forcing a differentiation. Colorblindness correcting",
"They don't actually fix anything, but they do give additional perceptual color separation and differentiation so that an otherwise color deficient individual can see the differences. Source: Am an Optometrist"
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fbih6t | How are companies like amazon able to allocate so much hardware for cloud storage? | I've been working with amazon aws and I'm confused how amazon can possibly have enough hardware to handle all it's customers and users. I was reading one of the benefits of cloud storage is that there's no hardware maintenance for the user and no need to upgrade every X amount of years. Wouldn't amazon run into the same issue? Wouldn't they need to update their hardware every X years and wouldn't it cost millions of dollars? | Technology | explainlikeimfive | {
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"text": [
"Amazon can afford it because of their scale. Amazon gets massive discounts on everything HDD CPU's ect because they don't order 100 HDD they order 100,000,000. Also look at the costs of S3. S3 is 0.023 GB a month. Lets assume Amazon used WD Gold 14TB HDDs. You can pick one up for about 460$ I'm not sure what Amazon pays bout I would say 400$ is totally reasonable it's probably even lower. Including raid 6 on a 8 disk array lets you use 75% of the disk or 10.5TB. At the s3 rate this is 241$ a month. The WD Gold has a 5 year warranty so assuming it dies at exactly 5 years Amazon can make 14,490$ on a disk that cost them 400$. That is a profit of 234$ a month, for every HDD! This doesn't even count your read wright costs. This is where scale comes in. The other costs like the data centers and IT people can be spread out over all the Amazon cloud products so that maybe only 10 or 12 dollars of that HDD profit are spent on IT people and another 8-10 are spent on the data center it's self."
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fblnjt | Why is Mozilla Firefox a more secure internet browser than Chrome and others? | Technology | explainlikeimfive | {
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"text": [
"There's a difference between security and privacy. A house with nothing but glass and metal bars, with a lot of guards outside is quite secure, not private though. In security chrome and Firefox are equivalent, though Chrome may have the edge (no pun intended) because it isolates itself from the rest of the system. Privacywise it's a nightmare because Google profits depends on how much it knows about you, as they will use it to sell stuff to you or help other companies do so for money. Every product of theirs is designed to gather all the information it can, so imagine how much information a browser, in which you spend most of your time, will gather. And this is a problem for 4 main reasons: 1. One person having that many data is too much power 2. That information can be used to manipulate you (with political propaganda and ads) 3. That information can be demanded by the government which can use it against you 4. If it leaks that information can be used to do harm to you (stalk you or steal your identity). Most browsers, aside from Firefox, use Chrome as their base to build upon. The guys from Firefox get paid regardless of what they know about you and build their whole market around privacy."
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fbly0e | Why do LED headlights flicker when being viewed through a camera or recorded video but not when you look at them with a naked eye? | Technology | explainlikeimfive | {
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"text": [
"Pulse width modulation: keeping LED's on for a short burst, and off for a short burst (usually shorter off times) to save electricity, reduce heat output, and create a 'dimming' effect for LED's, because LED's can't be dimmed by lowering voltage. So when an LED is on a PWM circuit, and a camera records it, the light will blink on the recording/playback, because the LED is blinking at a different rate that the camera shutter speed is capturing the video. If you have the ability to 'shake your eyes (see 'nystagmus') you can see the effect IRL, or if you look toward, or away from a set of taillights of cars that have this effect (Cadillacs have, im my opinion, the best viewing ability for this effect) you'll notice in your peripheral vision dots or dashes of light (depending on how fast you adjust your gaze)",
"If something flickers with a high enough frequency your naked eyes won’t see the flicker. That’s why you can see movies with 24 frames per second."
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fbqdun | How does the real-time ray tracing work in the computer 3D graphics? | I have been hearing about the new types RTX graphics cards that can do ray tracing real time. I know how the light radiation works in real life and previously -unless you wanted a still ray traced image that took long time to calculate- you had to use computer trickery to render effects that simulate in moving 3D. Now with the new RTX-type graphics cards how close are we to how the real light works in real-time computer 3D space? Just how does it work? | Technology | explainlikeimfive | {
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"text": [
"I've written a longer answer to this before, but here's a summary: traditional ray (and/or path) tracing is slow, because there are so many rays to simulate and the simulation of an individual ray is slow if the scene has a lot of complexity. RTX-style ray tracing improves these in 3 ways. - The GPU is used for ray tracing instead of the CPU, which works because GPUs are designed to do thousands of computations at the same time. - Individual ray simulation is made faster by dedicated hardware on the GPU that can be used to quickly test which objects and rays can intersect, which usually takes a lot of time. - The number of required rays can be significantly reduced with the use of state of the art denoising and resolution scaling algorithms. Normally a ray tracer needs to simulate many rays per pixel to get a good result, but with denoising one ray (or less) can be enough."
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fbxl27 | Why do some programs & games open quicker when you recently closed them? | Sometimes you quit a game and then open the game again after 30 seconds, it loads a bit faster than the time you load it for the first time in the day. Similiarly I find it to be the case with some other applications. Why does that happen? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"Operation system caches some data. It makes an assumption that if program was recently used or is used regularly, then it makes it more probable that they will be run again in the nearest future. So it has some files relevant to this program easily available, which allows to omit some operations usually performed at the startup, which saves time."
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fc2wta | Why do most smartphones need to use headphones as an antenna? What makes FM radio waves hard to catch without it? | Technology | explainlikeimfive | {
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"text": [
"FM radio has a wavelength of between 2.5 and 3.5 metres. An antenna half that wavelength is pretty efficient in receiving the signal, and earphone cables are roughly about that length, so get used as antennas, as well as carrying the sound signal from the phone to the earphones.",
"Your car radio has an antenna as well, as did TVs before cable. Your smart phone doesn't have the space to put in a coil or a long loop of wire, so it uses the headphones, which are handy.",
"It is already answered here so I'll just add and answer your second question: > What makes FM radio waves hard to catch without it? Your phone has an antenna that is few centimeters long. In order to catch a radio wave you need an antenna at least half of the size of the wave. And since FM radio waves are big, they need big antenna - you can imagine it as an FM wave \"jumping over\" your phone's antenna and the antenna not even seeing it.",
"Radio waves induce a small current in a conductor, this the entire basis of radio communications. The bigger the conductor (the antenna), the more radio energy it catches, and the greater the current. The greater the current, the less the signal needs to be amplified and the less prone it is to interference and distortion."
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fc42at | How does smart devices like Alexa, Google Home, and other devices not “listen” when you are talking without saying their name? | Technology | explainlikeimfive | {
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"If I'm correct the microphone is always listening. It's just in some sleep state waiting for their respective trigger word to turn on the transmitter and recording device. From what I understand the microphone is never truly off. So until you say the trigger word like \"hey Google\" the machine keeps its recording device off",
"They do listen, else you wouldn't be able to unmute them without a physical switch. They just discard anything you say while in muted state and (ideally) don't transmit or evaluate that information in any way, except for looking for the \"unmute\" command obviously",
"They are programmed to listen to specific keywords. You can buy these chips preprogrammed with a set of keywords for development purposes. URL_0",
"Like others said, they are always listening. The trigger words are recognized offline. After hearing the trigger word they send the recognized words to their server to get the meaning, as the on board recognition is not smart enough.",
"They do listen. They’re waiting for “wake up words” that cue them to turn on. Sometimes it’s a miscue. A study using various TV shows (e.g. The Office) - I believe by MIT but I may be mistaken - found that words similar to “OK Google” and “Alexa” would wake up the devices several times. The snippets they collect, which you approve of sending by using the device, are sent to offshore contractors to determine if the algorithm they use is working. (I work in cybersecurity and privacy, have studied them for a while. We don’t allow them in our offices for this exact reason.)",
"Ostensibly the way they work is that there's an initial listener system on board the device that is always listening and performs word-recognition looking for the \"Alexa... Hey Google... etc\" trigger words. Once that trigger has been found, the rest of the audio stream is passed on to the online systems for full parsing. If the trigger word hasn't been detected, the audio is just overwritten/deleted. There's lately been a fair amount of doubt that this is exactly what is happening though.",
"Some comments have satisfying answers but to be elaborate - Generally voice processing(voice recorded by your mic) or text to speech conversion is done at cloud (far away computer) but it simply can't handle the load of everything you say to find the \"trigger' word , so they have a special system(both hardware and software) inside your device to listen only for that trigger word once the trigger is encountered it starts transmitting the data to cloud where it will be processed and results will be retrieved.",
"There has been some lack of clarity on the 'always listening' part. The devices aren't transmitting data over the internet. The devices are able to detect the trigger word, which tells them to start sending your voice over the web. A reason you can trust that the companies won't purposefully send everything you say is that without any extra equipment, people can monitor when the smart devices use the internet, and how much data gets sent, so they can basically see when the device is active",
"It does always listen, it just doesn't store what you're saying long term, there's only enough memory for a buffer so it can always check for \"Alexa\"",
"Wowzers, there is a lot of tinfoil hat theories in here! These devices run a short listening loop. Always recording like 5 seconds and continuously dropping anything longer than 5 seconds. when the correct sound is inputted into the microphone the device begins to record your query to send back to the server for response. Saying \"hey Alexa or hey Google\" is equivalent to clicking \"file - > open\" with your mouse.",
"Imagine there's a loop of recording material that will record for 30 seconds. Every 30 seconds, it runs out, so it erases and starts recording over the same spot. The devices always record to that 30-second loop. BUT, if it hears its wake word, it moves that part of the recording to another spot to send \"home\" (to Google/Amazon/Apple/Microsoft/etc.) to analyse and get a response for you. At least, that's what is *supposed* to happen. But every service randomly (or not-so-randomly) selects some of those devices to send the 30-second snippets to one of their analysis centres, where live people can listen to what's been recorded. And there is almost no security on those recordings whatsoever. Smart devices hear everything you say and do, and you never know who is listening."
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fc57fc | how is LED different from an incandescent? | And why did it take us so long to come up with it? | Technology | explainlikeimfive | {
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"text": [
"Incandescent bulbs heat a filament, or wire. That wire creates light from the heat. Think of a heater or stove glowing when it gets hot. The same thing is at play here, which is why incandescents get very hot. LEDs run power through diode, or a place where electrons like to play. The power excites these electrons in the diode and when they play, they make light. Not a whole lot of heat in this process and is much more efficient."
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fc5pdt | How does a touch screen detect touches under glass? | It's like magic, how do it work?? | Technology | explainlikeimfive | {
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"text": [
"It measures capacitance. Your finger is conductive. The \"glass\" is non-conductive. There is a layer of transparent conductor under the glass. Wherever your finger touches, a capacitor forms -- an area capable of holding an electric charge. By reading the capacitance of each area of the screen, it can determine where it is being touched. This is why non-conductive object such as styluses do not register as touches."
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fc6bwn | how does this work? (Link in comments) | Technology | explainlikeimfive | {
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"text": [
"Put the camera on a tripod. Then take a picture. Advance the film and stand in one place. Then take another picture. Advance the film and stand in the next place. Then take another picture. Advance the film and stand in the third place. Then take another picture. Not you have four pictures with the needed parts of the scene. You can make masks for the \"background\" using a negative print of the background. Then print the background, followed by each of the other poses on the same piece of photo paper. This sort of thing was a routine part of darkroom training, back in the days of B/W photography."
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fcb1jv | How do those "I am not a robot" reCAPTCHA's work? | Technology | explainlikeimfive | {
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"text": [
"The ones that are \"just a checkbox\" are a little bit spooky. They leverage Google's awareness of your behavior \"before, during, and after\" you click the box. It checks your browsing history, mouse movements in your browser, and other factors to see if it think you're a person. A person will have natural browsing habits (checking email, going to youtube, reading reddit) as well as moving the mouse in an organic way If it isn't SURE you're a human it can still give you a real catcha to check (the choose a picture thing) Try visiting the same website with your normal browsing habits and then again in a new, incognito window, and the catcha might treat you differently. & #x200B; *(The spooky bit is, uh, how much info is google watching before you even went to the website with the recatcha?)*",
"There are bots that can. But they all follow a rather predictable pattern - they zoom right to the box, no dallying or random shaky mouse movements. Making a bot that moves the mouse like a human is considerably harder than making a normal bot, so those boxes make it much harder to do at the very least",
"There's lots of good responses already but I will add something I haven't seen. Many of those \"Check a Box\" things are strategically placed so that they are not actually on the page when it loads. You'll notice 9 times out of 10 that you actually have to scroll down to see it. If you instantly clicked the box then it would set off a flag that maybe you aren't human. In that case you might get another captcha.",
"I suggest listening to [this Radiolab episode]( URL_0 ). It's about 25 minutes long and tells the history of the system. It's actually quite interesting why it came about and how it has evolved."
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"https://www.npr.org/sections/money/2019/04/24/716854013/episode-908-i-am-not-a-robot"
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fcbjiz | How do radio stations know how many people are listening? | Technology | explainlikeimfive | {
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"text": [
"The [Portable People Meter]( URL_0 ) is the modern way; however, in the past --and possibly even today in some smaller markets without PPM technology-- a diary system was used. People would get a call from the ratings company Arbitron asking if they wanted to take part in a radio survey. If the person agreed, a few weeks later, a package arrived in the mail. The package included a diary for the participant to log their listening habits. Radio ratings were compiled based on several factors and then broken down into various demographics. Anyway, this [diary system]( URL_1 ) was the reason why radio stations used to identify the station so much. They wanted to make sure people, particularly those with diaries, remembered which station that had listened to during the day. Source: former radio program director",
"Nielsen ratings. The Nielsen research group pays a certain number of homes to install boxes on their TV's or radios that will send information back on what's being watched or listened to. They use statistical averages to determine that for every 1 household listening to a certain a station, it counts as 1,000 households. Those numbers are made up for this explanation.",
"There is no absolute way. But generally ratings are gotten by asking people and by things like running contests and seeing how many responses are gotten and having standard ideas of like \"if X people call in that means we have roughly at least Y listeners\""
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"https://en.wikipedia.org/wiki/Portable_People_Meter",
"https://www.google.com/search?q=arbitron+diary&sxsrf=ACYBGNTyaISAEXqhuWVUfsujsUv7e6hd4g:1583158059106&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiB0fGt-_vnAhVgkHIEHXxcCLIQ_AUoAnoECAwQBA&biw=1440&bih=789"
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