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flvqdi
|
How is erasing coded?
|
Moving something to the trash bin in the real world makes sense. You put a banana peel in a compost bucket, it breaks down, and it’s constituent parts are recycled into new parts of soil. I can gather that if there’s a limited amount of data on a computer, moving something to the trash bin is sort of like the recycling of data in the broad sense. But what about the constituent parts? Where do the letters and pixels “go”, and what do they break down into? What has me stuck is that if it were true recycling, the components of a deleted file would be turned into more data, but if deleting something frees up data, that seems impossible. Help?
|
Technology
|
explainlikeimfive
|
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"> Where do the letters and pixels “go” Nowhere, at first. Deleting a file just marks that file’s area of memory as free space. If new data needs to be stored, the OS can now overwrite the deleted file’s memory with the new data. Until the space is overwritten though, the original file’s data remains in that area of memory. It’s just no longer associated with a file, so it’s mostly inaccessible to the user."
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flwa96
|
Why can't you see pixels on a phone screen as easily as you can on a monitor?
|
Technology
|
explainlikeimfive
|
{
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"Say you have a phone that is 1080p and a monitor that is also 1080p. You have the same number of pixels, but they are closer together on the smaller screen of the phone.",
"The size of the display and the resolution. A phone screen is typically 1080p or higher now, same with most monitors. Mobile display density is a lot higher, while monitors are typically not as high. If a display is 1080p, its 1920x1080, equating to just over 2 million pixels. If you stuff all of them onto a phone, it’s going to be a lot sharper. Imagine taking a chunk of play doh. Make it roughly the same size of your phone screen, and it’s going to be a lot dense and thicker. Make it the same size of your monitor display, it’s going to be thinner."
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"url"
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flzwob
|
Why do downloads slow down as they near completion?
|
I've always wondered why this happens. You're downloading a game at 25mb/s up to 98%, then the next 2% drops down to 5mb/s. Does anyone know why this happens?
|
Technology
|
explainlikeimfive
|
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"Modern programs like Steam etc. download files in chunks from multiple servers to fully utilize your connection's available bandwidth. However, not all chunks might be available right away or certain servers might be overloaded for certain chunks. These chunks are left for the very end of the download thus resulting in the slower speeds.",
"In addition to other answers, I just wanted to add that apparently, and this is just me searching to see why my files were slow, smaller files transfer slower than larger files. Could be that each file needs to be prepped first, so there's more prepping for ten small files than for one large file. Either way, they're slower, so it could be that towards the end it's sending a bunch of smaller files. Hopefully this is allowed, since I'm not too knowledgeable on this. Just what I found with some searching a month or two ago."
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fm5ljm
|
- how come older consoles (NES era) were better at games than PCs at the time?
|
PC’s today are at the forefront of gaming and are usually seen as superior to consoles. However, this wasn’t always the case. In the NES era there were PC ports of popular games such as Mario, Mega Man etc. But these ports were inferior to the console release in every way. Is this because the ports were poorly made or was it the lack of processing power of the PCs at the time?
|
Technology
|
explainlikeimfive
|
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"At the time, PCs were largely for business use. They usually didn’t have a lot of graphical power or good sound cards. Consoles were made specifically to run games, so they focused on those.",
"I don't think they were. The Commodore 64, Atari ST, ZX Spectrum, BBC Micro all had fantastic games. I never remember being overly impressed by NES at the time. They seemed more like toys. The SNES was where I remember thinking that things had changed.",
"Our commodore 64 was better at games than any console at that time. However, everyone on commodore pirated games like crazy, so not much incentive to create games URL_0 when compared to Atari selling games for $50 each retail price.",
"it was because the ports were poorly made and rushed, down to the basics, a console is basically a pc that uses a different processor/architecture and operating system. usually due to cost, it's always less advanced than the most advanced pc available at the time. it's a lot easier to optimize something from the ground up than to port it and optimize for a new platform. you never spend anywhere near the original development time/effort on a port, and there are many bad ports throughout gaming history going both ways.",
"There’s a lot more overhead when running a PC compared to a console, even today. The operating system, various drivers, etc all play a major role in efficiency and so back in the day you’re referencing, dedicating a PC to be a console means basically stripping it of every single non-essential element such that only games could be played. As another user mentioned, ports in general fail to compare to the original because one was built ground up specifically for the designed system and another is adapted. It’s to same kind of concept as replacing a door on a car, it will work and do what is expected but your body lines and paint probably won’t match up unless you do a LOT of body work that probably isn’t worth the time.",
"Consoles in the early 80s started having \"sprite\" and \"tile\" graphic engines. They could blit (draw) these elements with hardware acceleration (such that it was) without using CPU opcodes to draw every pixel. For instance, to program mario to be on the screen you need only program a sprite entry to have correct tile and x/y offsets. (a couple of memory writes). Whereas on a PC you would need to write 64 (or 128) pixels via CPU opcodes. Whereas on a PC if you wanted a screen full of moving data you had to draw each pixel with the CPU. Worse, early graphics modes were \"planar\" which meant you had to be really creative. Adjacent bytes of video ram controlled different \"planes\" of pixels (e.g. 320x240 mode X meant a 32-bit write to VRAM wrote out 4 pixels spanning 16 pixels wide). You'd have to change \"planes\" via expensive I/O operations to draw a full screen. Which meant most games would actually render vertically (stay inside your plane, etc). Basically a mess. Many earlier VGA games used mode 320x200 because it was linear (e.g. adjacent bytes represented adjacent pixels) but the perspective was odd (not quite square). tl;dr; early 8 and 16-bit consoles had graphics acceleration in hardware that was superior to what PCs had. Eventually CPUs got so much faster than your console CPUs that PCs caught up in terms of 2D performance. For instance the NES and SNES rocked 8 and 16-bit cpus at a time when 32-bit cpus were coming out (often clocked multiple times faster). So even though a bog standard 486 66MHz PC would have zero graphics acceleration the CPU could perform far more instructions per cycle and those instructions operated on more data (32 instead of 8 or 16 bits). 486 DX and up processors also had a floating point unit that could be used (though most early 3D games used fixed point integer math). Early 8 and 16-bit CPUs would require often 2+ machine cycles to complete a single opcode (operating on only 8 or 16 bits of data) whereas the 486 could complete most simple math opcodes in a single cycle. So a 4MHz 8-bit CPU is doing maybe 1 million instructions per second on 8-bits of data while a 486 is doing 33+ million instructions per second on 32-bits of data. Consoles \"caught up\" again when they too started having mainstream processors and graphics accelerators (GPUs). The GC had a full on 32-bit PPC processor with an ATI based GPU for instance. No more simple tile/sprite engine. As for why PCs didn't have 2d acceleration from the get go ... it's because PCs were largely envisioned as business computers. So high refresh graphics were never the plan. By time gaming on a PC became a $$$ thing we started seeing hardware accelerated blits/etc via BIOS extensions (VBE) and eventually early OpenGL implementations. By this point games evolved past basic 2D primitives so sprite/tile engines never became a PC target (though you could easily emulate them with a couple of tris and a texture)."
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fm69ce
|
When you put two phones or radios next to each other and start a call between then they make a loud ringing sound why is that
|
Technology
|
explainlikeimfive
|
{
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"It is a feedback loop. Basically, there is some noise, be it interference, someone's voice, footsteps, etc. This is broadcast from the speaker of one device at a slightly amplified level. The other device recurved it, then plays it back again at a more amplified level. The two go back and forth like this over and over again, each time raising the volume."
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3
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fm9hyz
|
How are Edm songs made? Specifically how do they generate these sounds in the song?
|
Electronic songs and electronic instrumental, what's the source of the sound?
|
Technology
|
explainlikeimfive
|
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"Producers use digital audio workstations (DAWs) that can emulate the sounds of various instruments -- or just put out \"artificial\" sounds as specified. By adding various effects to the sound -- distortion, reverb, etc. -- they can produce some of the more exotic sports of sounds typically found in EDM.",
"In the 20th century, it was physical synthesizers and samplers. \"Synthesizer\" makes you think of a thing with piano keys but professional ones were mostly little boxes with LCD displays. A sampler basically does what Talking Tom does, but with more things you can tweak. These days, everything is mostly VST plugins; VST stands for Virtual Studio Technology which is pretty self-explanatory. The \"boxes\" are all inside the computer now. And that's why, for example, something as richly textured as dubstep couldn't exist in the 90s. I mean it could, but it would be no fun to make, with the lower computing power and less automatisation."
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fme40m
|
How do electronics know what battery percentage they have?
|
Technology
|
explainlikeimfive
|
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"In short there are two ways, sometimes combined. 1) Measure the battery voltage and compare this against a graph that you obtained through calibration. This will tell you at what voltage, what the battery SOC (State-of-Charge) is. This will not be a linear relation. (being halfway between two extremes does not imply being half charged). Generally this is the *least* accurate way to measure, but it isn't affected by long-term errors. 2) You measure the current going in and out of the battery. You know how much energy a battery will hold if full. Current can describe how much energy escapes the battery every second. Therefore if you measure half the energy has left, the battery is half full. This method is affected by errors over long periods of time, but is much more accurate on shorter periods.",
"Most batteries have a different output (voltage) based on how full they are. For example in a lipo battery (common hobby bats) a charged 1 cell battery will output 4.2 volts, and its \"dead\" when it reaches 3.0 volts. So around 3.6v would be 50% charged. However you can overcharge and over discharge these batteries, but doing that may result in a bad time that usually involves fire and toxic smoke.",
"Voltaje is like the amount of water you have in a tank. If at the bottom of that tank there is a hole the water will start flowing through it and the pressure the water is flowing with depend on the amount of water on the tank, the more water the more pressure you just need to set a sensor (count how much water is flowing per second/time) at the hole to measure the pressure and you will know how much water there is left. Edit: and voltaje is the amount of energy you have on a battery",
"It's an estimate. A clever one based on lots of calculations, but it's still an estimate. Imagine you have a dumb battery cell, and it outputs at a voltage. Say, 5V. That's the only thing you can measure from a battery, is what the voltage is (temperature is also measured for protection against overcharging and overheating). You run your device, and it works fine until the battery gets to 3.9V, at which point it starts misbehaving, and there's a potential to damage the device or lose data. So, the calculation is then done as follows: Voltage 5V = Battery 100% Voltage 4.5V = Battery 50% Voltage 4V = Battery 0% Why not 3.9V? Well, some margin is left between 4V and 3.9V for you to find a charger whilst the battery keeps things like the clock and other volatile things going. It also helps prevent against things like the phone requiring more juice than the charger can provide during start-up, so that it doesn't flake out whilst you're switching it on, things like that. Basically, it's a calibration based on trial and error. Battery calculations are also nowadays self-calibrating, which is why your laptop is able to tell you that it needs a new battery (and why Apple were fined for manipulating phones based on battery stats)."
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fmjmmv
|
When you reset the wi-fi router, why does it take so long to turn on? What happens during that time?
|
Technology
|
explainlikeimfive
|
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"Your router has several hardware components. * Integrated switch (physical network connections) * Wireless RF circuitry for sending and receiving data * Processor and routing software to handle data-link stuff * NVRAM - non-volatile memory - stores configuration information and system software * RAM - stores currently running configuration and copy of system software The router will run a self-test on its hardware when starting up. During this period, it will give out fault codes and other diagnostic information if the system has internal data corruption or other hardware errors. This takes up time. Fun fact - you can actually connect a serial line directly to the board on most routers and observe this in a console. So the memory copy rates aren't all that fast when a router boots up either. This is why, for instance, it still takes a good minute or two to update the firmware after you have downloaded it. After boot, It will copy your firmware / operating system and configuration from NVRAM to RAM. This takes up a good deal of time. Once the hardware tests are passed and the router's software is loaded up, each piece of hardware gets \"initialized\". This is the part where the router looks at your connected devices and establishes connections. Things that are wired into the switch (such as a modem or gateway), checking the current bands and selecting the least congested one, and bringing any other software on the router up (such as a VPN service). There is a lot more going on under the hood than listed here, but this is ELI5 after all. EDITS: Just fixed a couple typos. I also see lots of people making a valid point that this isn't \"ELI5\". Also that a router is \"just a small computer\". The thing is, it isn't just like a small desktop/laptop. It has very specific hardware and software that accomplishes a very specific set of tasks. Unfortunately, this question can't really be meaningfully answered in the framework of ELI5. A 5 year old would just have to accept that it needs time to start everything up and get everything talking to each other.",
"Routers are mini-computers that also can send and receive wifi. The router has to turn on and boot up, just like any other computer.",
"The router itself is basically a mini computer. Just like the computer you use, it has a CPU, memory, storage, an operating system (the \"firmware\"), etc. All of these are of course specialized for its job of handling network traffic. And just like your computer, it needs time to start up after it's been turned off. During that time it does the same sorts of things your computer does when it boots - initializing its hardware, loading the operating system, and launching various software components that allow it to do its job. The hardware on routers is usually quite weak, since they only need to be good enough to perform the one job they are designed for. They run much slower than your computer. So, even though a router is a comparatively simpler device, it may take longer to start up than your computer.",
"Just one thing I'd like to add to all the (otherwise great!) answers: the \"WiFi router\" you're talking about is probably a 4-in-1 device: it's a WiFi *access point* (sends out and receives the WiFi signals, obviously); most often also a *switch* interconnecting several Ethernet ports and the WiFi access point; a *router*, which decides whether to send a packet from your ISP to your WiFi and vice-versa; ans finally, most crucially, a modem which allows it to connect to your ISP. Now in most cases, the slow part is just that last one: access points, switches and (to a lesser extent) routers are often rather simple devices that boot up quite quickly. A modem however, needs to make a connection over miles and miles of cabling, authenticate that connection with your ISP etc. It's quite a bit more specialised, hence why it all takes a bit longer.",
"I can answer this, because I work with routers. Turning a router on and off is similar to turning a light on and off a light build. It should turn on instantaneously. Which it does. But for a router to work, it needs to run programs or software that communicates back to a station. That software is what's causing the router from working straight away. It will send out a command which identifies itself to a station, wait until the station respond, then proceed to continue run everything else which can take some time for the router to process. Boot up time is also depended on it's hardware. So faster chip means faster computation that process the software quicker.",
"Your router is waking up like a nonmorning person- its hair is a mess and it's slow to get moving. So it needs to go to the mirror and see that its hair is a mess then take the time to fix it. Once its hair is fixed and teeth are brushed, it goes out and says goodmorning to the family- Mama Modem and Daddy Desktop, along with any other siblings it may have. Mama has prepared breakfast as always and its your router's job to set the table and pass out the food to everyone. And as much as we all wish food instantaneously appeared on everyone's plates, it takes a little time. . Routers have several components, both hardware and software (physical parts and programs). Your router will check itself for issues when you turn it on. You can watch this process with the right tools! Once the check is passed, it pings the things that its connected to, such as your modem and computer, and tries to connect to them, looking to take internet from the modem and give it to anything else plugged in (such as computer, gaming consoles, etc).",
"The big ELI5 is that a router is designed to stay on for a long, long time so optimizing the time it takes to start up isn't so important",
"When the router comes on it has to contact many government agencies to make sure it's okay that you have the internet back and that they are still able to listen and record everything you are doing on the internet.",
"The router is a small computer. It‘s task is to negotiate all the information that is sent through your network. That requires some specific tasks that are carried out by different modules. And those power up in a specific sequence. Between those steps, there are also set timers, to make sure one step is finished before the other starts."
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fmktz4
|
what is psychological horror?
|
Technology
|
explainlikeimfive
|
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"If horror primarily deals with threats to the body (being murdered, tortured, disfigured, etc.), psychological horror deals with threats to the mind (hallucinating, going insane, being possessed or controlled, etc.) There's obviously plenty of room for overlap in substance, but psychological horror also has a particular _style_. Authors have direct access to their audience's minds in a way they don't for their bodies, so they can do more than just depict violence and gore. They can actually give the audience something of the experience that their characters are having.",
"Psychological Horror is where a story tries to scare the reader/viewer/player with events and descriptions that dont always relate to common horror tropes. Often found in films using background sounds, music and plot twists, without showing anything necessarily scary. It builds up the horror lightly, and can be used to hype up a jumpscare or reveal something scary, and often uses more abstract subjects to scare the viewer, like the use of shadows or the creaking of a floor panel, to make the view think and scare themselves doing it",
"Horror includes many categories. Some major categories are viscerally revulsive, e.g. gore/mutilation; momentary panic, e.g. jump scares; and mounting dread, e.g. the feeling of exploring an abandoned hospital. Psychological horror would fall into the third category. It's not necessarily immediately scary, but the more you immerse yourself in it, and the more you think about it, the more unsettled and distraught you feel. The feeling can last for days, weeks, or even longer after you're done seeing, reading, hearing, or playing the horror story. Nothing scary even has to have happened, necessarily, although often times it does. Tl;dr: Psychological horror gets worse the more you *think about* it, instead of the more you *see* it."
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fmo80g
|
Why are xrays printed on a clear piece of plastic and held up to a light box, instead of just black ink on white paper?
|
Technology
|
explainlikeimfive
|
{
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"They aren't \"printed\" they are a photographic exposure with the \"film\" reacting to the X-rays to produce a negative as happened with cameras before digital cameras existed.",
"Good responses here. Part of it is that a transparent image, lit from behind, can reproduce a *much* finer range of detail, and wider range of brightness, than an opaque image lit from in front...that's why slide projection is popular in color photography. Med students spend a *lot* of time learning how to tell one object from another in an X-ray...every faint, subtle line means something.",
"Former radiographer/x-ray tech here. In the film days, the cassette in which the film was loaded was more than a light-tight box to hold the film flat. While photographic film is sensitive to x-rays, long ago they started lining the inside of cassettes with radio-luminescent plastic, which converted the x-ray energy into photons (light), providing a much lower dose of x-rays' ionizing radiation during the medical procedure. No idea if this trick is still used in the digital realm.",
"The plastic is actually film like an old school camera. X-rays show up on x-ray film just like visible light shows up on visible light film."
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fmpa0k
|
what is that weird sound you hear when you leave a cell phone by speakers?
|
title
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Audio cables, especially unbalanced and/or poorly shielded cables are essentially antennae, and while their primary duty is to carry small AC currents from your sound system to the amplifier, they can just as easily pick up signals out of the air, just like a radio antenna. Your cell phone, by virtue of how it works, is constantly sending out radio signals to cell towers, wifi routers, etc. What you are doing is putting a radio emitter beside an antenna and amplifying it."
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fmvzp9
|
How can I delete an app from my phone and then not have enough space to download it again?
|
I've seen memes about this so I know this doesn't only happen to me. There have been times when I got warnings about not having enough space, so I deleted some apps from my phone. When the warning didn't go away, I tried installing them again and it said I didn't have enough space! Where did all the memory go?
|
Technology
|
explainlikeimfive
|
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"text": [
"On Android, when you delete an app, it often leaves behind data that the operating system is unaware of, so it never gets deleted. The main data files for that app are deleted, but the leftovers will just sit there forever. You can manually search for and delete that leftover data yourself on any Android device. It doesn't need to be rooted to do that. On iOS, this doesn't happen often, but when it does, syncing with a PC/Mac using iTunes or Apple Music or whatever fixes that. Also, the word you meant to use is storage. Memory is something else entirely."
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"url"
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"url"
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fmwvsq
|
Why do storage and memory follow a pattern of 2 (i.e. 2, 4, 8, 16, 32, 64, 128, and so on)?
|
Technology
|
explainlikeimfive
|
{
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"If you have one wire you can address two memory cells number 0 (power off) and number 1 (power on). With two wires you can address 4 memory cells. With four wires you can do 16. If you want 17 memory cells you need to have everywhere 5 wires and use the fifth one for just that one cell. This is not efficient. If you already have the wire in place, why not to utilize all the possible capacity of it?",
"Because computers operate on binary, because they are digital - they deal in absolutes of a particular electrical line either having power or not having power, and nothing in between. Take your fingers. Now, if a finger can \\*only\\* be up or down, and nothing in between, see what numbers you can get up to. With only two fingers you have both-down, one-up-one-down, one-down-one-up, and both-up. 4 combinations. With 3 fingers there are 8 combinations. With 10 fingers there are 1024 combinations. They're all powers of 2 because there are only 2 digital states, on and off. If you have, say, 10 electrical pins addressing a storage device, and they operate in binary, that means you have 1024 possible addresses. If you have 11, that's 2048. If you made a 1000-byte storage device, you'd have 24 bytes that you couldn't access, for no real good reason. And you'd probably need some extra logic or circuitry to refuse access to only those 24-bytes. Notice, also, that the pattern of your numbering is not even the full answer... you're already sending and receiving \\*bytes\\* (which are 8 binary bits), kilobytes, megabytes, gigabytes, etc. The choice of the number of those is a power of two just like the number of bits in a byte is a power of two. If you had analogue computers, it would be different. If you had ternary computers (computers that have 3 states for each connection, i.e. off, half and full), then it would be powers of three (or you'd be wasting some bits, or in this case \"trits\"). Your computers and other devices convert everything - even analogue signals like those going over your telephone cable, microphone, video camera, etc. - to digital information in order to process it. As such everything ends up as some power-of-two. That slightly-red colour your webcam picks up is converted to the nearest RGB equivalent and sent as three digital bytes to your computer. Everything gets digitised.",
"Imagine memory and storage to be a collection of identical looking boxes that can only be identified by a number written on it. The content of the boxes are the things (data) that you store. If you use only single digit numbers, the most number of boxes uniquely identified is 10 - ie from 0 to 9. If you use two digit numbers, then you can identify 100 boxes ie 00 to 99. Because we use decimal (base 10) numbers the number increases as 10, 100, 1000 which is 10\\^1, 10\\^2, 10\\^3 where 1,2 and 3 are the number of digits used. Computers use binary numbers which has only two digits 0 and 1. This means as the number of digits used to identify boxes increases, the number of different boxes identified increases by 2\\^1, 2\\^2, 2\\^3, 2\\^4 which is 2, 4, 8, 16 and so on. Computers use binary numbers because that is easy to implement in electronics where 0 is \"off\" and 1 is \"on\"."
],
"score": [
16,
8,
5
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fmycw8
|
What's the difference between OLED, AMOLED and Super AMOLED displays?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl6n4qc",
"fl7cqz5",
"fl8k2k9"
],
"text": [
"Short answer: It's complicated. OLED is display technology that involves the use of pixels made of organic material. AMOLED display technology combines the properties of OLED technology with a pixel-modulating matrix and thin-film transistors, essentially providing a transistor and capacitor to each pixel in the display. This makes AMOLED displays more expensive but also more flexible and energy efficient, able to provide more vivid picture quality and render faster motion response. Super AMOLED is a marketing term created by Samsung for an AMOLED display with an integrated digitizer. It is a more advanced version of AMOLED and it integrates touch-sensors and the actual screen in a single layer. Samsung claims it provides a 20% brighter screen, 20% lower power consumption and 80% less sunlight reflection. Edit: Added the information that Super AMOLED is marketing term.",
"Okay so think of it like this. > There's a class with few children in it. Here, each child is an OLED(Organic Light Emitting Diode) and the class is an OLED display. > All the children are given an activity to do. Maybe to draw their favourite animal. > Suppose there is a separate teacher for each child helping them draw, it's called \"Active Matrix\", the AM in AMOLED. > If there's a teacher for a group of students, it's \"Passive Matrix\" Super AMOLED is similar to AMOLED, just a bit more advanced. Hope this analogy helps.",
"My favorite simplification of OLED was in an article I read a few years back. It explained it as OLED being lab created fireflies, they turn on and off. Full HD tv's still have a glow when the screen is black but OLED's are true black, it looks like the tv shut off. I am not up to speed on AMOLED or Super AMOLED but usually these improvements just mean more color, brighter color, and more energy efficient. Hope this helps."
],
"score": [
1220,
215,
8
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fmzyo5
|
How do the graphics card, RAM, and processor all work together to determine performance of a PC?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl6w1tg",
"fl6y4ak"
],
"text": [
"CPU is its ability to do math. Everything a computer does is dictated by math, so this makes things faster. However you can't get faster than almost instant (dictated by speed of electrons wizzing around inside) so if the CPU is able to go at that speed, other things may slow it down instead. This is where we get to RAM. RAM (Random Access Memory) is the computers ability to remember things quickly. The CPU can't remember things on its down, so if you want it to, say, remember the keys you are typing in your keyboard, it needs RAM to hold that information until the CPU needs it. If the RAM is smaller than is needed, we get issues. On solution is to temporary store information on your hard drive, that that is orders of manitude slower, so your CPU has to twiddle it non-existent thumbs and sit around and wait for the numbers it needs to get to it so it can do more math. The Graphics card (GPU) is just another specialized CPU that has it's own RAM built in with it. 3D graphics involved LOT of very complicated math done very quickly. The GPU does that math so the CPU doesn't have to bother and it's custom build to do that specific math very well. If it's not good enough, you graphics will go behind. See the above two explanations for details, as either the GPU or it's dedicated RAM will be at issue. You're CPU can't handle it's own work and modern 3d graphics at once. Things that do not require 3d graphics do not use the GPU at all, usually. Crytocurrency happens to use similar math to 3d graphics, so that's why those are used for that. Hope that helps!",
"Think of a computer as a restaurant. The CPU is the head chef and sou chefs that manages all the tasks and sets up the menus. The faster or more experienced chefs will increase the performance but they are expensive. These chefs work harder and faster than any individual worker but they can't operate an entire restaurant by themselves. Most of the work goes to the line cooks which are the GPUs. While they are slower and less experienced, there are a lot more of them and they are cheaper to hire. They work in parallel to cook individual steps of a dish and put it together. If they are well trained and work faster, the restaurant can serve food faster. More of them can also increase sales if the restaurant can scale to allow more demand. RAM is the kitchen space. You need tables to hold ingredients for processing food. More dishes means more tables. GPU RAM is the stoves and cooking areas. Food from the tables (RAM) need to be transfered to these areas for specific processing by the line chefs (GPU). If your kitchen is too small, you will end up with \"too many cooks in the kitchen\" and end up slowing the entire process. Lastly, storage of food is the hard drive space. It takes some time to pull out the food and have it ready for the kitchen."
],
"score": [
20,
8
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fn2mqu
|
How do HD photos and videos seem to look better than our own naked eyes?
|
HD photos and videos seem to look better than the pictures formed by our own eyes. How is it so? I didn't know which flair would fit so I chose biology.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl77m17",
"fl7g57p"
],
"text": [
"The eye is really good at some things but not so good at others. Meanwhile, cameras can be good at what ours eyes are bad at, and that’s what really stands out. For instance, really high dynamic range. Seeing pitch black right next to bright white. In our eyes, this is weird because of the way light bounces and reflects. Plus our eyes are constantly adjusting to what we’re looking at. A camera can capture the highs and lows all at once without those adjustments. Then, when we see it as a reproduction instead of actual light, our eyes are able to see it in that static state. It’s not that it’s better, it’s just different from the way we normally see, and that makes it pleasant.",
"Genuine question: have you had your eyes tested recently? When I first got glasses it literally felt like the difference between standard definition and HD screens. You often don't really know what you're missing."
],
"score": [
101,
26
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
fn3o18
|
Why do archaeologists use "noninvasive imaging" technology to look around pre-Columbian temples rather than just walking in and having a look?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl7d6bq",
"fl8jsks"
],
"text": [
"You can tarnish some of the things in the temples by opening it. The reason these things still exist is because they were protected from the environment for so long, so if you open it up you risk causing everything to break down",
"Non-invasive imaging means even if you decide to excavate and open a chamber/temple/etc you have a better idea of what is located where, how to do the least amount of damage to the site, and the best way to start. (A lot of stuff gets broken in archaeology. Not always on purpose but it happens!). Also it can be more expensive to excavate and remove and then preserve objects. If you open it up, it gets exposed to a different environment. Changes in temperature and humidity can make things fall apart faster, and it costs money to prevent that from happening."
],
"score": [
34,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fn6lgb
|
How do spammers profit from spamming with bots,like chat invites?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl7u8p5",
"fl7u2kz"
],
"text": [
"If there is some underlying scam (e.g. Nigerian princes promising fortunes), probability suggests *someone*, *somewhere* will bite. Since the cost of mass-messaging is very low, it's not hard to imagine that if, say, one email/chat link out of a million results in you swindling someone, you can adjust the amount you try to steal appropriately such that the expected return on that single success is profitable. There are also some savvy strategies that exploit ad revenue mechanisms, especially in adult messaging spam -- take a bunch of photos that aren't yours, make fake websites using them, start fishing for people to chat with, direct them to the websites for \"premium access\" or something similar. Get enough traffic, use ad space, make some residual income. Or, more like the typical \"send me money\" scams, catfish someone and just keep sending them porn of some random person. And while you're at it, automate the whole thing with some programming.",
"It's not the invites themselves. They get alot of people in a chat and send ads for scams to them which makes them money."
],
"score": [
8,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fn9ei0
|
how do digital devices (like phones, computers) keep time? I get clockwork but even my fairy lights have a timer on - how?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl8aaf3",
"fl8c4ab"
],
"text": [
"Clock chips are cheap and the feature might increase fairy-light sales.",
"The simple way to have an accurate close in an electrical unit is with a crystal oscillator. It is a physical crystal that is shaped so it vibrates at a specific frequency just like how a tuning fork vibrates a specific frequency. Some of them are [fork-shaped]( URL_0 ) and for clocks, they are tuned to 32768 Hz. They can be used to create an electrical signal with just that frequency and you then have a circuit that counts the pulses to measure time. after you count 32768 pulses a second have passed. There is a reason that you have mechanical clocks and quartz clock. When in operation you have a crystal with a higher frequency that produces the color signal that the device uses internally. But when turned off you have a small battery, crystal, and part of a chip just to run the clock all the time. Any net-connected device can use a standard protocol to connect to a time server to get the exact time so your phone and computer will get and update the time multiple times per day if you leave the function enabled."
],
"score": [
5,
3
],
"text_urls": [
[],
[
"https://en.wikipedia.org/wiki/Tuning_fork#/media/File:Inside_QuartzCrystal-Tuningfork.jpg"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
fn9ybx
|
Video Games Objects & Backgrounds
|
ELI5: In video games -my most specific case being a racing game, is the Racecar an object in motion meaning is it moving through a large environment (map) or is the Racecar stationary and the map moves around it?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl8dq17",
"fl8e4vu"
],
"text": [
"Either is possible, but it's usually the car moving. The map-movement variant is more common in 2D",
"Usually the race car is an object moving through the environment. There are all kinds of reasons why, but to put it simply, it’s just less work for the computer in most cases. There’s less computation involved in moving one race car based on simulated, abstracted physics processes than in figuring or how everything else would move around to make it look like the car was acting under those processes Edit: a static environment also just makes it easier to have multiple moving objects. Additionally, there’s rarely just one solution to a given programming problem, so while what I described might be normal, there could be some game where the creators had a good reason to do things differently"
],
"score": [
10,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
fndlw7
|
How computers work using only 1s and 0s?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl911li",
"fl9357n",
"fl908sg",
"fl93i9i"
],
"text": [
"First of all, think of computers as having the purpose of displaying the correct image on screen, printing your document correctly, responding to keyboard and mouse presses correctly, and, in general, controlling other devices (speakers, VR goggles, whatever) so that YOU can interact with them. All of it is for your benefit. So how does a screen work? Well, every dot of color that lights up to form your image, is controlled by a memory bit. If the memory is 1 (i.e. 5 volts in it), then the pixel of color lights up (5 volts in the pixel too). If the memory is 0, then the pixel is off (0 volts in it). Your screen has a memory chip that matches the number of pixels, and whatever's configured in that memory is displayed with the pixels. So the computer's processor and video card have the capability to flip 1's and 0's around, switching memory bits from 5v to 0v and back, millions of them very fast. Software just instructs the processor which memory bits to make 1 and 0, based on what you're doing (typing, drawing, playing games, etc.). The whole computer is a big math machine designed to work with 1's and 0's (5 volts and 0 volts) so that the attached devices show you the correct patterns of light and sound, which your brain then interprets as a game or a word processor software.",
"When it comes to doing math, computers use what's called a different [radix]( URL_1 ) or base, which is a different system of notation. We're used to using the decimal radix (deci being a prefix meaning ten), having 10 digits (0-9) and with 10 meaning ten. Raising that exponentially one power gives you 100 or one hundred. But there are other radixes, like: * octal, with only the digits 0-7, where 10 means eight and 100 means sixty-four * hexadecimal with the digits 0-F, where 10 means sixteen and 100 means two hundred and fifty six * and, used at the low level within computers, binary which has only the digits 0-1 where 10 means two and 100 means four The thing is, math still works in other radixes, only the notation is different. For computers, binary is especially useful because each digit position can be represented with a simple on-off switch/light as either a 0 or a 1. That representation is the easiest and simplest for an electronic device to work with. But there's a bit more - binary also allows for using [boolean logic]( URL_0 ) to easily express logical concepts like AND, OR, and NOT at the same simple fundamental level. So it's really easy for the computer to work with things as a bunch of tiny switches, and then at the end, when we want output, that series of 1s and 0s can be interpreted as characters that make up decimal digits of a number, letters, a color, or sound, duration to rumble a joystick, or whatever.",
"Binary is as simple as 1’s being “on” and 0’s being “off”. Computers essentially run off instructions that depend on binary. I suggest googling and going from there.",
"Ones and zeros are combined to count numbers. It's best shown as an example: * 1 = 1 * 10 = 2 * 11 = 3 * 100 = 4 * etc A computer uses one number to describe the operation (e.g., add = 1, subtract = 2, etc.), and then two other numbers for the operands of the operation. The computer has memory and a fourth number is used to tell the computer which memory address gets the result. When you tell a computer what to do, you feed it these four numbers, all in binary. This group of four numbers (operation, operand, operand, result) is called an 'instruction'. A program is made up of a series of these instructions. It is, of course, a little more complicated than this but these are the basics."
],
"score": [
11,
11,
5,
5
],
"text_urls": [
[],
[
"https://en.wikipedia.org/wiki/Boolean_algebra",
"https://en.wikipedia.org/wiki/Radix"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fnhvqt
|
How do ventilators help people breathe and are they complicated to manufacture?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fl9m0dl"
],
"text": [
"They work by forcing air in and out of the lungs. Ventilation can be made using a machine or manually using a bag-valve-mask (BVM) device. The main idea is to keep a good flow of air in and out and to ensure that a sufficient amount of the lungs is actually in use to allow the transfer of oxygen and carbon dioxide between to and from the blood. The machines are simple in that all they have to do is pump air in and pump air out. The complex part is making sure that the lungs are not overinflated, not stressed and sufficient air/oxygen/carbon dioxide is supplied and exchanged. There are other factors as well but these are the main points. As an example of a complicating factor, the rate at which air enters and leaves the lungs is not just constant in, then constant out, but follows a quite complex curve - not sure if you've seen the respiration flow traces on one of the monitors. There are a number of mode of operation of these devices to assist not just in the flow of gasses but also to ensure that the speed of gas flow is correct, that \"resting\" periods take place and so on. In fact the air flow into the lungs is extremely complicated. A very simple device but with many components to make it safer and more effective to use - this is what makes them complicated. Then there's all sorts of interesting issues regarding medical compliance, testing, certification and so on. Hope this helps. & #x200B; Edit: received my first gold - thank you kind anonymous redditor!"
],
"score": [
16
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fnrx0e
|
If RF radiation is really safe why people that operate big antennas tell otherwise?
|
Over the years I met several big antenna operators (mostly TV broadcast repeaters and mobile networks combined) that told me how they don't like to be near them longer than necessary due to enormous power, frequent headaches, dizziness and possibly carcinogenic properties. Now, what I read on reputable sources, RF as non-ionising radiation should be safe, always. Yet, not only people that operate those big antennas are very cautious, but on the internet as well, here and there I can find how both mobiles and wifi's are still young technologies to be thoroughly evaluated and examined and how brain tumors can be linked to long RF exposures.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flb59j5",
"flb6t0s",
"flbagjv"
],
"text": [
"Big antennas can be dangerous in some parts of the spectrum because they operate at insanely high power levels. High energy RF/microwave transmitters can cause heating and induce voltages in metallic objects. They're also just generally dangerous industrial workplaces due to their height, remote locations, and high voltage power. Mobile/WiFi transmitters operate on a tiny fraction of the power of a big transmission tower, and are an extremely well studied field healthwise.",
"RF is not \"always safe\". RF is only dangerous in the electric currents it generates within your body. This is in sharp contrast to ionizing radiation. Nobody's scared to touch batteries because, despite generating small electric currents in our bodies, we know that these currents are small enough to do nothing. The same goes for low-power RF. Your phone, for instance, uses very little RF. A many-watt or even kilowatt antenna is stark contrast to that. It's the difference between touching a AA battery and touching an industrial powerline.",
"ILE5: A candle is not hot from 30cm away, but it is if you put your finger right next to the flame. Full answer: there is a spectral component to RF signals. Certain materials absorb certain frequencies. Which isn't always bad if it's a weak signal. Like water absorbs for instance at 2.4 GHz, that's how your microwave works (500-1000watts) but your Bluetooth at 2.4Ghz will not warm that same cup of water with it's few milliwatts."
],
"score": [
37,
9,
6
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
fnst8p
|
If both people are on speakerphone during a video/phone call, how does the technology prevent each person from hearing their own voice being broadcasted from the other person's device?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flbeb6m"
],
"text": [
"it's called *echo cancellation* and one such method is to employ cross-correlation filtering. This is where you take two (or more) streams of audio and apply a correlation filter (basically seeing where they match) and subtracting out what is filtered (e.g. subtract out the echo coming back)."
],
"score": [
17
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fnznkp
|
How do hospitals store patient data?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flcfyaz"
],
"text": [
"Any major server system that requires storage will use dedicated data storage devices. The data storage system will almost certainly have built in duplication, backup and data integrity checking systems typically across multiple devices to provide redundancy against hardware failures, power failure etc etc. On top of that, it is also now very likely that data can be hosted on cloud platforms (AWS, etc) These are dedicated server farms with all the protections plus more. (It is likely the data will be safe even if the hospital is destroyed in an accident or fire) These are not either or options. A large firm might have local data as their primary storage and use offsite cloud services for backup. The system is pretty extensive and complex and they try to mitigate against the more obvious failure modes."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fo264p
|
how was the footage of the first moon landing (Armstrong emerging from the capsule) captured? Was the camera attached to another module or did he place the camera down first, go back into the capsule then come back out again making it, technically, the 2nd moonwalk?!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flcqlvm",
"flcwbub"
],
"text": [
"The lunar lander had a module in which they could store equipment for easy access from the surface, which had a camera facing the ladder installed in it. [This is how it looked]( URL_1 ). Edit: [Better image from the wiki page]( URL_0 )",
"When he exited the LM, he pulled a cable attached to a nearby equipment hatch. This released the camera and turned it on. I believe if you listen to the full audio you can hear Houston confirm the camera is working before he continues down the ladder."
],
"score": [
18,
5
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Apollo_TV_camera#/media/File:ApolloTVCameraOnLunarModule.jpg",
"https://i.stack.imgur.com/n7if4.jpg"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fo4hr4
|
Why is audio quality always bad when you call someone, but over Skype or Discord it can sound really good, even if they are calling with their phone?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fld1gmw",
"fld3g7e"
],
"text": [
"I am not sure about this, but i reckon it is because Skype/Discord uses your WiFi or ethernet which has more bandwidth.",
"Imagine people spoke in light instead of sound. And imagine that human \"voices\" did not come in every visible color but only in the range of the spectrum that included yellow, green, and blue. That would allow makers of light \"phones\" to save a lot of money and effort by just making phone lines that could clearly transmit yellow, green, and blue. Speech would sound pretty clear, but the overall light \"picture\" wouldn't exactly look very natural, with red+orange and indigo+violet pretty much completely missing. Actual phones do this with sound. They don't carry all audible sound but just the frequency range that's essential for human speech to sound clear (300 to 3400 Hz). Skype and Discord, on the other hand, give you more or less the full range."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fo78qv
|
How come my budget LG TV with weak CPU can run huge 4k HDR video files?
|
I don’t get it. My TV has very weak CPU, even the user interface navigation is slow. However it runs 40GB+ Blu-ray rips from HDD with no problems. But when I play the same file on my PC connected to the same TV, it takes like half of my GPU (GTX 1650s) processing power, which is insane.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fldle3r",
"fldi36y"
],
"text": [
"It's the difference between a processor and a decoder. Your TV has a pretty easy job. The video signal being fed to it is encoded using what's called a *codec*. The TV's only job is to run that encoded signal through a decoding process, then send the decoded patterns to the display for you to see. It's a fast process and doesn't require much \"thought\" on the part of the hardware because all of the hard work is already done. The TV doesn't need to worry about how the picture is supposed to look because that data is already encoded and ready for use. Basically, your TV is just reading a book. One page, one frame. It's easy work. Your PC, however, has to do a lot of work every second you're playing a game. The GPU needs to figure out what you can see in the game world, how the lighting sources in that world are affecting those objects, their scale and movement relative to you as you move about in the game world, and a whole lot of other factors - all to make the picture look right. It's a lot of very intense math work, and it has to be done extremely quickly, otherwise you see framerate drops and other problems. Unlike your TV, your PC has no book to read - it has to write that book on the fly. In order to give you that glass-smooth visual performance, it has to write up to 60 pages per second or more and have them ready for your viewing enjoyment. So why doesn't the TV have to work as hard? It comes down to optimization. Your TV is a highly optimized piece of equipment. All it's designed to do is run codec-processed video through its decoder and put the images together for you on screen. That's all it's designed to do, so everything about its hardware is designed to make that throughput as simple and easy as possible. If you were to hand it anything else, such as unprocessed video data, it wouldn't know what to do with it. So, while it's a wonder at codec-processed video, it's unable to do anything else. Your PC, on the other hand, can do much more, but that means it's not optimized for lesser tasks.",
"It has a dedicated processor for the codecs that are commonly used for broadcast and storage of movies. That decoder chip isn't good at much else, so it is relatively cheap compared to a general purpose processor or GPU that is much more flexible."
],
"score": [
14,
13
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
fo7wha
|
How do military planes and drones (made to target ground units, houses, and so on) see through things like clouds and heavy rain?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fldlzuq",
"flds5ri"
],
"text": [
"The best answer is that they don't \"see\" through clouds and rain. If the targeting system is purely visual (it rarely, if ever, is purely visual, but say it was) they couldn't target anything they couldn't see. In reality, they use combinations of targeting systems. There are visual targeting systems, sure, but there are also radar, infrared, and I'm sure other types of targeting systems. The planes can fly through all kinds of stuff that they can't see through, because there's not a whole lot of things to hit in the sky, and they have radar and other sensors to find objects that are close to them, so they don't hit them. They also have 3d maps of the earth to make sure they don't hit mountains or other land obstacles.",
"People can only see visible light, which is blocked/scattered by clouds and rain. Some kinds of light like UV, infrared, and radio (radar) can see right through a lot of that stuff. They are also being guided by satellites and other methods of communication and stored memory of where things are. As long as it can \"check in\" to guidance systems every so often (and supplemented by visual methods) it can remain on course."
],
"score": [
12,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fodnsy
|
How is the audio quality of a phone measured?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flekotc",
"flepwvm"
],
"text": [
"They can measure how it responds to different frequencies, you make it produce a specific pitch and measure with an instrument how loud each frequent comes through, usually you want every frequency to be as close in volume to the others as possible",
"You play a set of tones, the record those with a microphone or through a jack depending on what you want to measure, the replication or the speaker. When you tell the driver (speaker) to play set tone at set volume, you can measure that from the signal or with a microphone. You then compare that to a reference chart of desired results. You want different kinds of sound profiles for different uses, for media you want as accurate and broad as you can. For speech you want to limit the range to only speaking frequencies to make sure it can be heard as clearly as possible."
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fogbbr
|
Why don’t modern electric vehicles use transmissions?
|
I understand that modern electric motors have such a wide powerband that they don’t need transmissions, but why didn’t they go with the option of building smaller/less powerful motors and pairing them with transmissions? Is it just more cost effective to have bigger motors/batteries than to build a smaller motor and tranny for it? Less failure points for warranty control? Too much low end torque for a cost effective tranny to handle?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flf0kll",
"flf0lz7",
"flf2708"
],
"text": [
"If you can remove points of failure,reduce maintenance of the vehicle, then that’s what you do. Why build in more points of failure into an inferior design? No reason to stick to it just because it’s familiar.",
"Any part you add to the drivetrain adds friction and reduces your efficiency. It also adds weight to the car which reduces your gas mileage and the increase in complexity means more maintenance cost. Also, a specific gear in a transmission has a specific point of best efficiency. If you aren't at that specific speed you aren't operating at your peak efficiency. CVTs (continuously variable transmission) exist to get around that. Basically, electric motors can be properly selected to operate across the entire operating range at a higher efficiency than any transmission you can design so there really just isnt a point in doing it. Edit: electric motors are also very easy to make at the right power band and they aren't much cheaper if you go a bit smaller so there isn't any real savings there either",
"Transmission are needed in ICe engines because they don't provide power levels at wide range of rpms. ICE provides 0 power at 0 rpm, very minimal at idle 600rpms. So that's why you need a transmission. Electric motors DO provide alot torque at 0rpms, basically 90% of max. And they can maintain that torque thru out the entire rpm range. So there's no need for a transmission to lower your rpms down"
],
"score": [
13,
7,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
foioxy
|
What is bandwidth and how do you get more of it?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flfe7ca"
],
"text": [
"Think of a hose. Bandwidth is the size the the internet hose. Bigger hose allows more internet to flow. Bandwidth is limited artificially by providers, and physically by things like the actual limitations of how much data a cable can transfer. Normally it would be a switch but with most people working from home at this point it's likely that the hose is just too small for the number of users."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fooatt
|
How-come graphics in video games aren’t as good as most cgi in movies?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flg7ifh"
],
"text": [
"Graphics in videogames have to be rendered in real time, 30-60 frames every second, on a single computer. Movie CGI can be rendered with thousands of computers over a very long time. Each computer can spend days rendering a single frame."
],
"score": [
33
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
foshz4
|
When agreeing to cookies on a website, what exactly am I agreeing to?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flhqy0y",
"flgy35c",
"flh91tm",
"flgxe7x",
"flhifiz",
"flh5q8c",
"flin877",
"flhm1od",
"fli85er",
"flhoqwc",
"flifajj",
"flhxj36",
"flk3l4d",
"flh9yl9"
],
"text": [
"Its like getting your hand stamped when going to a fun park with food. You have to buy a ticket, but after you do, they stamp you so they know you've been inside the park. If you wash off the stamp, they'll have to see your ticket again, but with a stamp, you can just show them your hand and be back to riding fun rides super quick. In fact, you can leave the park and come back, show them the stamp, and they'll let you in right away! edit: please note that this is very simplified. read some of the discussions to get a better grasp of why they do this in the first place, how this can violate privacy, and why that can be a problem.",
"First a definition: A cookie is a short piece of data - less than 100 bytes typically - that the server assigned to the browser. Then for each page loaded from the same web site the browsers sends that same cookie value back to the server as a way for the server to say \"this is the same browser/person as last time\". This will usually persist as you turn your computer off/on, change internet providers, or just roam between Wifi and cellular in the case of phones. It's essential for web pages where you can log in with an account so that you stay associated with your account, but any web site can do it for any reason. Some web sites let you have preferences without an account - these are stored in the cookie in some way. Other web sites just give everyone a unique number in a cookie and let the analytics bot have its way with them. Since this constitutes user tracking there are privacy laws that get involved and this is the disclaimer. It's really picked up since the European GDPR law came into effect.",
"You agree to let them put tiny files on your computer that they can later read again. Normally when your computer talks to a website each new page you open is like the computer talks to the website for the first time. Imagine having a conversation with a complete amnesiac. Every time you introduce yourself and start talking to them they immediately forget what you just said and you either have to start over again or live with the fact that amnesiac you are talking to has no idea who you are or what you have been talking with them about. This sort of works for the sort of stuff the web originally was designed for: Static stuff that is completely anonymous and without context. It works less well for modern websites where you want to adjust what they show you based on who you are and remember what you have done before and even do stuff like e-commerce in a non stupid way. You could preface each sentence you say to the amnesiac with your name and where you last where in the conversation, but that gets cumbersome really fast, requires you to remember stuff that ideally the other side should remember and has big security flaw in allowing somebody else to imitate you and pretend they are you. Cookies are a way to work around the amnesia. It is like the web-server guy handing you a name badge when you first start talking and asks you to put it on. the badge may contain your name and an identifiable number and some other info, so every time you start talking to the amnesia they look at the badge as you talk to them and immediately remember who you are and may even be able to look up what you said before. It makes things easier. Of course there are potential threats too. Some people may enjoy their anonymity and having a complete stranger slap a name-tag on you as you walk by to track who you are seems rude. This is why the EU mandate that websites should at least ask people first before they put a tag on them and not just do it without asking first. A website like reddit needs to use cookies to tag their users and tell them apart, but other websites that you don't really want to remember who you are and build a profile of you and what parts of their website interest you have less of an excuse. It is balance between being useful to make websites easier and more secure to use and simply tagging users like wildlife to track them and study their behavior. You may want one but not the other. Ideally only the websites that put a tag on you can see that tag. So URL_0 does not know what tag URL_1 has given you, but in practice people have found ways around that. Especially advertisers with their ads on all sorts of sites you visit have an interest in figuring out all sorts of personal stuff about you that you might not want them to know. In a perfect world we would only let websites put cookies into out browsers when it is necessary to make the site work, but too many websites claim that they need it to work when they really don't in order to invade your privacy. Even worse big advertisers have found ways around the whole needing a cookie to track you think. Normally a webserver is not just amnesic, but also completely faceblind. To prosopagnosic amnesiac everyone looks alike and without the cookies they should have no way to figure out who is who. However they do notice certain things about the person they are talking to, like what webbrowser they are using and stuff like that and based of that they might be able to built a profile of everyone they talk to tell people apart without needing cookies. This is bad if you care about privacy and don't want google to know what weird shit you are into and sell that info to the highest bidder.",
"You are agreeing to have special files installed on your computer that will store certain information for the website to access. For example, a cookie file might store your account information when you check the 'remember me' box while logging into your account.",
"From a technical perspective (not a legal one): It really bugs me that websites feel the need to put these warnings up. Your browser is something *you* control. The web server is something that someone else controls. You are a customer going to a place. The place is giving you a loyalty card because they aren’t going to remember for you. It’s on you (and your browser) to keep and return (or not) that loyalty card. So if you really care about privacy, tell your browser to not store or give back loyalty cards. Don’t trust them to tell you “don’t worry, we won’t give you a loyalty card, or use any you happen to give to us”. However, you’re going to have a hard time using websites normally if you disable cookies entirely. Most websites require them, at least within a single “visit”, to work properly. Fortunately all browsers these days have a common option: “clear cookies on exit”",
"Can someone please remind me of how some people recommend to deal with these? Like an extension to Accept all automatically then delete cookies upon exit or something. Been meaning to do this, get sick of clicking Accept all the time.",
"There's a lot of wrong or at the very least uninformed answers in here. ## Most sites that use popups don't understand why they do The first thing to know is that this cookie popup is overused for reasons that the people who run these sites don't care to understand. Nearly every site uses cookies or something like them, but *only those that use such tech to track your actions outside of the requirements of the site must have a popup.* For example, if you have a website that lets you login to see private stuff, or update your profile etc. *you don't need a popup*. Have a site with a shopping cart? *No popup needed*. The directive only applies when type using cookies in a way that's not a basic functionality of the site. Say for example if you're using cookies to track people's movements on the site for your own records, or if you're traking people across different sites *(coughfacebookcough)*. ## It's not a cookie law The ePrivacy Directive does not refer to cookies directly. The directive was written to intentionally avoid tying the spirit of the law to the technology of the time. It applies to things like LocalStorage, Flash cookies, etc. as well. You need to acquire consent to track user behaviour if that tracking isn't an obvious requirement for using the site (like a shopping cart). ## Not GDPR I know that for non-Europeans, you're only going to hear about the occasional Big Thing that comes out of the EU, but you should resist the temptation to bundle everything under one headline just because it's what you've heard... especially when it's pretty obvious that these cookie popups started appearing *years* before GDPR was even mentioned. These popups are the (misinformed) reaction to the [ePrivacy Directive]( URL_1 ), a move by the EU to try to force websites that are collecting data on people to disclose that fact. [The General Data Protection Regulation]( URL_0 ) is a separate set of rules that apply to your rights as an EU citizen in dealing with tech companies. Among other things, it: * Requires that a company can't store stuff about you that it doesn't need to perform the services you asked them to do for you (via informed consent). * Prohibits the sharing of any personally identifying information with third parties without informed consent. * Requires that the company make available to you everything they have on you, and delete all of it from their system at your request. They're totally different things. ## So what are you agreeing to? Well, *did you read it?* 'Cause of you didn't read it, you could be agreeing too anything. More often than not though, it's some legal boilerplate acknowledging that the site uses cookies and that they'll use that data for whatever they want. The CEO probably heard this was what her friend was doing on their site, so she ordered her web nerd to do the same and stopped thinking about it.",
"For the curious, on Chrome you can see cookies by: 1. Right-mouse click > Inspect 2. Application Tab 3. Expand the cookies option on the left side menu 4. Click into any of them to see what's being stored",
"They want to put these baked goods inside your computer. Except these baked goods actually contain pieces of information. And some bad people will want to see and eat your cookies.",
"It's like when you meet a neighbour for the first time in a new neighborhood and they give you a name tag so they'll remember who you are next time, and other people on that street will also know who you are and what your name is.",
"Follow up question that I didn't see asked. What happens if you don't click 'ok' but you continue to use the website? Are cookies only stored after clicking 'ok' or are they storing cookies by default and the pop-up is just a requirement to let you know?",
"You're agreeing to let the website put a tiny little text file on your computer (or phone). Websites will then read this little text file to learn stuff about you. Some will use it to save you time, by \"remembering\" your login and password which they read from the text file. Many will read *all* the text files left by different sites you visited. That lets them figure out where you've been online, what you like, and what kind of advertising to show you.",
"Cookies are often used to track your preferences when you visit a site. Examples: What sections you visited, types of products you looked at, what default settings you prefer, etc. so that next time you visit the site it can load those preferences for you automatically. Also, other sites can also look at your cookies and set their preferences accordingly. Which is why when you do a Google search for cowboy boots, you suddenly see ads for cowboy boots everywhere you go on the web. Besides this being somewhat annoying for some, cookies can also be dangerous for others, e.g. a woman in an abusive relationship who may have secretly been looking for a women's shelter could inadvertently give away that fact to her abuser.",
"\"Can we put a badge on you with a number that will identify you, so that when you come back to this - or a related - website, we can tell who you were and when you last came to that website, etc.?\" They know that badge number 2389473 visited them on Tues, Fri, went to this page, that page, clicked here, bought this item, came from this Google search, etc. but they don't know \\*everything\\*, only what you've given them (what you did while you were wearing the badge). Clearing cookies is removing all the badges from yourself. You'll get new ones instead, so they \"shouldn't\" be able to link back to whatever number you had before. But you will likely \"log in\" to a lot of websites, so they will know that your website account was also associated with badge 2389473 and is now being logged into by badge 967493748 too. It's a harmless number, on its own, but it provides a lot of links to what you do on them and their sister websites - but bear in mind that you're ALREADY DOING THOSE THINGS ON THOSE WEBSITES, they know you are, because it's their website! So it's not really all as drastic as people make out. It just means they can join together a lot of information that would otherwise look like separate website visitors, knowing that it was all \"you\"."
],
"score": [
10011,
2802,
217,
94,
18,
12,
6,
5,
4,
4,
3,
3,
3,
3
],
"text_urls": [
[],
[],
[
"CNN.com",
"Reddit.com"
],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/General_Data_Protection_Regulation",
"https://en.wikipedia.org/wiki/Privacy_and_Electronic_Communications_Directive_2002"
],
[],
[],
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fossrl
|
How does Morse code work
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flgy9k0",
"flh038m",
"flh7r5j"
],
"text": [
"With silences. A silence the duration of three dots separates between letters, while a silence with the duration of 7 dots separates between words.",
"Morse code comes from a time when we couldn't transmit voice or video over wired and wireless links yet. Imagine having a radio where the only reliable sound you can make is a beep. So we invented a method of using different beeps to represent a message. Morse consists of 3 symbols. A dot or short beep A dash or a long beep And a space or silence Each letter and number is encoded using a series of these symbols separated by a space to represent the end of a word. Interestingly a lot of abbreviations we still use comes from Morse. Like MSG for Message, or OK for okay. This was to make it easier to transmit messages. So technically we've been using internet slang since the Morse days. The most famous one of course being SOS (Save our Souls) which was used because SOS in Morse is ... - - - ... which was very easier to transmit and very noticeable. If you've studied aviation at all you would know that all airports have a 3-digit designation like YYZ (Toronto) which also comes from the Morse days When you get good at it people can listen to morse and translate it live. This is a live translator that you can input words and sentences and see what the output would sound like in Morse. You can hear the spaces. URL_0",
"Letters, words, and sentences were separated by increasing amounts of silence. Also, telegraph operators would typically write the letters down as they arrived, and if something was unclear you could figure it out by context."
],
"score": [
10,
4,
3
],
"text_urls": [
[],
[
"https://morsecode.world/international/translator.html"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fot8aj
|
What is a checksum and how does it work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flhih9o"
],
"text": [
"You can try checksums yourself with a credit card number: URL_0 Double every other number starting with the 2nd then add all of the resulting digits (so 12 would be 1+2). The result will be a multiple of 10. Always. If you miss or swap a digit, the checksum is off (not a multiple of 10). That allows web pages to detect typos immediately, rather than spend time (and money) looking it up in the credit card network."
],
"score": [
6
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Luhn_algorithm"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
fotql0
|
Why do numbers on phones start on the top left, when almost everything else starts on the bottom left?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flhcbij"
],
"text": [
"Numberphile did a [video]( URL_0 ) on this very question a while back. The short answer is that when phone companies were moving from rotary to push button phones, they came up with a bunch of different possible layouts, the calculator layout included, and asked people which ones they like best. Watch the video though, it's great. Some of the alternative layouts that they considered are crazy to think about."
],
"score": [
3
],
"text_urls": [
[
"https://www.youtube.com/watch?v=kCSzjExvbTQ"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
fowy37
|
What is end to end encryption and why is the government trying to ban it?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flhoko6",
"flhr77a",
"flho83d"
],
"text": [
"you and your friend have a safe with a lock and only you and him know the code. You put a message in that safe and mail the safe to your friend. That message is protected and cannot be seen by anyone handling the safe except your friend when it arrives to him. So the message is encrypted on your end, or put in the safe box and then sent to the other end where your friend is, and also where it is encrypted or locked in the safe until your friend opens the safe. But you can just break the safe right? So you encrypt the message further, you tear it up into a hundred pieces and send it to your friend. But before this, you gave him a blueprint of how to put the message back together. This is end to end encryption. Only either end can decrypt the message to see it. I don't know about the government part. But I might have a few guesses.",
"The reason some governments want to ban end to end encryption is because it makes spying on their subjects harder. Officially, the talking piece is that the government needs to know what everyone is doing and saying online because it helps catch terrorists. End to end encryption is really hard for the government to read though, so they want to try and ban it so that they can read everyone's communications more easily.",
"End to end encryption is when the communication is encrypted between the endpoints. If you think of reddit, there is encryption from you to reddit and from reddit to me, but anyone with access to reddit can read what you write. If you encrypted something to me, and then posted it on reddit, and after I downloaded it I could decrypt it. This would be end-to-end encrypted. Sure, someone could go to reddit with money or a court order and get the data, but it would be encrypted so they couldn't read it. This sort of thing cannot be banned. Governments can complain, and it can be made harder, but that's all. FJKEH GIOEW XSPED FKWSX DQAJK RCODM NDOWS"
],
"score": [
30,
11,
6
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fozt23
|
How does my watch use a flashing green light to measure my heart rate?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fli6wmq"
],
"text": [
"According to Apple, the Watch uses a technology called photoplethysmography, or PPG, to measure heart rate. It’s essentially testing how much red or green light it can see when looking at the skin on your wrist. Blood is red because it reflects red light and absorbs green light, so when your heart beats, there’s more blood flow in your wrist, and more green light absorption. Between heart beats, there’s less absorption of green light."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fp0qn1
|
Why do countries have diffrent types of plugs?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flicha2",
"flidkd8"
],
"text": [
"In our global age, we forget that 120 years ago people didn't fly around the world. People didn't fly or even travel very much at all. Each country did its own thing, and when electricity came along, each country said \"we need a standard plug for everything!\" But because nobody traveled much, and countries didn't even get along that well, each country came up with its own standard. Heck, even the electricity that comes out of the plug is not the same everywhere. The voltage can be different and the frequency also varies. When I was transferred to Germany, I had to buy a transformer to run my American electrical appliances, which wasn't cheap. But if I had managed to plug my US toaster straight into the German socket, the toaster would have been fried. It would be great if everyone could agree on a standard everywhere, but there is simply too much equipment out there to just change everything, so we deal with all the different plugs and voltages that started 120 years ago.",
"When electricity was first introduced to homes in 1882, people didn’t tend to travel abroad very much. The first commercial flight didn’t happen until around 1914! So people needed plugs to make their lights work, but they certainly weren’t bothered about whether or not their plugs were the same as plugs in their neighbours house, let alone in houses in another country. They were just pleased it worked, and (mostly) safely. As time passed, people did start to think “hey, it sure would be good if we could all agree on one plug design and all use the same - that would help manufacturing and trade of electricals internationally”. Unfortunately, it wasn’t much later that world war 2 started, and people ended up with more important things to worry about. After the war, there was further talk about standardising plugs later in, but the enthusiasm had died down by this point. Nowadays it would be a nightmare to replace all the plugs in a county with standard ones - much easier to just ask everyone to buy adapters instead!"
],
"score": [
10,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fpai52
|
how and where do companies like Google store this insane amount of data?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fljsbv3"
],
"text": [
"Datacentres with vast arrays of computers filled up with high-end hard drives. Google got tired of using off the shelf computers so they designed their own server computers tailored exactly to what they need. URL_0"
],
"score": [
13
],
"text_urls": [
[
"https://www.google.com/about/datacenters/"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
fpd2vl
|
Why does Skype never close?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flk7t0m"
],
"text": [
"Skype allows you to accept incoming phone calls and in order to do so must be running on your computer. Having the program running is like having a smart phone turned on. Your smart phone works similarly but doesn't use a separate program so it isn't as obvious. If it blocks shutting down while you are not using it that is likely a bug and not intended functionality."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fpdqot
|
How a Website detects specific devices accessing it?
|
Hi, The question says it all. For example, I can’t do specific things if I use more than 5 accounts of AliExpress on a single device. Now my question is How AliExpress detects the exact devices. The restrictions always applied no matter if I use browser or the app.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flkgybs"
],
"text": [
"When your browser contacts a web site asking for a web page, it sends a header with more than just the request. The header is full of information like \"this is browser X, version Y\" and \"I'm on a machine running Windows version Z\" and \"I understand the following protocols\" and \"I have the following plugins installed:\" and \"I like this character set\" and \"My preferred language is ...\" and so on and so forth. Oh, and most importantly, it includes a header line that says \"These are all the cookies I was supposed to give you.\" Your browser sends so *much* information that it's like a fingerprint. Some web sites can identify individual users from this fingerprint. It's like they hardly even need cookies. And *with* cookies, the web site knows exactly who you are and every one of their trading partners you visited and what you did there. That's why you can e.g. casually mention diesel generators on a Facebook post, and for the rest of the month you'll see ads for diesel generators everywhere you go. (And for the record, I don't think I've ever typed \"diesel generators\" on the internet. It will be interesting to see who starts advertising diesel generators to me. Diesel generators. Diesel generators.)"
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fpfypi
|
How do laser thermometers work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flkqzbf",
"flkp0o5"
],
"text": [
"the laser doesn't do anything. it's just a visual aiming device. the measurement is done by an infrared sensor. warm/hot things give off infrared radiation, which the sensor detects. more infrared = hotter object",
"They have a narrow beam infrared temperature sensor. This measures the temperature by detecting the heat photons generated at the surface. The \"laser\" is just so you can see where the temperature sensor is pointed."
],
"score": [
9,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fphm48
|
How does a busted hard drive that won’t boot anymore get its data recovered when you take it to the magic computer repair shop?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flkyqww",
"flkyy4l",
"fll537g",
"flkzu4q"
],
"text": [
"There are some tricks to it. If you only lost your MBR, the drive can be dropped into another machine and the data recovered. If the drive is truly dead, as in it does not spin, it can be sent into a shop that will remove the platters and place them into an identical drive and then recover the data. That method is expensive and takes a while.",
"Hard Disk Drives (HDD for short) save data by magnetically marking a thin film if ferromagnetic material. So if the disk doesnt want to boot they bring it to a magic machine that can read all the lil magnetic marks.",
"To explain a little bit more basically, a hard drive is like a book, you first have an INDEX of contents, each file, what page it's at (on the hard drive it's more like GPS coordinates for each file), and then you have a whole bunch of files one after the other. A lot of times, when the computer doesn't boot anymore, it's because the INDEX is screwed up, so the computer doesn't know where the files are. You can use another machine or \"magic software\" to just read the files, and the software reads the hard drive and tries to figure out where each file starts, and where it ends. Most files have bits at the top and the bottom that identify it, so the \"magic software\" is often able to recognize word documents, jpeg pictures, music files, etc.",
"Depends on what you need to do, a few things are available, in increasing technical difficulty: 1. Run an unerase program, ignore the filesystem program, read the whole drive, and piece together the stuff you could read. 2. Replace the main board on the drive with an identical one. If it was an electronics failure this is fairly straightforward and doesn't require a clean room, but it's vitally important that you have an identical board. 3. Pull the platters out and put them in an identical drive, not only must the drive be identical, but you need a clean room, and there may be complicated procedures to do this. This may include cleaning the platters too. 4. Replace the firmware with firmware that returns the actual read data, and post process this to your data. This can recover a zero'd drive and bypass checksum failures. You generally need to partner with the hard drive manufacturers and pay them to write this special software for the drive you have. Often will be combined with \\#3"
],
"score": [
31,
9,
7,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fpifrd
|
The technology/algorithms behind aim-botting in an FPS.
|
So I get that someone can cause their character to aim at another character but the question is more along the lines of how it works? Is it an X,Y axis on the user’s screen and the aim bot detects the enemy on that plain and just moves the user’s cursor to that X,Y coordinate? Or is it more along the lines of detecting where on the map the player is through the games code? I have no background in coding I was just always genuinely curious what math / calculations allows people to do this. And before you all ask, I have no interest in using this information to my advantage, I think cheating in any game is pointless and a nuisance.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fll8e90"
],
"text": [
"It's more manipulation of a game engine than math. Each entity has an id, aimbots simply track the id and location and calculates where to put the sight based off how the engine handles physics. This is why each aimbot is programmed per game. call of duty for example is hit-scan so if sight is on the pixel of the enemy head on trigger pull it's an instant hit . Whereas battlefield has travel time for it's bullets requiring the bot to account for travel time, drop and velocity. While it all looks 3-d to us, Inside the game code it is still just from pixel a to pixel b based on the games physics engine. Sorry this isn't exactly the answer your looking for but since this is Reddit someone who actually knows in detail will be along soon to correct me and you'll get a better answer lol."
],
"score": [
16
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fpj9st
|
How are animated movies made? Like they can’t handdraw every single frame, right? How does that work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fll8jaj",
"fll8nvb",
"fll9n8y",
"fllabl1"
],
"text": [
"They used to draw everything. Now they use computers and software and facial feature recognitions and all that good stuff. Look into it, you might find a new interest.",
"Yes, hand drawn cartoons are fully hand drawn. The most recent completely have drawn cartoon movie was Netflix's [Klaus.]( URL_0 ) Other animated movies use CGI and motion capture. But most of your Disney classics were hand drawn. Every frame.",
"In the old days they drew every frame. However they draw the characters separately on clear plastic paper so they only have to draw the background once. Each frame is called a “cell.” Nowadays you can have a computer draw the movement between key frames, in a process called “tweening.”",
"So, this is one I actually have qualifications to answer! I have a degree in animation, but don't actually do it for work. It depends on the animation style and the technology available. Old Disney cartoons were all drawn by hand and, yes, they would hand draw every single frame. It was an incredibly time-consuming process. Some things made this easier; I never got into the full progression of this (as I was studying digital animation), but what some scenes would do was have static objects, like backgrounds and scenery, drawn on a piece of paper, and then every moving thing would be drawn on a clear sheet that would be overlaid on the background. That way you didn't have to redraw the same forest every frame, but just the characters in different poses. In a similar manner, stop-motion animation (of which \"claymation\" is a well known type) is done by building actual tiny models (out of clay in claymation) or using existing movable models like action figures, and moving them in tiny increments, taking pictures, then running those pictures as a film. Again: Incredibly time consuming, but this is how the Nightmare Before Christmas and the old nickelodeon show Kablam were made. Once computers entered the picture, the computer did a lot of the work of making motion happen once we had the code for it. In your typical digital animation, you're looking at keyframing and tweening. The words for this can change depending on the software, but I learned in Flash, so they're the terms I stick to: a keyframe is one that you set up so that everything is in the position the way you want it to look. You then determine how many frames you want a given animation to take, create a new keyframe that many frames away, and make an end-state of the animation. Then select them both and tell the program to create tweening, or the frames that come in between the two keys. It will then use the programming logic in the particular program to generate the frames between your starting and ending keyframe. Typically though, character animation is doing that a lot of times; for instance, you will likely need to make layers for each limb and different keyframes each time your movement changes either speed or direction. Some things are easier to just do frame-by-frame. In 3d animation, it's much the same: You transform the models and tell the software when the model should look like what, and the software fills in the blanks of how they get from keyframe to keyframe. As part of my life drawing for animation class, we had to create a flip-book, which is essentially going back to disney-style animating; we got a book of about 200 distinct pages and had to draw a little cartoon, page by page, that you would \"watch\" by thumbing through the book really fast. That was a very short bunch of cartoons, maybe 5 seconds for the longest ones, probably closer to 2-3 for most of us, but it took the better part of a couple of months for most of the class to do theirs."
],
"score": [
11,
3,
3,
3
],
"text_urls": [
[],
[
"https://www.itsnicethat.com/features/sergio-pablos-klaus-netflix-animation-201119"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fpjim9
|
how different fields of vision work and night vision.
|
I don’t understand How other ranges of colours work? Like night vision, IR, and etc... someone please explain.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fllbojf"
],
"text": [
"light is a huge spectrum of electro magnetic radiation; from X rays to radio waves it's all the same kind. a small part of that spectrum is visible light going from red to violet. beyond that, it's the same thing but a different color, one which we can't see. we can still make cameras that can detect theses colors. we can even change the hue that we detected and display it. allowing us to 'see' in the dark"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fppxsf
|
how do lava lamps work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flmd0fy",
"flmgerm"
],
"text": [
"Wax is heated up from a light bulb. As it heats it floats to the top of the lamp, where it starts to cool off. Once it’s cool it sinks back down and the cycle continues.",
"The \"lava\" is wax with density similar to water but more sensitive to heat changes. As the bulb heats the wax, it expands, reducing its density. Similarly, as it cools at the top, far away from the bulb, its density increases. In fluids, denser substances go towards the bottom. So it follows a pattern: Heat at the bottom, rise up. Cool at the top, fall down. Then repeat."
],
"score": [
16,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fpw4xj
|
How does the GPU work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flnbg59"
],
"text": [
"\"GPU\" is a bit of an abused term. When people talk about GPUs they typically mean the entire daughter board you slide into a [say] PCIe slot. These boards are effectively their own entire computer with their own power management, memory, memory control and processors. The processor part of a GPU typically (and I speak from the point of view of AMD since that's where I work but I imagine it's somewhat similar with NVIDIA) is actually made up of several processors. - The SIMD and shader sequencers which perform per vertex, per pixel, and compute operations on raw data. These execute \"shader programs\" typically written in a variant of C and compiled in realtime (via an API like OpenGL or DirectX) to shader instructions for the specific processor being used. - The Command Processor which takes a sequence of instructions from the program to load the various engines (DMA/memory controllers, shader sequencers, etc) with data and the requisite information to know what to do (e.g. pointers to the shader program to execute and pointers to the data) as well as configuration data (e.g. the format of the target bitmap, controls on floating point precision, etc...). There are often a slew of other processors - Security processors for HDCP compliance - multimedia encode/decode processors to handle full motion video - \"doorbell\" engines that allow user tasks to signal command processor sequences directly, etc. The GPU as a whole operates independently of your main CPU and can typically bus master system memory on its own, etc. It can signal the CPU when work is done via interrupts (IRQ lines) but other than that they operate independent of each other. edit to finish the thought: So when a program wants the GPU to do work they construct a \"command processor\" sequence of instructions (called an INDIRECT BUFFER in AMD speak) that are then fed to a kernel OS driver (called the KGD) and then the kernel driver will construct a similar command processor sequence that initiates the engine with a pointer to the programs indirect buffer."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fpweht
|
How do copper wires and fiber optics (light) transmit data?
|
Hi, I am currently studying computer networks and I have been reading about how data is transmitted via copper wires and fiber optics. I understand the very basics of computers, data, logic gates and binary code. However, currently I am struggling to wrap my head around how data can be transmitted by copper/light? It just does not make sense to me! Can someone shed light on this?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flnb915",
"flnaqli",
"flo0qtb"
],
"text": [
"Consider that you and a friend are on two hills far enough that your voices cannot carry but within sight of each other. You both have flashlights and know morse code. So by flashing the lights at each other you can send messages (ie data). Instead of flashlights, assume you have a wire between the hills and one side has a switch and the other a lamp operated by that switch. You can now send the same data by flicking the switches on and off according to morse code. Now replace the wire by a long internally reflective tube. By flashing a light on one end, the flash appears on the other, so you can send messages again. This is how copper wire and fibre optics work - just an agreed upon method to interpret the on-off signals. As long as both parties agree what certain sequences mean, then you can send information.",
"Copper is used to send electrical impulses that get translated into data. Same.. with light for fibre optic. One end transfers data to a series of impulses and sends them, and then the other side receives them and re transmits them back to their original form (audio, video, file, etc) This is the entire basis of how computers work, if you dont mind me asking, have you JUST started reading about computer networks and data transmission, or have you just ignored this part of it for a while?",
"Think about morse code. It's a series of long and short tones / beeps. And, people can known what someone is saying in morse code, by listening to those beeps, and assembling it into a message. * beep, beeeeeeep = \"A\" * beeeeeeep, beep, beep, beep = \"B\" * etc... Networks work in the same way. But instead of using sound, they use electricity (copper) and light (fiber optic). And, instead of beep / beeeeeeep, they use (on / off). But, they still rely on a pattern on / off / on / off messages coming in. And, instead of morse code and English, they use a computer code and language."
],
"score": [
33,
5,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
fpy5qt
|
How can Ambulance transmit warnings through motorists' radios?
|
The ambulance drivers can transmit messages into the nearby cars to alert any drivers not already aware of the oncoming vehicle. Adding this transmitter feature is part of Dubai Ambulance’s *Give Way Give Hope* campaign, which aims to reduce the number of delays caused by drivers blocking emergency vehicles. How does this work? Is it hijacking the cars radio?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flnl4tq"
],
"text": [
"> hacking radio waves? Somebody needs to watch less Hollywood hacking. Radio waves are not computers. It's like calling some guy running high beams behind you at night \"hacking your eyes\". The ambulance just has an ordinary radio transmitter. I don't know if it just broadcasts over all standard commercial radio channels or if it sends a message on a specific frequency that car radios specifically listen for and prioritize if present, but those are pretty much the two options there are for a system like this. EDIT: Yep, [it just broadcasts on a specific frequency and the car radios are programmed to switch to it if received]( URL_0 )"
],
"score": [
9
],
"text_urls": [
[
"https://twitter.com/Bu3osha/status/1184105351039336448"
]
]
}
|
[
"url"
] |
[
"url"
] |
fpzsl8
|
Why is there a waitlist on a digital library?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flntyyq",
"flntzlk",
"flnx922",
"flnuguk",
"flopln9"
],
"text": [
"I would assume it works like regular software and the library is only licensed to have so many digital copies of books in use at one time",
"Libraries have to pay for digital books, same as physical ones. The deals they have with the publishers only allow them to lend out as many copies as they have paid for.",
"Imagine if an unlimited number of people could check out a digital book from the library at a time. They would only ever sell one copy. If you were an author, would you spend two years writing a book if all you ever got was a one-time payment of $12.99 for selling a single ebook? Obviously this is oversimplified because there are still physical copies and not everyone is allowed to check books out from the same library (you usually have to be a resident of that city or county or whatever). But the larger point is that, in a world with digital distribution of books, authors and publishers won't be able to make any money unless you put some sort of artificial limit on how widely you're allowed to share digital versions.",
"Copyright owners and publishers imposed the rule that each purchased copy can only have one customer at a time. It is so they can sell more copies.",
"In order to comply with copyright laws, libraries have to own every item they lend out. Just like they couldn't buy a book and photocopy it, they can't simply buy one digital item and let multiple people use it. In general, if two different people in different places can use a single purchase, it is copyright infringement."
],
"score": [
21,
7,
6,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fq16ob
|
Why do video games 'bug out' and develop problems.
|
I know very little about game design and development but am interested to know how bugs appear in games, I can understand in the early stages of a game being developed problems arising and fixes needing to be made, but why in established games do problems appear such as lobby issues, crashes, etc.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flo259p"
],
"text": [
"Code is weird and complicated and it can be really difficult to be sure that it's going to do what it's intended to in every scenario, especially with all of the possible things that you can do in a lot of games. Some bugs won't have been discovered by the playtesters and that's why they still exist, others are deemed too insignificant or complicated to bother change. Because of the way coding games works, it's often not as easy as changing one little bit as it can have a knock on effect on other parts of the game. I know that some games such as final fantasy 7 have bugs that the developers knew about, but every time they tried to fix them, they broke the game worse in other places, so ended up just releasing the game with those bugs in it."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fq5dkk
|
How will ending encryption effect my life?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flotd6v",
"flopapm",
"flp0gn7",
"flp0pxs"
],
"text": [
"You will have no privacy online. All of your private messages, either from your computer, your phone, or anything connected to the internet, will be recorded and available to be read by anybody who wants them badly enough. Ending encryption is under the guise of catching people distributing child pornography, which it may help in doing, but it's mostly to trick people into giving up their privacy for \"the greater good\".",
"it basically means that anyone who wants to, will be able to access all the intricate details of your life. basically anything and everything about your life can be revealed. including all your chat convos and messages and anything you do, say, post, etc online.",
"So you have a crush on Brittnie. You write a paper note, fold it, and pass it down the row of desks til it gets to her. Only she reads the note. Without encryption, it’s like writing that message on a piece of paper without folding it. Anybody that passes that message across can read it. Anybody can peak at the paper as it travels down.",
"A few things that could immediately happen: - identity theft - financial account compromise - loss of privacy If you do things like online banking, encryption is what keeps things safe and secure. Otherwise, we’d be able to tell your account ID, password, and what transactions you were doing. Identify theft is huge — whether it’s pretending to be you but secretly/subtly or taking over your online persona as a whole. Think someone taking over your Facebook, Twitter, Reddit, Instagram, twitch, discourse accounts and locking you out for good. Loss of privacy will depend on your take. But just imagine ANYONE being able to read all your messages, regardless of who you talk to. Essentially, ending encryption makes it significantly easier for *anyone* (hackers, law enforcement, you or me) to know what you’re doing online. Imagine talking to someone (a bank teller, friend, loved one) in a room full of people. Encryption would be akin to you using a special language only you and the other person understands. Even if you were talking loudly, no one would be able to understand you, at least not easily. If you were writing it down, encryption would be like putting your message (in that special language) in a sealed envelope and maybe also signing on the seals — even if that envelope passed multiple hands, the recipient would know if it had been altered or tampered with."
],
"score": [
20,
14,
10,
7
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fq5jqz
|
How can people take old videos and upscale them to 4k?
|
The video that made me ask this is this one [ URL_0 ]( URL_0 ) A-ha: Take on me in 4k. How is this possible when 4k didn't exist when the video was made?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flopklt"
],
"text": [
"That video was recorded in 1985 on film from my understanding. Film itself has a resolution way beyond 4K depending on the grain size. As long as the film is preserved, it can be re-scanned using a higher resolution scanner. We will probably get an 8K cut in a few years."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fq7rkh
|
Sony just said they’re slowing their download speeds to preserve internet capacity for everyone. Is the internet a finite resource? Why can’t everyone just use the internet at once?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flp1jlv",
"flp1fa7",
"flp2zl4",
"flp24og",
"flp1s2p"
],
"text": [
"As far as I understand it.. think of the internet as a pipeline whenever you want to load a webpage or download a file you are basically requesting water to be sent to your tap the water being the information only so much information can be sent throw a pipe at a Time this usually isn't a problem because not everyone is requesting information at the same time so by slowing down how much information you can get everyone gets to use the pipeline As for why we can all just use it to it's full potential is because the pipes aren't big enough Lol hope this helps",
"The internet is not a finite resource and everyone can access it at the same time. What they are limiting is bandwidth. There is a finite amount of bandwidth every company can provide, which is why faster broadband costs more, because you get allocated more bandwidth. At the moment so many people want access consistently at the same time that Sony is obligated to provide more than they have access to, which usually would not be a problem because only a % of customers would use the internet at the same time. But with this crisis, they are effectively overbooked. They have sold more access than they can provide at once.",
"Internet providers oversubscribe. Suppose you have 1000 customers each with 100 megabit internet connections in some city/suburb/whatever. Logically that's 100 gigabit of capcity and you should be able to provide that, but since users normally don't max out their connections all the time you can easily get away with only having 1/10 that speed on the other end and only need 10 gigabits into the building where all those customers are connected from. Internet providers do this all the time. This is a huge cost savings and for decades it's worked. But things are different today than they were yesterday. Now those 1000 customers are at home ALL THE TIME, both parents and kids. The parents are trying to work and run video conferencing which is sensitive to internet hiccups. The kids are trying to watch Youtube and Netflix at 11 am. That's actually very atypical. Now that 10 gigabit connection to the neighbourhood doesn't cut it any more and everybody is suffering a little bit. And video conferencing suffering from internet problems turns into video and audio stutters pretty quickly which ruins the whole thing. Upgrading is difficult when the ISP employees are also trying to protect themselves from COVID-19, getting the needed parts is difficult because manufacturing and trade is slowed, and of course it's spending money that wasn't planned and there could be trouble getting the cash needed. So Youtube and Netflix are saying that users won't (by default) get the highest video quality available. That probably takes a good 20% off the bandwidth they're using, relieving some of the pressure on that 10 gigabit connection. And that is definitely appreciated by the ISPs if not by the users. Sounds like Sony is doing much the same thing.",
"The Internet consists of MANY different networks. What Sony is doing is preserving THEIR Internet connection. When you view something over the Internet, it comes to you in “Packets”. It takes a small slice of time for the Packet to go from one device (Router, Switch, Gateway,...) to the next and during that time nothing else can travel on THAT network segment. Everyone else has to wait. The bigger the “thing” being transferred the more Packets it takes. Now, the networks are FAST and are designed to weave Packets for different destinations together to no one user can appear to monopolize the link. But if enough people are trying to get content from one source, it starts to become a problem.",
"It's like lots of roads leading to bigger roads, then highways, freeways, interstates. Like the major freeway in LA during rush hour. Can't just keep jamming cars in there. All the intersections can only handle certain amounts of traffic."
],
"score": [
13,
6,
6,
5,
4
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fqamvq
|
How large is the internet?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flphp9t"
],
"text": [
"There's no single answer, and there's no real way to know: we can only estimate Why is there no single answer? - Duplicate data: lots of images are duplicated, Netflix stores all their movies on different servers around the world to deliver them faster, people have copies of the same data. Are you keeping one copy, or every copy? - Are you including the WHOLE internet, or just the publically accessible parts? How about company networks? What about forums that are protected, hidden subreddits etc, are they beng included? Does that mean you're saving a copy of every single person's bank statements available from their bank's websites - Some parts of the inernet are dynamic: if you go to somewhere like [This Person Does Not Exist]( URL_0 ) you'll get a different picture every time... how do you know when to stop retrieving it? - Are you retrieving the source code, or the output? Or both? - It changes all the time, doubling about about every 2 years Roughly speaking, though, the amount of publicaly-accessible data on the internet is estimated to be somewhere around 8 million exabytes ( 8x10^24 bytes) by 2020 That's 8,000,000,000,000,000 GB, or 1,000,000,000,000x 8TB Hard Drives, costing $150 each"
],
"score": [
4
],
"text_urls": [
[
"http://thispersondoesnotexist.com"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
fqfdny
|
How do nature docs get such spectacular footage and audio?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flq5tak"
],
"text": [
"For the footage, time a lot of time. They have multiple crews going out to catch the footage they need and they spend a lot of time sometimes a year or more scouting and staking out locations and animals to get those 2 minutes of footage. As for the sound they have good dorectional microphones like what you might think the CIA and FBI use, but a lot of it is enhanced with Foley artists. Essentially they're just people who take the normal footage and add sounds similar to the quiet nearly inaudible sounds the mic's pick up in the field. For instance a bird's wings flapping close up might be recreated with a feather fan in an isolated sound studio or a splash will be a bucket of water dumped onto a floor."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fqlf8j
|
What is the difference between "Size" and "Size on disk?"
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flqvmxx",
"flqznf9"
],
"text": [
"In a really simplified sense: think of a storage device as a book: storage is divided logically into discrete \"pages\". Each page can only be assigned to a single file, so if that file doesn't occupy the entire page, the rest can't be used by anything else since the table of contents points to that page for the first file. This is why, especially notable for a small file, the \"size on disk\" statistic is often a even multiple of a power of 2 (like 4kb, for example\")",
"Think of it like a spaghetti sauce. Let's say you have 10 litres of sauce that you want to store in five containers. But all your containers are 3 litres, so you put 2L of sauce in 5 containers. The \"size\" of your sauce is still 10L, but the \"size on shelf\" (or on disk) is 15L."
],
"score": [
19,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fqmyfg
|
how do mouse without the red light/ball work?
|
I recently bought a new wireless mouse. So far, all the mice I've ever seen had either a red light at the bottom (IR im guessing) and I suppose that's how it works. Or, even older, the little ball mice used to have. But this new one does not have either of them. It does have a similar hole like those with the red light, but no light at all. How do these work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flr2xa6"
],
"text": [
"Well, the \"red light\" on an optical mouse is really just that - a red light emitted by an LED. The mouse you have now is actually projecting infrared light, which is why you can't see it, because humans can't naturally perceive light in the infrared part of the spectrum. If it's a \"laser\" mouse, then it's using infrared lasers to do the same thing that the LED \"optical\" mouse is doing (even though they're both technically optical). How they work is kind of like how a bat's echo location. Except with light. It projects light, sometimes directly downward or sometimes through small mirrors/lenses, and then tracks the light particles as you move the mouse around. It translates that back into motion that the computer registers to show the appropriate motion on your screen. As you can imagine, it has to do this very, very quickly since you see it all happen in real time."
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fqwop1
|
Why do wifi routers have multiple antennas?
|
I know that wifi routers are essentially weak microwaves but wouldn't multiple antennas cause interference or so?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flsp3jv"
],
"text": [
"Since WiFi has to operate in complicated environments, and the chances of signals reflecting off of surfaces before reaching a device is high, There's a real probability that for example, some of the signal could take a more direct route, some could take a less direct route, and they could arrive 1/2 a wavelength apart. this would make the signals destructively interfere and produce a signal dead spot (one reflection is positive as the other is negative, so they cancel). To fix this, having two antennae broadcast the same signal at 1/2 a wavelength apart means that the same set of reflections has to happen twice, which brings the probability of a signal 'dead zone' down. This is known as signal Diversity. In more modern routers it can be used for 'beam forming' where the router and device can establish a frequency that produces the least destructive (or most constructive) interference, and the router can produce 2 out of phase signals that fit this profile best and cause constructive interference at the device. Sorry this ELI5 got a bit technical"
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fr1gti
|
How does answering a recaptcha prove that you’re not a robot?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fltbpbs"
],
"text": [
"The advantage of bots is that they work directly on the level of the computer, so they don't have to do slow, inefficient things like physically moving a mouse, identifying what the screen shows and where they need to click, aim the mouse it, etc, they can just say \"put cursor at 600,400\". Capchas pose a simple to solve logical problem that strictly needs those slow, inefficient methods humans use(looking at the screen, understanding written instructions), so simpler bots can't solve them, and bots that *could* solve them would need to include complex features like image recognition, basic interpretation of written, human language instructions(both things that kind of just come \"for free\" for humans, but need a lot of work for computers to be able to do it), and *then* the capcha still checks for things like speed and precision of the inputs, to make it even harder to fool the system. It isn't impossible for a bot purposefully written for that to fool a capcha, but in fooling it, the bot is forced to be as inefficient as a human would be, and in most cases, you might as well just use humans for the same purpose instead of spending a lot of time putting together a complicated bot. edit: Also in the early days, many capchas were simply lies. They'd let you through even if you left the answer blank, or wrote any random thing. Those weren't there to keep bots out(the input checking might have been already in place, so it gave *some* defense, but giving a right answer wasn't mandatory), but to use the humans to build a database of images and a description of them(or transcripts of scanned in text), which *then* could be fed as training data for image recognition AI."
],
"score": [
21
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fr42in
|
why do screens often have odd pixel amounts like 1080 or 1440? Why not even number like 1000 or 1400?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fltoqfx",
"fltq39y",
"fltyv8g",
"flu5l9w",
"flu3k6t",
"flu7yqa"
],
"text": [
"> There are historical reasons: > Back in the day, analogue television had limited bandwidth. They used that bandwidth as well as they could and came up with a standard to transmit luminace and chrominance plus audio in that limited bandwidth. Later, when color TV was invented, they had to retrofit more chrominance information into the same bandwidth. The number of lines per second they had to transmit was also constrained by further historical reasons: electricity frequency, which goes back all the way to Tesla, the beginnings of AC, and electric motors. So, NTSC (used in the US) settled for using their 6mhz of bandwidth to transmit a 720x480 image at 29.97FPS. Other standards, PAL and SECAM, for instance, used a higher resolution at a lower framerate (720x576 @25FPS). Again, this was constrained by the fact the US uses 60hz AC, while PAL/SECAM countries (Europe, South America) used 50hz. This where interlaced signals (each frame is actually split in two and transmitted odd / even), that's why framerate is half the electricity frequency. > With the advent of digital, this same resolutions where used as a starting point. VGA was based on NTSC (640x480). As LCD screens became the norm, progressive video replaced interlaced, and 480p became the standard. Since video needs to keep its aspect ratio, both width and heigh will grow proportionally. > So, 720p is simply 1.5 times 480p, and 1080p is simply 1.5 times 720. > 480 * 1.5 = 720 720 * 1.5 = 1080 CREDIT: /u/gnualmafuerte who answered a similar question 6 years ago. I thought it was an interesting question. I had an idea of an answer that was wrong. It is not because of binary or hexadecimal numbers. In the course of fact checking myself I came across this answer which is muy fuerte. He is quoted in full above.",
"Old CRTs in TVs or monitors had displays had a ratio of 4 wide by 3 high. Most numbers for displays come from simple relationships from that. For instance 16:9 in a wide screen TV is 4^2 by 3^2. The original 1987 VGA standard for computer displays was 640x480, as was PAL TV. 1920 by 1080 is 3 times 640 wide in a 16 by 9 aspect ratio.There are only a few occasions where both numbers in those relationships come out to round numbers (800:600 is one) Here is a graphic of display resolution standards going back to old CGA 320x200 pixels. You can follow the aspect ratio lines to follow the relationships. URL_0",
"Technically they are all even they end in zero I think you mean more like round to the second or third digit",
"There is nothing special about 1000 or 1400. They just look special because we use the base 10 number system.",
"Other users have already explained the historical context. On top of that, powers of two work better for computers for various reasons. If you factor all those numbers, you'll see they have a ton of 2 factors. For example, 1920 is 2^7 * 3 * 5. This is how we wound up with 320x240 and 640x480. NTSC has 525 lines in the signal, and how many are visible is actually kind of variable, because back in the days of CRT TVs it just depended on exactly how the image was aligned (CRTs don't have nice perfect rectangular screens). 483 was about right. Then when computers started getting into the picture, that got rounded down to 480 (or 240 in progressive / double strike mode). That's how we wound up with a number that has a lot of 2 factors, because it got rounded like that for computers. Same reason you have 16GB of RAM, not 15GB.",
"[ URL_0 ]( URL_0 ) This guys youtube channel is awesome for technical questions about common household technology as well as some geekier niche stuff."
],
"score": [
267,
41,
27,
8,
6,
4
],
"text_urls": [
[],
[
"https://en.m.wikipedia.org/wiki/File:Vector_Video_Standards2.svg"
],
[],
[],
[],
[
"https://www.youtube.com/channel/UCy0tKL1T7wFoYcxCe0xjN6Q"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
fr45gv
|
What makes the touchscreens of smartphones feel different from the touchscreens of Nintendo DS's/3DS's and older mobile devices ?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fltmvd3"
],
"text": [
"Your phone uses a capacitive touch screen which uses the capacitive properties of your finger to detect where you are interacting with the screen. Resistive touch screens have a flexible surface that when flexed allows two conductive surfaces to interact Resistive screens need to flex under pressure so they will feel different then capacitive screens which are rigid."
],
"score": [
19
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fr95q0
|
. How can forensics identify whether a file has been copied?
|
Also does this mean that when you copy and paste something, the copy is never identical? Can they identify how many times something has been copied from the original file? Thanks!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flvnrqn"
],
"text": [
"Oh, i work in security and have done forensic imaging of computers before, so i get to chime in with coming from the field! so, when you do things on your computer, they are logged. So for instance, when you plug in a USB drive theres a log entry for a new device being found as well as a log item for it being mounted. based on things like the id of your flash drive, i can see that it is infact a flash drive. similar things can be logged for when a file is copied, such as the time the file was last accessed. if the access time on a file happens to be between when a flash drive was mounted and removed, chances are it was copied to the file. forensics tools will give a timeline of events which makes this kind of behavior real easy to spot. as others have mentioned, if you have the file on the flash drive, you can look at file metadata to see when it was created. if files are uploaded to an online site, the PC has to translate the website (such as URL_0 ) to an ip address. your pc caches these so they dont have to continuously do the lookup. we can look in the pc's dns cache to see when that happened. enterprise network hardware often will keep logs of what ip connected to what, so thats another source of info. ________________ to address the two questions you asked: no, when you copy a file it is identical other than the metadata for the file (which isn't on the file its self, but on the filesystem you store it on). for instance a fat32 flashdrive stores a lot less metadata than an ntfs or exfat drive. if you have the source machine that has the only copy of the file, you might be able to tell how many times it was copped from that, but you have no idea how many times it was then copied from that copy."
],
"score": [
5
],
"text_urls": [
[
"dropbox.com"
]
]
}
|
[
"url"
] |
[
"url"
] |
frdiua
|
How do CPUs have such a high wattage and such a low voltage?
|
Most CPUs run at less than 2 volts, yet they pull more than 100 watts. Surely they don't have 50amps running through the tiny traces?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flv62yg",
"flv63oi",
"flv621l",
"flv6sj0"
],
"text": [
"yes, they do. They run at such a high speed that the transistors are always switching, and therefore they're pretty much always in their linear region and burning power. They tend to have upwards of 8 seperate power phases for high end CPUs. Look on the motherboard, near the CPU there's a bunch of massive inductors. each one is a power phase.",
"Not through each individual trace, but remember there are BILLIONS of transistors inside them and so there are a LOT of individual traces. Similarly many of the pins on the CPU are for power in/out and not just a single input and output. Also the voltage is more like 1.3 volts. And yes, there is 77 amps (`100 / 1.3`) amps coming out of the VRM (voltage regulator modules) heading towards the CPU. It scatters around, but it's there. Finally that is supposed to be a worst case number. You'll hear the CPU get busy as the fans spin faster to cool the CPU. Most of the time it'll be much lower, and the voltage may even come down.",
"They have many, many traces. The goal of low voltage is to reduce power consumption, it takes fewer electrons to charge up a gate to 2V than 3.3V.",
"They have very large traces connecting to a huge amount of power and ground pins. Around the CPU you'll see a dozen capacitors and probably some square box inductors as well. These are the voltage regulators that step the CPU power down from 10A at 12V to 100A at 1.2V that the CPU needs to run. All this will hop into a very large copper trace(generally called a plane or pour) to get to the CPU socket where it will then join up with the appropriate pins, and there are a lot of power and ground pins going to the processor. Intel LGA 1151 sockets have about 150 power pins and nearly 400 ground pins to carry all the current the processor needs Once inside the chip there is going to be a thick amount of copper running around the chip serving as power and ground as all transistor sets need access to it. These tiny copper wires each carry a small amount of current, but a million copper wires each carrying 100 uA is 100A of current! This is why heatsinking is so important for a CPU, all the power that it uses gets turned into heat"
],
"score": [
9,
8,
7,
4
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
frdopz
|
Why do podcasters and broadcasters wear headphones while talking/broadcasting?
|
So I think I get the broadcast part: you have to communicate with other team members, staff, TV channel etc while broadcasting and commentating a basketball match. But what about a podcast episode? Take Joe Rogan's podcast for instance: every time when he uploads a new episode you can see he and his guests + Jamie wear headphones, while there there is noone outside to communicate with, no organization or anything. And also, you may notice there are episodes when he doesn't wear them. What makes the difference?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flv7dp9",
"flvbwj8",
"flvhcoy"
],
"text": [
"To block out ambient noise, and so you can hear if you're talking loudly/close enough into your mic.",
"Prevent feedback. If you have music or others sounds going on during the broadcast, you can't have those sounds piped through speakers where when the mic is live. So, usually, the mic switch turns off the speakers in the room when the mic goes live. When that happens, you can't hear anything other than your own voice. You can't even tell how loud your voice is being broadcast. At least, that's how it worked in the radio station I worked at when I was younger.",
"Because what you can hear in the room isn't necessarily what the microphones pick up, and you want to be able to hear what is being recorded/broadcast. Back in my university days I worked on the college radio station and one of the first things you learn is mics have an optimal range. You don't want the gain on the mic to be too sensitive (you don't want to pick up any unwanted noise and you don't want 'cross talk')...and, especially with condenser mics, if you're too close, your voice gets way to bassy and 'boomy' and if you're too far away you sound distant and tinny... and the difference between too close and too far can be just a few inches. So, when you're wearing a headset, you're hearing what the microphone is hearing. It's easy to tell if the mic is picking you up properly or if you're too close or too far away. I remember it being absolute murder if we had too many people in the studio and didn't have a headset for everyone. People tend to fidget and don't understand that just leaning back in the chair or turning their head is enough to make their audio unusable. Every two minutes I'd be making hand signals to remind the person to talk to their mic, not to me."
],
"score": [
18,
8,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
frgqfr
|
Why to light bulbs burn out after a few months but computer/tv screens last for many years?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flw2wjg",
"flvoqlu"
],
"text": [
"Light bulbs don't burn out in a few months, at least not anymore. Old-style incandescent bulb that heated a filament to yellow hot burned out, but modern LED bulbs use the same technology as computer screens and can last just as long. Also, when a LED element on a screen fails, you get a tiny black dot, sometimes so small you don't even notice. When a light bulb fails, the whole thing fails.",
"You might be thinking of incandescent light bulbs. They work by heating up a filament to be so hot that it glows very brightly. It would corrode very quickly in air at that temperature, but they put a near-vacuum or inert gas in the bulb that lets it glow for a lot longer before it disintegrates. Screens have never been incandescent. The older style was cathode ray tube (CRT) which is most similar to a fluorescent bulb. A stream of electrons is shot from the back to a sensitive plate at the front that glows when hit. Modern ones are most commonly liquid crystal display (LCD) or other technology that's a bit more sophisticated as well than \"heat something up really really hot.\" So they don't suffer the same limited lifespan. You can get light-emitting diode (LED) bulbs nowadays that similarly last a very long time and are really cheap to run. *That said, apparently it is possible to have incandescent bulbs last a looooong time, but there was a business agreement way back in the day to give them a reduced lifespan. This way they could sell a lot more bulbs rather than have people only buy them when they get violently broken."
],
"score": [
6,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
frh41d
|
How are IP addresses identifiable by location?
|
How is it that services are able to know the exact real-world location of a public IP address? Is there some prefix or suffix that gets linked to that location, ISP, or organization? Do these services just perform a WHOIS lookup?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flvrnpv",
"flw7btc"
],
"text": [
"Blocks of IP addresses are assigned to organizations on request by a handful of non-profit organizations responsible for maintaining the IP space. These are the Regional Internet Registries. In North America this organization is ARIN, in Europe its RIPE, in Asia it's APNIC, etc These organizations each have certain number of IPv4 and IPv6 ranges that they can issue to companies upon request. When you get an IP range assigned to your company or organization it's registered into their database along with your head office location. That's what defines those IP ranges as belonging to a certain country + state + town. We don't usually think about top-level organizations like ARIN though, because most people and companies get their IP's assigned to them by an ISP. But the ISPs in turn get their IP ranges from ARIN, RIPE, etc Only very large organizations tend to get dedicated IP ranges all to themselves. Apple, HP, and the US government for example have massive IP ranges that belong to their organizations.",
"1. Static addresses assigned by an ISP are linked to a company and location. 2. For most residential cases, dynamic addresses assigned by an ISP are leased for a limited amount of time. You go through multiple addresses every year. These addresses are linked to you profile while they are leased to you. Your profile holds your address and contact info. In terms of geotagging, many factors contribute to your Geolocation which is encompassed in a term called Metadata. Some apps ask for the permission to use info such as GSM, GPS, ISP info, carrier info when you use their service/app/ and even browser. Thus, pizza pizza knows the closest location to you is the one down the road because google chrome gave them that info. Same goes with Google Maps. It gathers everyone's gps coordinates that use the app. Therefore, it can give you the quickest route by determining how many users with their GPS enable on the road."
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
frjk7a
|
How do computers read code?
|
I was just wondering how computers read code. Wouldn’t you need to program the computer to read code? How does it work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flw708u",
"flw7d6z"
],
"text": [
"It depends on the *language* of the program. A computer is a machine techically able execute one specific language only, called for this reason its *machine language*. The machine language is made of very simple instructions, such as summimg two numbers together, or loading one number from memory. These instructions are so simple that we are able to construct a circuit (which is basically the computer) *physically* able to execute them. When the computer executes a *program* in *machine language*, which is just a long sequence of these instructions, it works like this: it phyisically loads the instructions, one after the other. The instruction really travels in specific cables in the circuit, and it lands on another piece of the circuit, where it triggers one or another physical parts of the circuit used execute that specific istruction (like the sum). It's literally a physical, mechanical process (well, electronical). But the *machine language*, being simple enough to be understood and executed by a machine in this way, is also too simple for us to write anything useful with it. Instead, we code the computer using more complex and powerful languages, called *high-level languages*. That's what coding is: writing a program in some high-level language. No computer can directly read or understand any of these languages. To be executed, the program must first be *translated* into machine language. The translation (called \"compilation\") is performed by... another program, called \"compiler\". The compiler itself can be executed by the computer, because it is written in its machine language. So, you may be wondering, how was the first compiler made, given that we can only code programs in high-level languages, requiring to be translated by a compiler before they are executed? That problem had to be faced (only once!) in the history of informatics. There are several solutions, such as manually translating your first program, with pen and paper, just that once, and inputing the machine language code directly on the computer.",
"We build machines to build bigger machines. A screwdriver might be used to assemble a power drill. We then use the power drill to build a tunnel boring machine. At the lowest level, computer code are electrical signal going through logic gates and producing electrical results as output. The gates are combined and chained into more complex sets of gates. As it goes higher and higher level, they are written as instructions to which set of gates to execute. Computers translate these instruction programs into lower level instructions and ultimately run a set of logic."
],
"score": [
16,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
frk2fl
|
why devices don't accept fingerprints after restarting or updating
|
if I restart my phone it says "pin is required for restart" and on my computer says "use password for fingerprint". why is it any different for when I'm normally logging in?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flw8i82",
"flwedsn",
"flw8be1",
"flx1wue"
],
"text": [
"It is for your protection. You can be (legally/forcibly) compelled to give your fingerprint. You cannot (in most states) be compelled to give a piece of information held only in your head. If you want to protect your privacy, say at a border crossing, you could restart all your electronics. Even if you are detained and forced to provide biometrics, your devices remain secure. This is part of the reason that the USA and other governments want encryption “backdoors” to be built into phones. With strong encryption, guess limits and lengthy PIN, it can be challenging even for states to break into properly secured consumer electronics.",
"You can use a pin as an encryption key (because you can type it exactly correctly) but you can't use a fingerprint as an encryption key (because you need to be able to accept imperfect matches)",
"A variety of factors. To prevent people from logging in with your biometrics. To disconnect the Secure Enclave when you’ve shut it off because of security/encryption. To make you just use and remember your passcode from time to time",
"Fingerprints scanners (or even face recognition) on mobile devices and laptops are pretty basic and aren't as secure pins or passwords, they are used for convenience rather than true security. You can only enable fingerprint scanning on these devices after entering the more secure password and you are essentially telling the operating system, \"I'm okay with using a less secure method to unlock once I've entered my password\""
],
"score": [
528,
69,
16,
4
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
frn0mj
|
Why are mobile games companies seemingly immune to copyright and plagiarism laws ?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flwqhi7",
"flwn8ht",
"flwza8u",
"flwq12o",
"flwxsps",
"flwz6nb",
"flwzm4y"
],
"text": [
"Some of it is the Hydra effect too: they're being shat out faster than they can be taken down..",
"I believe a lot of them have origins in China where they don’t seem to care about western copyright law.",
"The short answer is they're not. The longer answer is that copyright is specific to certain aspects that maybe you wouldn't expect. Saying it fairly generally, [style]( URL_0 ) cannot be copyrighted but characters can. Exact images can. Meaning - you can make a 2D image of a character that looks similar to another, but you cannot trace your character on top of an existing 2D image of a character. You cannot copyright [perspective or UI elements]( URL_1 ?) that display health or other gameplay information and you cannot copyright very generic words like Health - but you could copyright very specific gameplay terms like a tetris. Games like FPS games, sports games, racing games, and other very broad game concepts cannot be copyrighted because... well, there would be absolutely no competition and it just wouldn't make practical sense in a society.",
"That zombie game I've seen advertised to shit on Reddit lately has a fucking Boomer from Left 4 Dead as an enemy zombie. Pretty sure it's ripped other assets, too. I usually blame China or people who are so small time that the bigger companies don't even know they're doing it.",
"For real! How many clones of Pokemon games do I see ads for on totally legit apps such as Instagram. And the app is sitting there on the Play Store with millions of downloads while it has nothing to do with Nintendo or Game Freak. I have no idea why nothing is done about it. If it's just Chinese devs not giving a fuck you'd think Nintendo would have already sued the shit out of Google for allowing these apps on their store.",
"Videogames fall under what’s called the transformative use test. Putting it really simple, you can take “inspiration” from something copyrighted and “transform” it into something seemingly “different” and be completely and legally clear. Simple example is removing something from it’s traditional setting, creating a football video game that takes place on another planet with “inspiration” of legitimate NFL players would more than likely Be okay.",
"There are too many of them for the existing systems to cope. I've seen Instagram ads where they were using screenshots from Age of Empires 2 to link to unrelated mobile games. In that case, like in all the clones you will find, somebody needs to report and file complaints for Google/Facebook/Apple/etc. to notice and take action. Publishers do not have the resources to browse the various app stores all day. That's how those rogue companies go about making a quick buck. It will continue until the app stores and ads platforms put better reporting systems in place."
],
"score": [
307,
200,
111,
48,
13,
9,
7
],
"text_urls": [
[],
[],
[
"https://www.thelegalartist.com/blog/you-cant-copyright-style",
"https://www.newmediarights.org/guide/legal/Video_Games_law_Copyright_Trademark_Intellectual_Property#What%20parts%20of%20the%20video%20game%20are%20copyrightable"
],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
frqxis
|
how does a computer know how long a second is?
|
How does a computer know exactly how long a second is? Does it know it as a rhythm? Does it know it by a certain number of computer thingys to equal one second (like unit conversion)?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flx5wra",
"flx654r",
"flxai7x",
"flx60sd",
"flxacmt"
],
"text": [
"There is a clock on the motherboard driven by a quartz crystal that vibrates at a fixed frequency. That is connected to a counter chip that simply tots up the number of pulses from the crystal and sends out a pulse of its own when the count reaches a certain value, the number of pulses in a second. It's just the same as the way billions of digital clocks work. It's the reason that there is a small battery on the motherboard, to power the time keeping circuit even when the power is off.",
"Computers have a \"real-time clock\" which is powered by its own battery that's always running. This clock is also updated when the computer connects to internet. This clock is then used to measure time intervals. The clock uses crystal oscilation to generate a solid frequency used to measure time.",
"The ELI5: You know those sprinklers that go tk-tk-tk-tk and sort of work their way around in a circle... But make that constant ticking noise at a fixed rate. So imagine the electricity is the water. The mechanism vibrates when a constant water source is connected. There's a circuit that does this too, and since you know it \"ticks\" at a specific rate, you can count time with it. More specifically, it's a crystal/quarts oscillator. It turns out that quarts, depending on how it's cut, produces a an AC wave at a specific frequency when driven from a DC source, convenient! So these extremely accurate crystals are what's used for that. Hopefully that makes sense! -edit: a typo",
"There are a few ways a computer can keep track of time. 1. Internet synchronisation - a central Web server broadcasts the time for every timezone. The computer needs an Internet connection to be able to be in sync. 2. Built in clock - if you saw a naked motherboard, you'll be able to see a coin-like battery (the same type they use for watches). Even though the computer is disconnected from the Internet, the battery can keep the internal clock ticking so that the computer will still be displaying the correct time when you turn it back on (without net connection). For the more technical answer, modern timekeeping is based on atomic clocks. Atomic clocks measure the number of oscillations of a cesium atoms. Really complicated and mathematically heavy but let's just say scientists pegged the length of a second to the time a cesium atom produces a particular number of oscillatotions/atomic vibrations.",
"Lot of good (bit dated) answers. Most PCs and embedded computers keep track of time using cycle counters based on knowing the clockrate of the processor. Cycle counters are highly precise counts that can be used to get more precise timestamps (down to nanoseconds). Desktop/laptop PCs have \"realtime clocks\" (RTC) that track time when the PC is off/suspended but they all pretty much use cycle counters while active. As others pointed out a lot of net connected devices use Network Time Protocol servers to sync up time (whether they have a RTC or not). These NTP servers either have their own high precision clocks or are themselves synced to them in highly reliable and controlled fashions. edit: Should add this is the distinction between \"time\" and \"counters.\" Most computers really only employ counters (count cycles, seconds, etc) but aren't time keepers."
],
"score": [
216,
22,
19,
6,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
frtl94
|
Why does erasing an entire hard drive take less time than deleting some individual files?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flxku7s",
"flyf8un",
"flxrqnb",
"flxlg3q"
],
"text": [
"* Hard drives keep list of all the files and where on the drive they are located. * When a new file needs to be written, the hard drive controller checks the list to find a free spot. * When you \"delete\" a file, you are just updating this list to say that spot on the hard drive is now available for a new file. * When you delete the entire drive, you basically just delete the whole file, instead of having to load the file and check for the entry for a specific file that is being \"erased\".",
"Imagine a box of lego. Now imagine you're told to throw out the whole box of lego Or pick out all the yellow 2 x 4 pieces That's wiping a drive vs deleting individual files",
"The hard drive doesn't actually erase anything. The computer is just allowed to write on top of the files now.",
"Erasing an entire hard drive can be as simple as deleting a VERY small group of data telling the system what parts of the drive are assigned to what partitions (containers of filesystems). (In the old MBR partition scheme, the very first few bits of the drive contained little more than a pointer to up to four partitions (each of which can contain a filesystem) and a bit of code instructing the system what to do in order to boot up). This record was limited in size to just 512 bytes if I recall correctly. (Not even the size of a floppy disk) The individual filesystems don't need to be modified, since the pointers to them have been erased."
],
"score": [
13,
12,
5,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
frtvqk
|
How do search engines find their URLs?
|
The internet is huge and not in one place, so how do we know they searched everywhere?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flxnj4o",
"flxnqbg"
],
"text": [
"Search engines \"crawl\" the internet to search for content that will satisfy the user's search. Website devs need to optimize their website so they can be indexed (or \"crawled\") and they also includes optimizing the URL so it can be crawled. Optimizing (being relevant being one very key point) also helps your search engine result page (serp) rank increase (showing up as first result is most desired because 75% of us don't go beyond the first page of SERPs), but without going into marketing, that's the basics",
"You start off at a single URL and then follow the links on that site. Then you follow the links on those sites, and those sites, and so on. Eventually you will come to a site which does not have any links, gives you an error message or sends you to a login screen. So you are not able to get everything. However most public sites will have some other site linking to it. And in the rare case where there is none then it is unlikely that you will miss it from your search results. It is estimated that the best efforts of Google which have indexed the most websites of anyone have been able to find about 2% of all websites. The remaining 98% is considered the dark web and includes things like closed Facebook pages, your attempt at blogging in high school that nobody linked to, your companies internal website, etc. Of course some of the dark web is used for criminal purposes as they do not want to make the job easy for the police to find them."
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
frudfd
|
Why does IPv6 Adoption correspond to the day of the week?
|
I'm learning about Cybersecurity and my course referenced IPv6 adoption for 3 years ago. I found the current rate from [Google is on avg 30%]( URL_0 ). However if you look at the graph it's a noticeable pattern that corresponds to the week. Sunday is almost always the highest IPv6 traffic with Monday often being the lowest adoption. Why is this?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flxtnjc",
"flxu1k8"
],
"text": [
"IT administrators do most system maintenance, configuration changes, and updates during the time when the network is least being utilized and thus causes the least amount of network disruption. This is generally late Saturday night or the wee hours of Sunday morning. You wouldn't want to take down the network or make significant changes in the middle of a workday, especially if something doesn't go right. The weekend also gives you time to adjust fire as they say in case anything goes wrong.",
"The chart shows the proportion of IPv6 relative to the total and not absolute usage That suggests, that private/home users are more likely to use IPv6 than organizations. One reason could be, that organizations with their complex networks struggle more to make the switch, and since IPv4 continues to work, they have little incentive to do so. Private/home users typically have much simpler setups and the switch usually happens automatically, when their ISP enables IPv6 for them. So as far as home/private users are concerned, the chart shows IPv6 readiness of ISPs rather than conscious choice of private users."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
fs3egb
|
Why do the files on a smartphone not become corrupt when it runs out of battery power, but it would happen to a games console?
|
What is it that is different?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flz7bsf",
"flz9tb2",
"flzjddn"
],
"text": [
"Smartphones rarely ever shut down. Also, when your phone gets down to 0% battery, it's not actually at 0%, it can be anywhere from between 5% and 20% actual charge. This is because the battery needs to have a little bit of power to continue working, and also gives the operating system enough time to do a proper shutdown.",
"What modern game console get the result in the corrupted file if it runs out of battery power? It should be trivial to implement saving to handle that situation. File system that can handle power cuts like that is common today. For files you do not write to loosing power should have no effect.",
"It comes down to the file system that the system runs. In essence, there's a thing called \"journaling\" which keeps track of how things are changing in a file as it happens to allow for recovery if power fails. Consoles don't have this feature so when power is lost it doesn't have a journal to see how to fix the file if it gets corrupt. Edit: If you would like to look into this a little further in-depth, look at NTFS (journaling file system) vs exFAT or FAT32 (the 2 file systems PS4 supports) both of which don't have journaling."
],
"score": [
9,
5,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
fs3po8
|
Why is a greenscreen green?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flz9k22"
],
"text": [
"Cameras have red, green and blue sensors and you get the sharpest image out from a color that just stimulates one color. You could use any color to do what has the general name chroma keying but red, green or blue has the best result Human skin color contains a lot of red so it is not used with humans subjects but can be used for other stuff. That leave blue and green and both common to use. On the reason that you see green more then blue is that is an uncommon color in our clothes but blue is common. Another is that because human vision is most sensitive to green light because we have evolved in areas with lots of green plants that we needed to distinguish. So most cameras have 2 green sensors for each red and blue and the result is that green results in the sharpest edges."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fs66j4
|
How does wearable tech like Fit Bits and Apple Watches track our sleep cycles to show different stages of sleep throughout the night?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"flzoete",
"flzry6b"
],
"text": [
"They don't track your sleep, they just say they do, but they don't actually do it in a legit manner. Thats the real deal. Tracking sleep is actually a really complicated process requiring some complex specialized equipment and conditions. These devices just magic up some estimate that basically takes into account generally just the amount of movement you do while sleeping overnight and some data regarding your heart rate. There is no indication this is a good measure or that these devices are accurate, nor is this how an actual sleep study would take place. That is unless you look at one single study that says they are just as accurate and good as more complicated sleep tracking devices... you know, the only study that says it works... paid for and conducted by fitbit... hmmm.",
"The algorithms they use are fairly simple. The accelerometer in the devices detect motion. The heart rate monitor, well detects you guessed it heart beats. The combination of both can detect sleep to a good approximation. REM sleep, which is indicative of good sleep would require more sensors, not possible with simple devices like fit bits."
],
"score": [
14,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fs97uu
|
Why can games render high-quality graphics in real time, while rendering the equivalent in softwares takes minutes?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm055gf"
],
"text": [
"Game engines cheat. - They use low(er) quality assets (textures, models, animations etc). A character model in a video game will not be as complex as the model in an animated film or whatever. The movie character will have better hair, *much* more complex skin features, much higher poly count, you get the idea. Same goes for everything, really. A car in a video game won't look nearly as good as what Blender can produce. Moving liquids in video games always look bad even with today's technology. - They use different quality assets for different things. Imagine a scene where 2 characters are walking on the street. In an FPS videogame, all that matters to the player is the other character that they're walking along with. That guy is the only one that really needs to look good. The player character itself won't be rendered at all, and all the pedestrians and whatnot in the background that the player probably won't even notice can be rendered using much lower quality assets than that important character. If you're rendering a scene for a movie or a video or whatever, you generally make sure everything else looks good too. - They approximate, fake, or straight up don't do a lot of the things a proper rendering engine takes its sweet time doing. Rendering engines use very complex lighting models to simulate how the light falls onto objects, changes, bounces off, and hits other objects, creating secondary light sources and shadows in the process. The vast majority of game engines don't even bother with that stuff( though apparently Nvidia is trying to change that). They just have the light hit one object and stop there. Everything else that comes after that is faked or approximated. Reflections and distortions are almost non-existent or faked, shadows are approximated, etc..."
],
"score": [
13
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fs9nlt
|
The sudden popularity of Zoom. How is it better than Hangouts, GoToMeeting or the other 100 already existing applications?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm0bdq5",
"fm0a7fg",
"fm0a2fr"
],
"text": [
"I haven't read the terms of agreement properly, but apparently Zoom is a bit notorious for not being privacy friendly.",
"I guess because you can have 12 (or 16) camera feeds on the same screen? Skype won't show more than 4.",
"Better quality, you don’t need an account to use it, only the host does. You can also screen share and customise which part of the screen you want to share."
],
"score": [
3,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fsd5wu
|
How does an SD card become write protected when you slide the little switch down on the side?
|
How does moving the little switch on the side of an SD card write protect it when accessing it from a computer?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm0t978"
],
"text": [
"This was also done with floppy disks, music cassettes and VHS cassettes, and they made it work the same way on SD cards as they did on those older media: depending on the position of the switch, it either trips or doesn't trip a little microswitch inside the card reader, telling the card reader whether it's allowed to write to the card or not."
],
"score": [
24
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fsfkcn
|
What is the difference between a search engine and a web browser? Please provide an example of both
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm12se3"
],
"text": [
"This is the equivalent of asking \"What's the difference between a Mazda Miata and a can of tuna?\" A search engine (Bing, Google, Yahoo) is a service that collates and indexes millions of web pages and the links between them, so that when you enter a search term, it can show you what you want. A web browser (Chrome, Firefox, Internet Explorer) is a program that interprets and displays web pages."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fsfncn
|
How do live traffic maps work, and how was this technology developed?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm13i70"
],
"text": [
"Pretty much anybody who is using google maps has agreed to share their location data with google. So they are able to see where you are, how fast you are moving, and how many others are near you. They use this to give you alerts to slowdowns, accidents, and other obstacles."
],
"score": [
13
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fslpiq
|
What causes that buzz sound when a mic is close to it's speaker?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm243lk"
],
"text": [
"The sound coming out of the speakers is fed back into the microphone, then out of the speakers again and so on."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fsm6yw
|
From Telephone Wires to Cell Phone Signals
|
ELI5: this might belong somewhere more like r/nostupidquestions, but how do landline phone signals get converted into wireless signals (in other words, how do landlines call cell phones)? Is that just another thing that cell towers do; like, do they just have landlines running into them and they convert the signals to wireless there?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm2a3s7"
],
"text": [
"Voice calls from a landline seem analogue and old, but behind the scenes they're all digital now. In the phone company's Central Office their hardware is converting your call into something compatible with, say, an office desk phone that uses a LAN port for its connection. Something like 20 to 50 customers might be on a single device that has 20 to 50 phone lines going in, and a network connection going out. Your call will be delivered to the cell tower as data as well, probably using the same feed that gives it Internet access for your data plan. The digital data will make it to your phone where its CPU and speakers/microphone are responsible for its side of the call."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fso3df
|
Why is out cheaper in nearly all cases to buy a new printer than to buy a refill ink cartridge?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm2i5zk",
"fm2k9re",
"fm2mxuy"
],
"text": [
"Just look at some documentaries or search on google and you’ll find the truth about why these inkt cartridges are so expensive. Its basically how companies make money. Its a total scam.",
"HP got in trouble at one point because their printers and cartridges were designed to pretend to be empty after a certain amount of time. They would read that they were empty and the printer would refuse to print but there could be half a cartridge of ink in there.",
"Because this is how the companies make their money. They charge low prices for the actual electronics, making little or no profit, because that's the price you look at. Once you've decided on the primary item, most people don't think about the cost of secondary items. How many times have you walked into electronics store to buy a printer but first looked at the price of ink cartridges, cables, or paper? A very few people have started to do that now, but no one was doing it when consumer printers first came out. When you are shopping and deciding what you can afford, you usually only look at the main product. You see a printer for $40 and think \"yeah I can afford $40\", but then they charge you another $40 for the ink, plus $15 for a $5 cable and 12 bucks for a $3 ream of paper. The store makes virtually no profit on the printer, but they make a $35 profit on the ink, a $10 profit on the cable, and an $8 profit on the paper. Not to mention the fact that you'll have to keep coming in and buying ink over and over again. This is kind of like when you buy a car and negotiate a price, but then they want to charge you $500 for undercoating or $300 for fabric floor mats. It's all part of the game to trick you into paying more than you intended."
],
"score": [
6,
6,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fspkug
|
How do artists "scan" their drawings so they look completely flawless digitally?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm2s9do",
"fm2wlyi"
],
"text": [
"Yes. Most of them have specialized scanners that allow them to accurately upload these pieces. Additionally, it helps for digital touch ups which can be a bit more versatile with some programs.",
"Scanners bigger than 11\"x17\" are rare and expensive so artists usually use photography for something this big. There are special rigs and [tripods]( URL_0 ) for photographing large flat art. The image lays flat on a bed and the camera is mounted parallel to the art on an arm that can move in three directions. Art can also be photographed hanging on a wall. Art schools typically have studio lighting and photography classes where students learn to do this stuff themselves."
],
"score": [
6,
3
],
"text_urls": [
[],
[
"https://tripodyssey.com/best-tripods-for-overhead-shots/"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
fsrxxl
|
How does a universal remote work?
|
How do they build one remote that works with lots of electronic devices?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm34j4y"
],
"text": [
"each manufacturer uses their own frequencies for various buttons on the remote. a universal remote is programmable, so you have to program each button. but most smart universal remotes come preprogrammed for various manufacturers."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
fssqwh
|
Why is it almost impossible to “decompile” executable (.exe) files to reveal the package contents?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm3bczs",
"fm3q4em",
"fm3b4uc"
],
"text": [
"Executable files are made of machine code, which is translated (assembled) from a family of programming languages called assembly. It is (usually) possible to reverse the process (disassembling) and get the same assembly code back, because the assembling process is (usually) lossless. Assembly code and machine code are very simple (relatively speaking) - there are no variables beyond a set of registers that are used and reused throughout the program for various purposes, and access to main memory. Most programs are not written in assembly code. Instead, they are written in higher-level languages that have fancy things like variables, flow control, loops, comments, and multiple files. When these programs are compiled to assembly, a lot of information in the original program is lost, like variable names, because assembly doesn't have a way of representing that information. If you want to reverse the process, you need to output that lost information elsewhere (like a file of debugging information that maps generated assembly code to the original source code), or deal with a translation with generated variable names and a very simple representation of the program logic. It's like trying to translate a sentence through a series of languages and back to the original - information is going to get lost because of differences between the languages. However, a decompiled program should still have the same function as the compiled executable, since programming languages aren't subject to as many nuances as human languages.",
"Computers speak in Machine Code. Humans suck at Machine Code, so we created Programming Language. Programming Language comes with a lot of nice features that make it easier for us to read and write it. But those aren't necessary for a computer. So when we translate from Programming Language to Machine Code, a lot of the information in our Programming Language code is lost forever, because it simply isn't necessary for Machine Code. If you try to translate in the opposite direction, from Machine Code to Programming Language, it is impossible to get the same thing that you started with. The information that made our Programming Language code easy to read is just gone! Lets do a quick example. In Programming Language, we write this: > We have 0 `apples`. > We get 5 more `apples`. > Tell us how many `apples` we have. Translating into Machine Language, we get something that might look like this: set a to 0 set a to a + 5 return a Handy. But, if you try to translate in reverse (decompiling), how can you possibly get back what you started with? After all, if you try to reverse it, you might get back something like this: > We have `a`. > Set `a` to 0. > Set `a` to `a` + 5. > Tell us `a`. That looks very different from what we started with. We don't know that `a` used to be `apples`, and the Programming Language code doesn't flow nearly as nicely as what we started with, despite it doing the exact same thing. What you end up getting isn't really that much better than the machine code you started with, and how could it? We purposefully threw away the information that makes it easy to read.",
"How easy it is depends on the program and what was used to create it. For example, old Minecraft in Java used to be reasonably easy to decompile, because the Java language is like that. However, to prevent plagiarism/piracy, the developer obfuscated the code - so instead of seeing \"class Pig has attributes movement, life, texture\" you'd just see a bunch of \"class A has attributes a,b,c\" so it used to be an effort to mod or change it. Some programs go to even greater lengths to obfuscate their code/binaries - games by Zachtronics are a rare example where sometimes they even get identifies as suspicious viruses. 'Low level' or well-optimised programs might reduce themselves so well that decompilation in a readable format is extremely difficult. A lot of programs these days are also an exe that reads encrypted .dat files (video games reading level data, for example), so decompiling the exe by itself won't get you useful information. And just in general, for complex programs, analysing them automatically can be hard! A famous computer science problem is the \"halting state\" problem - it's actually impossible (mostly) to make a program that will automatically tell you if *another* program will run forever, or eventually quit."
],
"score": [
26,
9,
8
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
fst5ol
|
In the world of video games, how do "engines" (Unreal, Unity, etc.) actually work?
|
I have a friend who works in video game design, and I am very into video games myself, but I have 0 idea how the coding of games actually works. I understand that publishers work with studios who use engines, but how do engines themselves actually work? is it through coding language, something more complicated, or something simpler?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm3fmyh",
"fm3obye",
"fm3guf5",
"fm3w0s6",
"fm4alwp"
],
"text": [
"Engines like those typically have the foundation in their code to already do what you need them to do such as terrain formation, models for bodies, water, objects, movement, etc. instead of having to start from scratch and code all those different parts yourself, you just use the engines’ framework to build your game from those assets instead",
"Yes, game engines are written with a coding language (usually C++), just like any other piece of software. A game engine is just a framework for making a game that already has a lot of the functionality a typical game needs. They can draw 3D models to the screen, they can place objects in the game world, simulate physics, play sounds, etc. It will have some sort of API (Application Programmer's Interface) which allows developers to write code to use within the engine and customise the engine's features. They usually come with a level editor and other software for authoring game content. Which can also be customised by the game developers. You don't need to use an existing engine to make a game. Maybe if you're making a simple 2D game it's not necessary. But if you don't use an engine it means you have to write all the functionality you need from scratch (or piece together existing code that does each of those things).",
"My understanding is that these engines define the “laws of physics” for those worlds, and also how graphics are depicted. For example, I remember that Battlefield: Bad Company 2 was groundbreaking because the engine (Frostbite IIRC) allowed destructible terrain. So the engine allowed things to change. The Bethesda game engines always focused on big open worlds and made it modular. So you could define the classes of things and get the framework with them. If an item was of class:ingestible, you could eat it. It made it super easy to mod. Behind the scenes, all the code defines what ingestibles are, how they interact with other objects etc. I’m no expert but this is what I’ve learned just reading articles and the developer commentaries.",
"Imagine you want to draw a box with a pencil but you have no idea how. You now need to learn how to do that in order to do it. Or: You could strap yourself into a Matrix chair and have that skill uploaded into your brain. The skill to draw a box could be one component of a game engine. It's basically a bunch of pre-written programs that ease the process of creating games by trying to encompass all possible use cases.",
"So, there are a lot of things *most* games will have in common. Most of them have some sort of a graphics pipeline to draw what is in front of the \"camera\" on to the screen. Most of them are based on similar design patterns. Most of them will need some sort of collision detection so things can bump in to each other. A lot of them have 3D lighting, 3D games tend to have physics, and so on and so forth. An engine is a framework that does all of that for you out of the box, so that you don't have to code all these things yourself. You get a nice comfortable package that allows you to focus on making what you actually wanted to make: a game."
],
"score": [
24,
11,
8,
4,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ft69zv
|
How did (or does) "stealing cable" work?
|
How did (or does) steal cable television work? In old TV series you can sometimes see people climbing and handling in the power pole in front of their house, what exactly are they doing there?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm582dx"
],
"text": [
"Cable television is literally television transmitted through electrical cables, rather than over radio. The cable ran across the city, just like electrical cables and phone cables. When you signed up for cable, a technician would put down a cable from these cables to your home. Stealing cable is just connecting to these cables without permission."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
ft9064
|
When rebooting a PC, how does it know to turn back on again after turning off.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm5piw8",
"fm5pl5t"
],
"text": [
"On a restart one of the last things done is there's an ACPI (Advanced Configuration and Power Interface) command sent to the BIOS to get the machine on switch off to boot itself back up. It's as simple as that really. The 'on' signal on a modern computer is just a soft button press. The motherboard always has a bit of baseline power as long as the power supply has power connected to it, so it's possible for the computer to send the signal itself to start the machine back up.",
"A \"reboot\" normally does not actually turn off the PC. More like it sends a signal to everything to clear out a bunch of stored memory and put them back to power-on defaults. This includes some parts of the CPU that make it start running the BIOS/firmware again like it was just turned on even though there was no power interruption. It only acts like it lost power. But even when a computer is off, there's still power. The power supply still gives a couple of volts on a small number of wires all the time even when it's off, just at a much lower capacity. That is enough power to keep the data in RAM if the system is just in stand-by, and to power a weak CPU which can signal a power-up when the time comes. You can configure a PC to power on at a certain time of day, or when a signal arrives on the network, or a couple of other things and it will do it. When signalled the power supply will bring up full voltage on all wires and the PC turns on or wakes up. There are types of reboots that do power the system off, and basically use that automatic power-on feature to turn itself on a few seconds later. There are some types of security features which turning them on or off may require cutting power to the CPU, in which case this will happen. But this is the exception to the rule."
],
"score": [
13,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ftbmm2
|
We’ve teleported particles a few years ago, how does that work?
|
Just seen this thing by Brian Cox and already a few years ago, we teleported a single particle from one place to the other which gets me very confused Firstly..... how? And secondly, how would the particle of appeared? How did it displace the air particles? If the particle popped into existence in the other location, wouldn’t it prove the Big Bang theory is correct? As something came from nothing Sorry for my confusion lol
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm66gp1",
"fm6g6ew"
],
"text": [
"I really wish they hadn't used the word \"teleportation.\" It's not teleportation in the sense that you're thinking, it's more akin to instant *communication*: i.e., transmitting information instantaneously (although it's not really that either, for reasons that get... tricky to explain). Basically, they're talking quantum entanglement. Even if it had been actual teleportation in the traditional sense, this wouldn't have violated the conservation of matter and energy, as it'd just be moving it from one place to another instead of creating or destroying it. And even if it had been creating or destroying matter, that wouldn't really have told us anything about the Big Bang because that didn't involve matter and energy being created, it involved space itself expanding very rapidly.",
"If you mean the quantum teleportation experiments in 2016 and 2018, we didn't teleport anything physical. As was said before, \"teleportation\" was a seriously bad choice of words. Quantum teleportation is a term coined to reflect a much more understandable - although still extremely cool - phenomenon called *quantum entanglement*. Two particles sharing the same quantum state (which can be achieved in a few ways) can be separated by large distances yet each reflects the state of the other. That sounds a little weird, so let's simplify things. Assume you have two light bulbs. Because of how they were made, each bulb does exactly what the other one does. We'll put one in London and the other in Sydney. Even though they're separated by about half a planet, they still behave the same way. If the light in London is lit, then the one in Sydney will be lit. The effect works in both directions, and no matter what, those bulbs stay in sync. All that's being \"teleported\" is the state of the bulbs, not the actual bulbs themselves. Naturally, since we're talking about quantum spin states of particles, it's a lot more complicated than on/off, but that's the basic idea."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ftdg4o
|
What causes bugs/glitches in video games?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm6kgde",
"fm6gbs7"
],
"text": [
"Bugs and programming are inseparable. Where you have code, bugs will appear. Whether they stay there, however, is about being careful and responsible. Basically, a bug is usually a typo. Using the wrong name of a variable or function, the wrong symbol, not closing a parenthesis, even missing a semicolon will throw things into chaos. Now, many of these bugs are caught during a process called *compiling*, where the code the programmer has written is translated into instructions the computer can actually execute. During compilation, the compiler catches the simplest bugs because they can't actually be converted into working instructions; the compiler lists these errors out and the programmer can go back, fix them, and try again. This happens constantly in programming. However, some bugs make it through to the actual program. How? Because they don't actually break the instructions, but they don't work the way they're supposed to. A function might not be called when it's needed, making the program behave incorrectly. A great example is *Aliens: Colonial Marines*, a game released in 2013 by Gearbox Software. The AI running the aliens in the game was intended to constantly operate and keep the hostile aliens within a set distance of the player, ensuring that the player had to stay constantly alert and be ready to defend against them. However, when the game came out and people started to play it, they realized something was very wrong: the AI often did nothing at all, even when the player was standing right in front of an alien. Definitely a bug. After some digging, someone figured out what had gone wrong. The AI activity system, called \"tethering,\" was a function called as part of the AI routine. However, a programmer had screwed up and instead of typing \"TETHER\" actually wrote \"TEATHER\" into the code. The program attempted to call the \"teather\" function - which didn't exist - and never called the \"tether\" function. The AI never got a chance to do anything because it was never asked to. This is why code testing is so important. Running a program through a lot of operations, making sure it behaves correctly no matter what the user does, is a key element of software development. Unfortunately, this takes time and money, so companies don't generally invest much in testing anymore, preferring instead to release their products and issue patches and hotfixes to correct bugs identified by the public.",
"Videogames are complex and often function on the very edge of what the computer can handle. As such, even a small mistake can have some really interesting results. There are also late-development optimizations that developers do, and those optimizations tend to make it harder to test their code thoroughly. Thus, sometimes things can slip through."
],
"score": [
15,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ftibmu
|
What causes websites to crash after sudden, consistent high traffic and how are they fixed?
|
If a website encounters an influx of unexpected traffic for multiple weeks causing it to crash, how do they fix this and how long would it normally take? Also, how could it still not function during lower traffic times?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm7aasm",
"fm7cslh"
],
"text": [
"Websites are hosted by something called a Web server and the people connecting to it are called web clients. Imagine a drive through restaruant, let's call it McRolands, serves people that arrive in cars one by one. Each car places its order (requests a web page), McRoland cooks the webpage and gives it to the client. It can handle the normal amount of traffic coming to it fine. Now imagine all of a sudden a bunch of coaches turn up with 80 people on board. It's got to serve all them tasty web pages to the people on the coaches while the usual amount of traffic is still coming to the restaurant. There's a big hold up, people can't get their BigWebs and WebShakes. McRoland has a big back order of requests that it needs to serve and people aren't getting their stuff. Annoyed, some of the people drive off because they can't get their stuff. Meanwhile McRoland might still be trying to process those requests so it's still trying to serve up a Royale with Java, walking round the car park trying to find some one who's already left. Sometimes the server will eventually catch up as the timeouts expire on the requests and they start throwing uncollected orders in the bin. Sometimes it may just crash the whole system and requires the Area Manager to step in and turn the restaurant off and on again.",
"When a page is being loaded up there's a worker (thread) on your computer that makes a (tcp) connection and sends a request for the page. On the internet somewhere there's another computer that has the page and it also assigns a worker (thread) just for you. This is a point of choking while milions can access a single site, that computer gets overloaded creating miliins of programs (one per client) to handle them. This is mitigated by having multiple computers in the same room or building and distributing the clients. Then there's the information overload, sometimes the page isn't as simple and it needs to ask for some detail from some book (database). If too many people in the room fight over the single book that holds the data then it also locks up and you get weird traffic jam effects. Then there's what's called a dns overload. When you first type in a name in your browser your computer has to check that name against an address to find it's computer destination that is the country/town where the server is. It used to happen when too many people in an area went to the same \"phone book\" to search for an ip/adress it would lock that up and your computer couldn't load a page it hasn't seen before. Hope this clears it up, there are even more limits and scenarios around traffic routing, but in all cases you can imagine it as car traffic jams in cities or highway intersections."
],
"score": [
31,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ftm5qk
|
How exactly does a computer transcribe interviews - what enables the audio to text conversion?
|
Title is pretty self explanatory.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm7yuq6",
"fm8633y"
],
"text": [
"We've gotten very good (through AI learning, and having humans manually translate) at teaching computers what sounds translate to what words. It's gotten good enough that computers can now translate on the fly. Try enabling closed captioning in your next google hangout to see it in action. The computer knows what sound mean what words, and then passes through a couple of other filters to provide context and make it even more accurate.",
"The computer has a massive library of spoken words and text so it has a general idea of what a particular word is supposed to sound like. It will take a recorded bit of audio and look at how closely it matches other audio samples in its library. Based on that it will make a best guess at what the word is, but it's not always accurate. Just to be clear, the computer isn't actually matching your speech with a giant library of sounds. It effectively takes a bunch of speech saying the same word and creates a math formula that will take your speech and give a % chance that it is a match. It will then use that % chance to make a best guess at what you're saying. I'm glossing over a lot of details here, but this is the essence of machine learning and why companies like Amazon and Google are so interested in recording your conversations and gathering data on you. They use it to train computers to do things like this."
],
"score": [
7,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
fto7v1
|
How can a 15+ year old movie be resold as a 4K title today?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm81r2j",
"fm82if7"
],
"text": [
"35mm film stock has a resolution of about 4k (or a little more) so old films can be copied digitally in 4k if a good quality film copy of them still exists.",
"It is only recently that 4K **digital** film technology have been used to make movies. However 4K quality **film** have been available since the beginning. Instead of carefully constructing each tiny little pixel in a CCD that we do today they used chemical processes to make a random pattern of equally tiny photosensitive crystals grains on a strip of film. So in order to release them in 4K today they would just have to scan the film again with a high quality scanner."
],
"score": [
7,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ftprny
|
how do video games get created and still have secrets years after their creation?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"fm8bty6"
],
"text": [
"Game files can be hacked but what matters is if is found can be deciphered. At the end of the day, it's all lines of code and if that code isn't clearly labelled or its function isn't easy to understand, then it might be hard to determine what it is. If hackers find a line of code labeled \"Easter_eggs_secrets\" then they will find out what it is pretty quickly. If it's labeled \"function_x1_object\", what is that? What does it do? Is it worth finding out?"
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
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