q_id
stringlengths 6
6
| title
stringlengths 4
294
| selftext
stringlengths 0
2.48k
| category
stringclasses 1
value | subreddit
stringclasses 1
value | answers
dict | title_urls
sequencelengths 1
1
| selftext_urls
sequencelengths 1
1
|
|---|---|---|---|---|---|---|---|
ik6nhe | Why haven’t we made camera lenses that replicate what the human eye sees? | Technology | explainlikeimfive | {
"a_id": [
"g3imct5",
"g3ilzyc",
"g3iuk63"
],
"text": [
"So the human eye would take incredibly terrible pictures. You have a tiny area which is in focus. As you read a sentence, your eye moves from word to word to word as you read. If you try to focus on one word and then look at something on the opposite side of the screen, you'll notice that it's extremely blurry. This is not super noticeable in daily life because your eyes are always moving to what you're looking at, so you don't notice that 99% of what you're seeing is out of focus.",
"We ... did .... a modern camera is very similar to out eyes. Both have a lense, both have a shutter. The lense of a camera is even better than the lense of the eye. The only difference is, that hour retina is more sensitive than a CCD, because compared to a CCD or CMOS chip, it has much more receptors per area than the chips have pixels per area.",
"Your eyes and brain don’t even see everything in your actual field of view - a camera that works like our eyes would be blurry in an oval/sphere around whatever it is focusing on as our eyes do that. Your eyes also don’t *see* what is between point a and point b when you look from one to the other. That’s too much information and you don’t need that so your brain and eyes aren’t actually detecting everything they can see unless **you** direct your focus to them. Try to think of everything you directly looked at today - you already won’t be able to do that so imagine what your memory or thinking box looks like if you are also remembering everything in between the things you looked at? Your brains SD card ain’t got that kinda space lol. A camera like our eyes would suck eggs lol"
],
"score": [
13,
3,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ik7a1l | Why does most software take a bit of time to start up, but can quit almost instantly? | Technology | explainlikeimfive | {
"a_id": [
"g3isod2"
],
"text": [
"Because there are lot of allowable states for the computer to be in that conform to \"the program isn't running,\" but only a few that conform to \"the program is-yes running.\" If we imagine computers with an industrial-site metaphor, starting up a program consists of (a) finding a suitable building plot (b) demolishing whatever was there before (c) building the new factory and (d) putting a sign out front that says \"Now Open!\" (In reality, most computers do steps b and c in one operation, but let's just roll with it.) But quitting a program only requires one step: taking down the \"Open\" sign. (Okay, there's another, related step: informing that site office that you're done with the plot and someone else can come along and demolish your building if they want.)"
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ik8dx9 | Why do current gen systems (Xbox one, PS4) have to download physical copies of games before we can play them? | On older systems you use to just be able to put a new game disc in and play it right away? What is about the current generation that doesn’t allow this feature and requires game discs to be downloaded onto the system before they are able to be played? | Technology | explainlikeimfive | {
"a_id": [
"g3ixsdp",
"g3iy04r"
],
"text": [
"One main reason: the file size of games have increased to fit higher resolution textures/cutscenes/models/etc, but optical drive read speeds haven't changed drastically since Blu-ray was first introduced. To avoid having to pause the game to load content, it's preferable to have a lot of the game files stored on some faster storage media.",
"Optical drives are slow compared to a hard disk, and modern games contain massive amounts of data. Even now, games suffer from long load times due to having to transfer a lot of data from disk to memory. This would be even worse if it was loading directly from the blu-ray."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
ik8lge | if you are ip banned from a website and then have your ip changed then what stops someone being assigned your old ip and not having access to that website? | Technology | explainlikeimfive | {
"a_id": [
"g3iz8lb",
"g3izlng",
"g3j0lch",
"g3izlx8"
],
"text": [
"if the ban is only based on the IP then nothing. if they ban a certain IP, then that IP is banned. but sometimes the ban is not IP based, but based on say some cookies or some other fingerprint you leave behind when you visit the website, or the ban may expire after sometime.",
"IP addresses are often dynamic so if you want to ban an individual user it's rarely the way to go. Some companies will ban IP ranges to reduce the impact of bots. There are other ways to identify a user including cookies and other information provided by the browser. Check out [ URL_0 ]( URL_0 ) to see how easily identifiable you are!",
"Absolutely nothing. I have been to a website that i could not acess because the IP was banned long before i had gotten there.",
"Depends on how the ip was blocked. If you’re maliciously attacking URL_0 they may block your ip and if someone were to get that ip later they would probably be unable to access Reddit However if Reddit legally gets the isp involved they could some more advanced blocking that would be tied to more than your ip"
],
"score": [
13,
9,
4,
4
],
"text_urls": [
[],
[
"https://amiunique.org/"
],
[],
[
"Reddit.com"
]
]
} | [
"url"
] | [
"url"
] |
|
ik8p6u | How do snipers with side mounted scopes work? How does the scope line up to where the bullet fire if the scopes a few inches away from the barrel?? | Technology | explainlikeimfive | {
"a_id": [
"g3j09iw",
"g3j2htf"
],
"text": [
"in World war 2 you have a spitfire with 8 machine guns on it, those machine guns would have a convergent set, the convergence is where they would meet (the set distance Infront of the plane where all guns were pointed) now when you setting up your scope you would always set range for a certain distance and have it hit at that point or you would take into account that your aimpoint is 1 1/2 in down to the right",
"It's just a slight offset. You just zero it so your cross hair is offset a certain distance from the bullet impact. Same as a lasers being used."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ik8qcl | how do infrared cameras work? Why can they see infrared light but we cant? What’s different in the lens of a camera to the lens in our eye? | Technology | explainlikeimfive | {
"a_id": [
"g3j0cyf"
],
"text": [
"Infrared cameras have little pixel sensors to detect infrared light, as opposed to visible light in a normal camera. The lens works similarly, but traditional lens glass absorbs IR light and so a special glass must be used. Our eyes have four different kinds of cells for detecting light. These cells use chemical reactions that detect specific frequency ranges of light. When a normal camera is made, we try to give it three sensors to mimic the three cells/frequency ranges in our eyes that detect color. Thermal IR is beyond the range of what eye chemicals can detect, and so we can't see it."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ik9fw2 | what are bots exactly? | Technology | explainlikeimfive | {
"a_id": [
"g3j502z",
"g3jps3k"
],
"text": [
"Like call bots, email bots, text bots or just robots? Can you give a scene?",
"A bot is a piece of software designed to automate the tasks that would normally be performed by a human. What the bot does, how it works, and whether it's acting maliciously or not, are going to depend on who wrote that software and why."
],
"score": [
8,
6
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ik9wjc | why do some US plugs not fit then you turn them and they fit? | Technology | explainlikeimfive | {
"a_id": [
"g3j8o39"
],
"text": [
"on some two prong US plugs, one prong is wider than the other. This is for devices where polarity matters. AC power comes on two lines, one 'hot' and one neutral. Many devices can handle this either way, they just care about the difference between the two. some care which is which, so they have their prongs one big and one small to make sure you connect the right side"
],
"score": [
17
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ika75l | How did Victorian scientists test for chemicals/substances in blood before the age of modern technology? | Technology | explainlikeimfive | {
"a_id": [
"g3jchki"
],
"text": [
"Even at the Victorian era the knowledge base for chemistry is not too different from today. Many modern chemical principles were theorised and proven back then. There are simple chemical tests that were known at the time. There’s a famous case study of this where a person who died of what was suspected of arsenic poisoning. Instead of testing post mortem blood like we would today, they boiled the stomach of the poisoned, extracted the broth, and removed any other organic matter with nitric acid. They can then test the resultant dead person stomach soup for arsenic. It was rudimentary but it worked. Source: The Secret Poisoner: A Century of Murder"
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ikb8vk | What is "ping" and why is it bad when the number is high? | Technology | explainlikeimfive | {
"a_id": [
"g3ji91f",
"g3jm3md",
"g3jipsf"
],
"text": [
"A ping is how long it takes to send and receive data. The higher the number the longer it takes a piece of information to go from point a to b and back.",
"I see a lot of people explaining ping, but I want to just step in to present an analogy. You want your computer to load a website. Pretend instead you want an apple from the grocery store, and you have an assistant that can go get it for you. Ping is how long it takes your assistant (computer) to go to the grocery store and get the apple (website) and bring it back to you (you). When you want an apple, the quicker the better. The biggest difference is that ping is measured in milliseconds.",
"Ping is the amount of time, measured in milliseconds, that it takes for one device (like a computer) to send and receive data from another device. Usually used in video games so you can get an idea of how healthy your connection is to the game server. A lower number = a faster connection, which means the server can receive your commands faster and then calculate what that means and then return to your computer the results of that input. A higher number = a slower connection to the server. This is bad because it can make it hard for the server to take your commands and calculate that with the other commands from the other players. It's how you wind up with \"rubberbanding\" (when you are trying to move forward but you keep getting set back several steps), your shots don't get registered before your opponent's shots so you end up dying even if you saw them first, or your shots miss because you're aiming at an enemy's position when they've already moved on."
],
"score": [
18,
11,
7
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ikbxd3 | How does the computer understand if the binary value stands for an alphabet or a number? | So computers represent everything in binary and for alphabets most use the ASCII system, right? Well, how does the computer know if I typed in an alphabet or a number as they can stand for both? for example, 1000001 in binary can be the number 65 or A. How can a text processing software differentiate? I tried googling the same and all I got was how ASCII was just a human convention and whatnot. | Technology | explainlikeimfive | {
"a_id": [
"g3jo1fv",
"g3jpn42"
],
"text": [
"If it is a very basic text processing software, it will assume anything it processes as data is ASCII (or possibly Unicode). The more general answer is, it is the software and how it is written. Most sophisticated software doesn't process data \"raw\", in the sense that the information is usually packaged in data structures that contain a lot of contextual information regarding that data. This contextual information may identify the data as a number (many different types of numbers - integer, floating point, large integer etc) or a color code or a character (or string of characters) or a command character etc etc.",
"Truth is it doesn't really. Programmers just write it to try to prevent the mix up from happening. Often it's something the people who made program making tools wrote. The compilers will complain if they mix it up, but languages like C let you play fast and loose and let you recast a letter as a number or whatever. It so bad that computers can’t actually tell the difference between a letter, number, but most importantly, an instruction of what the computer should do next. Several hacks and exploits were made by writing in the stuff corresponding to a cpu/hardware instruction into a place where you were only supposed to write in text. The computer would keep writing past the part where it was supposed to be text, and start over writing instructions on what to do next. This is called a buffer overflow vulnerability."
],
"score": [
7,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
ikdxfu | Why are grill lines darker than the rest of the food but toast made in a toaster oven has lines lighter than the rest of the toast? | Technology | explainlikeimfive | {
"a_id": [
"g3k0kbp",
"g3k0ox3"
],
"text": [
"Because in a toaster the lines you see are from the bracket which holds the bread in place and blocks direct heat from the heating elements behind them.",
"Because in the toaster the bread is really touching the metal a whole lot, and the very hot heating element is super close to the bread, giving it an even toast. On a grill, the metal bars of the grill are getting heated super hot, and on top of that the full weight of whatever meat your cooking is resting on those grill bars, leering it really cook/burn the lines into the meat."
],
"score": [
13,
4
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ikhzh8 | - How do authorities check if you're watching TV without a licence in the UK? | Technology | explainlikeimfive | {
"a_id": [
"g3krz57",
"g3knqrj",
"g3kmyyd"
],
"text": [
"You need a license to watch TV in the UK?",
"Seems thus far they have been rather secretive about how and if the technology works well. One cool thing they claim to be able to do is they can use light detectors to scan a household. If the household is watching a TV station, the brightness of the lights from the window will change as the TV changes, and this can be mapped to the brightness of the current broadcast, if it matches then one can know that TV is being watched in there. [There is also an entire Wikipedia page on this topic. Seems thousands are prosecuted for it per year, which is pretty surprising given how hard this is to catch.]( URL_0 )",
"Years ago they used to drive vans around that would be able to detect which houses were and which houses weren’t.. but now I think they just send letters to every house that doesn’t have a TV license, and expect people to buy one. I too would love to know this."
],
"score": [
19,
7,
3
],
"text_urls": [
[],
[
"https://en.wikipedia.org/wiki/Television_licensing_in_the_United_Kingdom#Licence_fee_enforcement"
],
[]
]
} | [
"url"
] | [
"url"
] |
|
ikk7hm | How do deep-fakes work? | Technology | explainlikeimfive | {
"a_id": [
"g3lqegx",
"g3l2ou7",
"g3lcig2"
],
"text": [
"A deepfake exploits two machine learning models. One creates the forgeries from a data set of sample videos, while the other tries to detect if the video is indeed a fraud. When the second model can no longer tell if the video is fake, then the deepfake is probably believable enough to a human viewer. This is called generative adversarial network (GAN). If you're interested you can learn more about it in [this definition]( URL_0 ). It explains GANs in simple terms.",
"Deepfake technology can create a digital face mask of person A with data from photos or videos and then using powerful algorithms, overlay that precisely on a video of person B, adjusting view angle and matching facial expressions by morphing the mask. It takes a lot of computer processing power to do this frame by frame on high quality video but is I think already possible in real time.",
"Deepfakes use an algorithm that is able to take two faces and figure out the parts of face A that match to the parts of face B. Because faces are 3D (and can have lots of different expressions) we need a huge amount of images of both faces to give the algorithm enough information to work with. Once you've given it enough source information from both faces, you can give it a video of one of the faces and it can very closely map the other face onto that video. Where it falls down is when the video you're mapping to has facial expressions/angles that weren't represented in the training data, the algorithm tries its best in that case, but it will look weird to humans, as we are very very good at recognizing faces."
],
"score": [
6,
4,
4
],
"text_urls": [
[
"https://www.techslang.com/definition/what-is-a-generative-adversarial-network-gan/"
],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ikk7z5 | How does autotune work? | If you change the frequency up, you need to squish the audio, but when you autotune it, it doesnt sound faster or slower. Same when it pitches down. How does it fill the gaps and make it sound good? Is it the same when using different speeds on youtube? The sound doesnt pitch up or down when you make the speed faster but it is twice as fast. | Technology | explainlikeimfive | {
"a_id": [
"g3l9w06",
"g3mehib"
],
"text": [
"There is a thing called the Fourier transform which allows you to describe a wave-like structure as a mix of frequencies. So you can just encode the sound as a spectrogram (that mix of frequencies and how it changes over time), shift all the frequencies up and then use the inverse Fourier transform to produce the sound from this new pitched-up spectrogram. You'd lose some data this way because the sound is encoded in a discrete way and the calculated spectrogram has to be finite and discrete as well (because we have to store it in the device), but if you do it carefully, the distortion will be small enough.",
"I have some experience with FL's NewTone, which is a similar program to Autotune. It uses a Fourier Transform (which is just some complicated math) to chop the audio into several discrete \"fingerprints\" (my terminology), each representing a particular timbre and pitch. In other words, at each point in time, what vowel or consonant sound is being played and what note is it? Pitch shifting is done by changing these individual \"fingerprints\". When it plays back, it takes these fingerprints and connects them to make it sound like a continuous sound again. You can also move the playhead around and play these \"fingerprints\" forwards or backwards at any speed you want. The program will do the math to connect the individual fingerprints into one continuous sound. You can even stick on one point in time and just play that vowel sound forever if you want. The further you go from regular playback though, the more robotic it sounds. You're not really playing the original waveform at any time, you're reconstructing a new waveform that sounds very similar to the original one. There are many ways to do this time stretch, by the way. This is just one of many, and the algorithms are continuously being refined to sound a little more natural with each new version."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
ikn3gj | How are graphics cards "specialized" to do calculations over a CPU? | Technology | explainlikeimfive | {
"a_id": [
"g3lxcyn"
],
"text": [
"I have a friend who used to work for ATI. He said look, all the circuitry on your CPU to perform mathematical computation takes up a very tiny corner of the whole silicon wafer. The CPU is actually very good at branching instructions, IF... THEN... ELSE... The GPU, a wafer effectively the same size as your CPU, uses almost the entire wafer *just* for multiplication. Not only can it do it faster, but it can do more of it at once. In video games, there's a lot of multiplication for all that geometry."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
iknv78 | Is there a technical (non-monetary) explanation for why a game console like the PS5 wouldn't be backwards compatible with all PS4 games? | Every year a new console launches, only supporting a handful of games from the previous generation. I always assumed this was for monetary exploitation, and to not demolish the sales of the previous console on the pre-owned market. But I'm also interested in knowing if there's an actual technical limitation behind this decision. | Technology | explainlikeimfive | {
"a_id": [
"g3lzft7",
"g3lyvfv",
"g3lzdoa",
"g3m0dtv",
"g3lzqkw",
"g3m5oqv",
"g3lzvog",
"g3m0o77"
],
"text": [
"Unlike PC games, console games can be really tightly integrated and optimized with the console hardware because the game authors know \\*exactly\\* what hardware they're going to run on. This is part of why a console can pull off more intensive games than a computer with equivalently powerful hardware. But...this means that the game is written assuming all that hardware is available. The whole point of a new console is to give the developers new, more powerful, more capable hardware to write their games on. To make a PS4 game run on a PS5 you have to include an extra \"layer\" in the PS5 to translate for the PS4 game. The PS4 game doesn't know it's on a PS5 and it expects PS4 hardware; the PS5 needs to handle those requests and make the fact that it's a PS5 invisible to the PS4 game. This means, at bare minimum, a bunch of extra software to write & test. If there was a format change or specific hardware functionality that isn't used at all on the PS5, you might also have to install the extra hardware (and related software to run it) just to support the PS4 game. That's all doable but you have to do it as an explicit and intentional effort to run backwards compatible games, it can't just happen by accident.",
"The chipset changes from console to console. To support backwards compatibility often times the CPU in the machine no longer understands instructions the same way the last console did. In these cases you need to add emulation to your console which require either additional hardware or development time. Both of which increase cost. That’s why you frequently see compatibility only supported early in a consoles lifecycle and they often remove it later to reduce prices when the new console is more popular.",
"Unlike a PC, modern console hardware is very streamlined for the specific console. This allows them to actually get more processing power out of what is more or less the same equipment compared to a general purpose computer. If they wanted the PS5 to support PS4 games, they would either have to have a second set of hardware in there to run PS4 games, as they have in the past with backwards compatibility, or to use Software Emulation to run a virtual PS4 on PS5 hardware. Software emulation has a huge performance penalty, so it isn't really feasible.",
"The answers so far kind of hit the point, but it's more than hardware, it's also software. MS has worked hard to keep the basic engine used for all their Xboxes similar, which makes backwards compatibility simple, even with changing hardware. Sony did not do this. With each new console, Sony utilized a different engine, which makes backwards compatible much more difficult. The PS4 and PS5 supposedly are designed similarly, which makes backwards compatibility simpler, but the PS3, PS2 and PS1 are all different, which means sony either has to go with software emulation which is definitely resource intensive, or build in the hardware for the older console, much like the launch PS3s did for PS2 backwards compatibility.",
"most of the console systems up until this gen did backwards compatibility by including the actual hardware and Bios of the supported system(ie early Ps3 system versions had some of the ps2 hardware built in for backwards compatibility.) . This generally works well, but it adds up to the cost of manufacture and makes the PCB more complex(plus requires a form of coding Hook so the system can seamlessly transition between normal functionality and backwards compatible mode.). in these current Gen systems they are so much more powerful and posses similarly archs to actual PCs that there is very lil incentive to do the same, instead relying on Emulating(which is funny actually) the older hardware with their in-house tools, however since manufacturers are lazy and want the cheapest possible costs they make their emulation very barebones(resulting on poor support since all they want is to claim they support, even if said support is garbage) or rely on a 3rd party tool(that they cant support without paying so they dont.) Verdict: cheaper and greedier manufacturing and programming.",
"The PS5 should support all PS4 games in theory. But there are roughly 2800 games for the PS4 on the market; it's simply impossible to manually test each of them to make sure it also runs on the PS5. So Sony just tried out the 100 most popular titles and made sure they work well. So probably most games will work out of the box, Sony just cannot guarantee it. And while profits are of course a reason for missing compatibility now and then there are also technical reasons; the PS3 had a very unusual processor, making emulation very hard. However, the PS4 and PS5 use the same architecture, just like two different gaming PCs would, so the only thing that would prevent compatibility between them is software.",
"I remember when this issue came up during the launch of Xbox one. Console games are designed to run on a specific machine with a specific processor with a set clock speed and other known specs. They design them this way so that they can optimize the game's performance over its adaptability to other hardware. Xbox eventually came out with backwards compatibility by installing a virtual machine of the 360 and downloading owned games.",
"PS4 and PS5 both use the same CPU instruction language, X86. It should be a lot easier to emulate games unless they use PS4 specific features. This is much easier than getting PS3's highly custom CELL CPU based games to run on PS4's X86 based CPU as you lose too much power translating. It was just too different. Early PS3's actually had PS2 chips inside them to run backwards compatible games until Sony was able to emulate the PS2 via software. Xbox 360 used a PowerPC based CPU which we already have seen translated to run on X86 before like when Apple switched Mac's from PowerPC to Intel X86. So Microsoft had an easier time making 360 games run on Xbox One's X86 CPU. In a few more years I'm sure we'll have hardware powerful enough to brute-force emulate the PS3 in real time. Maybe the PS5 already can do it. Too many unknown at the moment. With all these different CPU languages I think it's less to do with money and more to do with having enough power to translate the instructions in real time."
],
"score": [
285,
35,
16,
13,
6,
5,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
ikouz6 | how do people crack games? | Technology | explainlikeimfive | {
"a_id": [
"g3m84cn",
"g3mav9m"
],
"text": [
"The game programmer wrote code that says roughly: draw_start_screen() licensed=get_license_status() if licensed==false: exit enter_game() Cracking a game involves removing that 'exit' line. Since the end user doesn't have the source code they have to look at the compiled code which is much harder. Debugging tools can help track when the game makes the license check and then that instruction can be patched over. Now of course contemporary games make this more complicated, so it is a battle of game developers making more complicated code to check the license status and people trying to disable it. Game makers might look for debugging tools and change their behavior; someone might use a VM to hide the fact a debugging tool is being used. The game might check for a debugging VM, people start hiding their VM status. It is a back-and-forth game. Nowadays game makers might put a small but critical portion of the game online such that the game only works if the remote service is available and checks the license. Then the user has to guess at that functionality and reimplement, or figure out how to patch around it. But ultimately it all comes down to the game checking on a license and taking an action, and the user tricking the game into thinking the check has passed.",
"Depends on what is being \"cracked\". Toger covered how games are cracked for pirating, but consoles are a bit different. They generally involve getting a fake update by getting the console to receive information some way that the system was not designed to resist against. & #x200B; For example, the common crack for Wiis involve a homemade update that's disguised as a Wii mail message (which are usually ads from Nintendo). Opening the message allows the update to get into the Wii and do its thing, since the original developers never thought to prevent an unauthorized update getting through that way. Once the update takes hold and rewrites the Wii software (as much as it can or is programmed to), it allows the Wii to recognize software from other means through what's basically a homemade driver. So now you can connect something like a USB flashdrive to the Wii and it'd know how to read off of it. Each console's a little different, but it's usually the same premise: Find a weakpoint, force an update in, have that update change the console to read information in ways it couldn't before. Sometimes, it's as easy as plugging in a flashdrive with a modified update, other times it's through a backdoor in the console's mail system."
],
"score": [
155,
21
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ikq8gr | How do they extract iron and other ores from rock? | Technology | explainlikeimfive | {
"a_id": [
"g3mk3il"
],
"text": [
"Usually metals are in an oxidized form in rock - e.g. not just iron, but iron oxide. Crush it into small pieces then burn with charcoal (or other carbon source), the heat unlocks/allows the oxygen to go where it \"prefers\", so the oxygen moves over to the carbon, to make carbon dioxide; leaving just iron; which melts and flows to the bottom. Aluminium is a bit special, because the oxygen much more \"prefers\" to stick to it rather than carbon (or only move a small percentage); but most common metals are all the same overall process - Adding heat frees the oxygen to move, then rip the oxygen off using carbon, turn it into metal, melt it."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
iksxaz | how do hearing aids work | explain like im five i never understood how hearing aids could give the ability to help someone hear or even give them hearing | Technology | explainlikeimfive | {
"a_id": [
"g3n5fzd",
"g3nj149"
],
"text": [
"Most of them amplify the sound and direct it into the ear canal. Essentially a microphone and a speaker. If somebody is completely deaf, they wouldn't do anything. If somebody has hearing loss, they can make the sound loud and clear enough for them to hear. Think how glasses wouldn't do anything for a blind person, but they will help someone who has poor vision. I think there are probably different types, but that is the basic principle for most of them.",
"your question was already answered, but I wanted to add that regular hearing aids don’t work for completely deaf people. there are, however, devices called [cochlear implants]( URL_0 ), which essentially record sound and translates it into electrical signals. It doesn’t give back normal hearing, since ears capture the sound differently, but with time the person learns to interpret these signals and recognize speech. edit for grammar"
],
"score": [
8,
4
],
"text_urls": [
[],
[
"https://www.mayoclinic.org/tests-procedures/cochlear-implants/about/pac-20385021"
]
]
} | [
"url"
] | [
"url"
] |
ikug3e | Why hasn't Tesla's technology for free worldwide wireless electricity been recreated? | Technology | explainlikeimfive | {
"a_id": [
"g3nfxo3",
"g3ng4bs",
"g3nk8t4"
],
"text": [
"It wasn't free. It would have required huge power stations dumping vast amounts of energy into the planet and then retrieving a tiny bit of it elsewhere, with the rest being wasted as heat. Still would have charged customers for that energy. Sounds like an awful system, especially considering the environment. However, ultimately, it relied on the Earth being able to transmit radio waves within - something it cannot do. Ergo, not only was it a bad idea, but it was downright impossible.",
"Hugely impractical and many of the assumptions Tesla based it on have proven to be inaccurate.",
"It has, but it's extremely inefficient. The vast majority of the power generated is wasted."
],
"score": [
16,
9,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ikwhe3 | Why are we trying to make transistors smaller? And how do we manufacture them to be so small (nanometers)? | Technology | explainlikeimfive | {
"a_id": [
"g3nwc71",
"g3nwjju",
"g3nwo6f"
],
"text": [
"The smaller we can make them, the faster we can make a processor work. Electricity doesn't travel instantly, it has a finite speed. In a processor it will travel through hundreds of transistors. The smaller they are, the shorter the travel time. So the faster the processor.",
"The smaller they are, the more you can fit in a chip, the more power the chip has. If you can only fit 1 transistor on a chip it only does one transistors worth of work, if they’re half as small, you can get two transistors worth of power in the same amount of space, and so on. It’s just more space efficient to have them smaller",
"Smaller means more will fit in a die so processors can have more cores. They are manufactured with lithography. It takes many steps, but essentially you put a thin coating of some material on a big wafer. Then you add a layer of \"light\" sensitive chemical. Then you expose each die with super-bright \"light\" through a lithographic screen. Then you wash away the unexposed sensitive chemical. Then you etch away the material you just applied in places where it isn't protected by the light sensitive coating. Then you dissolve the exposed light sensitive material, and start over with a thin coating of a different material. This \"light\" has to have a very short wavelength to make tiny transistors. In some processes x-ray light is used."
],
"score": [
4,
4,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ikzc3u | What algorithm does the computer use when resizing images? | When making an image bigger, the computer needs to add pixels : How does it know what pixels to add and where? On the other hand, when making it smaller, the computer needs to remove pixels : Which ones does it choose? | Technology | explainlikeimfive | {
"a_id": [
"g3onm0r"
],
"text": [
"There are a bunch of algorithms used to scale images. The simplest, nearest neighbor, just duplicate the closest pixels. This works great for things like pixel art. Bilinear basically interpolates a linear gradient between pixels. So a hard edge between black and white would become a smooth transition of black to gray to white. There are also some more complicated algorithms that will try and guess the shapes/edges and preserve them."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
il2ksr | Many apps ask you to buy an ads-free version for a couple dollars. Do they actually make more from this $2 sale than from displaying ads? | Technology | explainlikeimfive | {
"a_id": [
"g3p3ylz",
"g3p1t9s",
"g3p8zsp"
],
"text": [
"Depends on your usage. If it is a banner ad, they typically get ~.01-.2¢ per ad. Video ads can generate 2-10x that. So basically you would need to play less than ~100-20000 ads worth of time for the app to come out ahead charging a fixed upfront price.",
"Usually the ads just generate residuals so your free users aren't \"wasted opportunities\". The ads act more as a gateway for you to pay than an actual moneymaker. A very small amount of the free users will go into buying the ad-less version (depends on the app but it's usually less than 5% of the userbase)",
"Apart from the point that Subscription cost brings more money, it also buys the users' loyalty. You are more likely to stick to a platform where you paid to use an Ad free version. Hence, users lifetime value also increases. Which is also the reason why YouTube didn't have a premium ad-free offering untill there was competition."
],
"score": [
13,
11,
5
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
il61uv | Why is the music when you’re put on hold still so grainy/staticky? | Technology | explainlikeimfive | {
"a_id": [
"g3pmxua"
],
"text": [
"[Answered 6y ago.]( URL_0 ) TLDR; the old system makes the music gets super compressed for it to be sent through the phone, and the compression looses small details."
],
"score": [
4
],
"text_urls": [
[
"https://www.reddit.com/r/explainlikeimfive/comments/2awlcq/eli5_why_is_it_that_the_hold_music_for_all/?utm_source=share&utm_medium=ios_app&utm_name=iossmf"
]
]
} | [
"url"
] | [
"url"
] |
|
il916n | What do the parts of a PC do and what do the specs mean? | Technology | explainlikeimfive | {
"a_id": [
"g3qcmhv"
],
"text": [
"I like the office analogy. A computer is like an office, where you do work. RAM (memory) is like the desk. On the desk, you put stuff you need to look at now. If you have a large desk, you can have lots of papers and stuff spread out across it at once, even big blueprints that take up a lot of deskspace. RAM holds the stuff you are using now. If you have lots of RAM, you can run lots of programs at once, or programs that work with big video files, stuff like that. Your hard drive, or solid state drive, is like a file cabinet. It holds stuff long term, but to actually use the stuff you need to take it out of the cabinet and put it on the desk. A big hard drive lets you store more stuff long term. The CPU is the office worker. The office worker works with the stuff on the desk. A good worker does the work faster. Beyond this, the analogy gets a little weaker. The GPU is like another worker, but this other worker is good at uh, art and multitasking, just the CPU is good at drawing graphics for your videogames and doing certain calculations where you need to do lots of little things at once. The motherboard is like the room, it has to have space to handle all the stuff you put in it. The power supply, well, supplies the power, and needs to be big enough to power everything being used. This is a simple explanation, but I hope it helps you get started."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
il967m | One some devices, why do the wall plug-ins have a "test" and "reset" button and what do they do? | Technology | explainlikeimfive | {
"a_id": [
"g3qc2vz",
"g3qchg6",
"g3qckqh"
],
"text": [
"Those are Ground Fault Circuit Interrupters, they have an additional safety feature that detects abnormal flow of current. If detected it will open the circuit disabling the power to that outlet.They’re most likely around areas that can be exposed to wetness, such as bathrooms, kitchens, outdoors, etc.",
"Those are GFCI (Ground Fault Circuit Interrupter) circuits. Typically they're found in bathrooms and other areas where exposure to water are possible. They've got a built in breaker of sorts - if the current coming in is different than the current going out, the circuit trips (quickly, usually around 1/10th of a second). This is helpful if for example, someone's using a hairdryer and gets it wet which creates a short, drops some electronics into the tub, etc. It's also generally required by code for bathrooms and the like. The test button simply tests that the cutoff is working as intended, tripping the breaker. The reset button un-trips it so you can use the outlet again.",
"They are known as ground-fault circuit interrupter (GFCI) outlets. They protect people from being electrocuted. Think of them as chaperones at a school trip. The children (electricity) are moving from one place to another. The chaperones are always counting the number of kids to make sure they don't lose any at each of their stops. If the count is off, they stop everyone so no more kids wander off. The GFCI monitors the current flowing from the hot to neutral outlets. If some current is lost, the electricity could be going through someone so it physically shuts off the outlet to prevent more electricity from flowing. GFCI outlets are typically required in kitchens and bathrooms because water is conductive. You may also see them on hairdryer outlets. The Test button trips the GFCI to shut off the outlet. The Reset button connects the outlet again if it's tripped."
],
"score": [
15,
5,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ilc8u0 | What are website cookies and why does every website want me to accept them all? | Technology | explainlikeimfive | {
"a_id": [
"g3r08ct"
],
"text": [
"Cookies are little data files that can do everything from save your login sessions (to keep them active so you don't have to log in to a website every time you open your browser), saving display preferences for a site, aaaaaand.... tracking your browsing habits - Go to a news site and check out the Sports section a lot? Expect to see more Sports news on the homepage of that news site. Go to Amazon and search for unicorn plushies? Expect to see unicorn plushie ads on other websites. Sometimes that data gets sold, too. The EU passed a law in the last few years to protect individual users that requires websites to tell you they are placing cookies on your computer and what the function of those cookies is. It's to help you be more informed about what a site is collecting when you're browsing the internet and what they're doing with that data."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ilefpt | How do videogames mix/master audio on the fly without any audio clipping, while music software can't do it and bands need someone to do the mastering? | Technology | explainlikeimfive | {
"a_id": [
"g3rht6m",
"g3rswqe"
],
"text": [
"* First off mastering is the process of taking a recording and preparing for a specific medium like CD, MP3, vinyl record, cassette, Spotify stream etc. * So I don't think you mean to use the term mastering here. * Secondly, all the sounds that happen in a video game are created by the game. * It's easy to code the game such that it never generates a sound that would cause clipping. * Even when many sounds get overlaid together, the game engine is aware of the increase in level from the addition of all these sounds and can easily compensate for that. * Lastly, clipping can certainly be prevented by both software and hardware. * This is commonly done both in the studio when a recording is being made made and when tracks are being mixed down. * It's also done in the live setting when a band is on stage using devices called \"compressors\" and \"limiters\". * While the settings on those devices are set by the audio engineer, they aren't really touched or adjusted during the show so it really is the device doing the work.",
"Take Unreal Engine games as an example. There is a master submix object that outputs what you hear through the speakers. All the audio made in the game is sent to that master submix object. But the audio is (usually) not all sent without any forethought or organisation. It's grouped into more submixes like music, weapon sounds, ambient sounds, and so on. Each of those submixes can control the maximum volume they send to the master submix and the master submix can control the maximum volume it sends to the speakers. And the game's designer knows ahead of time how many sounds can be produced at any point in the game. You're not going to have a situation where there are 500 weapon sounds layered on top of each other. So the answer is the game's audio is designed or planned with 'overloading' in mind, and the game engine has methods to attenuate (reduce the volume of) the submixes as required. Either manually or according to some rules."
],
"score": [
10,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ilikxj | How different is C++ to C#? | How different is C++ to C#? I'm trying to get into game development in Unreal Engine as a C# developer, but I don't want to use 3rd party plugins like UnityCLR. | Technology | explainlikeimfive | {
"a_id": [
"g3se8od",
"g3sesav",
"g3sfdmd",
"g3skkti"
],
"text": [
"C# developed by Microsoft is more like Java and less like C++ Vast majority of game engines will be written in a fast language like C or C++. For unity, they have a scripting API that you can use C# for. You can use whatever language you like as well, just needs to interface with the C/C++ compiled libraries.",
"Moderately different. I use both at my work, and C# feels a lot closer to Java than C++. Perhaps it's due to how each of our apps use them, but C++ requires you to know a lot more about references vs pointers and stuff like. It's a good language to know though, as it is widely used, relatively fast, and the language supports a good number of features.",
"They're similar in the sense that most mainstream languages are moderately similar, but they're not related in any way. Don't worry too much about having to learn C++. If you know one language, you know them all, in a sense.",
"C++ is a lot more low level - you're basically developing closer to the hardware. Of course, because of that it can also result in a much more optimised performance. Basically a lot of the resource management stuff you have to do in C++ manually is automated in C#, but that results in a slower performance. C# is also made to be more human readable, so it's a bit more hand-holdy than C++. But really it depends on the context in which you're approaching this, can you give us more info? If you're just getting into it and you want to develop game prototypes quickly, I'd go with C# especially if you already know it. Learning game dev is one skill, learning C++ is another, you can make it easy on yourself and start with one of those, and it will help you stay motivated if you can relate your previous experience to the new experience. I don't know if you're coming from web/desktop or even mobile, but game dev is a looot different than the concepts in either of those fields so you don't wanna take too much of new learning at once. Again if you're just starting out I'd even recommend Unity as it's natively C# to learn the basic concepts of game design and make a couple of mini games and then maybe moving on to Unreal. There's a lot of great games out there that were made entirely in Unity, 2d/3d. Edit: Forgot the Blueprint functionality in UE4, it seems to be a way of visually blueprinting a game with predefined code patterns, without coding too much, but I don't know how it works in practice, it sounds a bit restrictive but who knows."
],
"score": [
13,
6,
5,
4
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
ilj5ex | How do computer parts keep getting faster and better? | Basically after watching the recent NVIDIA 3000 Series launch announcement, I'm wondering how is it that pc parts keep improving pretty steadily year after year. These tech Corporations say that they're using "new architecture", but what the heck does that even mean? Will we ever hit a limit on which CPUS/GPUS and pc parts in general can no longer be improved? | Technology | explainlikeimfive | {
"a_id": [
"g3sh9rx"
],
"text": [
"Not a computer scientist but i believe it comes down to physical layout of the parts internals, quality of material used in the part, and the software codes actually running through it, there's probably more factors but those are the biggest i can think of"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
iljy1f | How was there such a graphical leap between the original PlayStation and PlayStation 2? | The PS1 had such basic 3D graphics, so the jump to PS2 still seems crazy to me to this day. How did technology change so much in roughly 5 years? | Technology | explainlikeimfive | {
"a_id": [
"g3speim",
"g3snh9o",
"g3sug6g"
],
"text": [
"PS 1as release just when chips for 3D graphics chips for computer sated to be used on the consumer market. So they were quite crude and there was a lot of room for improvement. In a situation like that, the changes will be very large but when stuff get better any change will be less noticeable. You can compare it to aircraft. The first controlled flight was in 1903 and the manage to fly 260 m the first day. At the end of WWI 15 years later you had a long-range bomber that could fly 2000 km and bomb Berling from the UK. You had fast fighter aircraft and air battles with hundreds of them. It the last 15 years aircraft have improved but because they are a lot better any improvement make less of a difference.",
"Look at something called Moore’s law. Computing power is increasing in an exponential curve. In 40 years we’ve gone from room sized computers to ones that on your wrist.",
"A major reason is the exponential growth in the number of polygons that a system can draw. Visually, it makes a much bigger difference when going from a small number to a medium number than going from a big number to a huge number. Imagine you have 100 polygons to draw a character. They’re going to look blocky and they’ll obviously be made of polygons. If you get 1000 polygons, it really changes what you can do. Maybe hair is still hard but the body will look human, if that’s the goal. If you’re going from 10000 to 100000, though, you’ve already got a decently realistic character and now you’re just making fine details look better. Maybe now you can make realistic hair. It’s not that dramatic. At some point, there’s no visible difference. We aren’t there yet and the PS5 will look better than the PS4 but we’re never going to see the dramatic visual leaps of early console generation changes."
],
"score": [
21,
20,
7
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
illhup | How does the person I'm talking to on speakerphone not hear themselves through the phone? | It doesn't make sense that the person on the other line wouldn't hear themselves if I am using speakerphone/a Bluetooth speaker. | Technology | explainlikeimfive | {
"a_id": [
"g3t0it3"
],
"text": [
"Similar technology as noise cancelation is used. Since the phone knows exactly what's coimng out of the speaker. It can then block it from coming back in. Since sound is a wave, and oposite waves cancel eachother. The the phone simply takes the speaker wave, flips it, and finally mixes it with the mic input. This process mostly eliminates the speaker sound. In reality more complex algorithms are used."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
ilmsit | Why are some programming languages so complicated while others are so simple? | For example, the "hello world" program in Python: `print("Hello world")` The "hello world" program in C++: `#include < iostream > ` `int main() {` `std::cout < < "Hello world";` `return 0;` `}` Why is Python so user friendly while C++ is not? Or am I missing something here? | Technology | explainlikeimfive | {
"a_id": [
"g3t8aax",
"g3t7sqg",
"g3tkjeg",
"g3tih7g",
"g3tyrfz"
],
"text": [
"There are several language features used in your C++ program that are not present in your Python program: - The #include directive is very useful in reducing compilation times, which can be many minutes in large projects. This has a direct benefit to programmer productivity, and reduces the temptation to go on Reddit. - The int main() part defines a function. Functions are critically important to programming anything other than the smallest programs because they help you subdivide the program into more individually-manageable bits. The “return” statement illustrates this well: the caller should only care if it succeeded (returned 0), not how it does its business. - The “std” part references a namespace. Namespaces make it easier - again mostly benefiting large programs - to use the same name for different purposes, instead of forcing one module of the program to have to rename things to accommodate another. In other words, the C++ program contains what is merely boilerplate code for your very simple example program, but are actually important features for managing the complexity of big programs. Beginner-friendly languages often lack these features, and are consequently not favored by professionals who need to work on these big programs.",
"C was written in the 1970s when programs were mostly written in Assembly, which is a \"human friendly\" (relatively speaking) version of the language the native language the machine itself understands. It would then be \"assembled\" into machine code and run. As a result, it was designed to be as easy to translate to machine code as possible, so that programmers who understood the how the machine underneath worked could eke out every bit of performance. Generally it's mainly still used where performance is critical and low level machine access is needed. C++ was developed to make C \"object oriented\", which has some disadvantages, but it's generally almost as quick as C, while frequently easier to program in. In the decades since C was first developed, compilers (programs which turn code into programs) have gotten much better. As a result, programming languages have diversified. Python was written from the start to be human friendly. It doesn't have the performance of C or C++, but it's generally much quicker to write a program because that was its goal.",
"What you're missing is that: 1. Python was designed to be user friendly, C++ was designed to add features to C which was designed to closely align to machine code 2. There were 20 years of computing advancements between C and Python 3. C/C++ is more powerful than Python 4. That C++ code will compile to an executable of like, a couple KiloBytes, the Python code several MegaBytes 5. The C++ code will execute in a fraction of the time of the Python code",
"This is kind of like looking at an old 80's Chevy and asking why it doesn't have all the fancy features that your modern 2012 BMW has. C++ is a language that hails from an era where storage and processing power came at a premium. Therefore, C++ assumes almost nothing about what you want in your project. If you need extra tools, like the ability to print to console, you either have to write it yourself, or explicitly tell the assembler that you want to include a library that already wrote it for you. On one hand, this can *massively* cut down on your program's final compiled size, but on the other hand, it can take an uncomfortable amount of importing things and writing boilerplate to get even the most basic things done. Python was designed specifically to be a user-friendly, no-bullshit language. It includes a lot of standard library functions into every project, as well as provides a lot of \"syntactic sugar\" for performing common operations. Python can afford to be like this because, in environments where you're most likely to be using it, the hit in performance and storage is negligible.",
"Hello world in Python is really something more like: def main: print(\"Hello world\") if __name__ == \"__main__\": main() As part of a \"proper\" program you can extend to actually be useful. This isn't really any less complicated than the C example. Python has taken a lot of choices so you can build up to more complicated code, but when you start writing complex code in C, Java or Python it does end up looking quite similar."
],
"score": [
19,
18,
7,
6,
4
],
"text_urls": [
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
ilosqo | What do all the stats of Graphics Cards/GPUs mean? | So I was reading [this article]( URL_0 ) about Nvidia's new Ampere architecture, and it has a whole table full of stats of the different 3000 series cards, and aside from basic things like VRAM, VRAM Speed, and wattage, all the stats just look like jumbles of letters and numbers to me. Like what is a CUDA core, and what makes it different from a RT Core or a tensor core? Is boost clock the same as clock speed or is it something else? What are all the different Tera/Giga flops? & #x200B; Any help is much appreciated! | Technology | explainlikeimfive | {
"a_id": [
"g3tit6a"
],
"text": [
"CUDA, RT and Tensor cores are essentially processing units meant for specific tasks, or for co-processing off of your GPU. This means offloading a task off the actual GPU cores, and delegate the process to something that can do it more efficiently, and freeing up some power that wouldn't have been used in a optimized way. A boost clock is a temporary increase in clockspeed (or overclock), as long as thermals allow it. Tera/Giga flops is a performance metric, that really doesn't mean a lot as it isn't applicable across the board to gauge actual performance."
],
"score": [
11
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
iloumv | If cameras are round, why are photos square? | Technology | explainlikeimfive | {
"a_id": [
"g3tikkb",
"g3titzk",
"g3tiwxz"
],
"text": [
"The lens is round because a rectangular lens makes weird AF images and is a monumental pain to make anyways. The digital sensor (or the hole leading to the film) itself is rectangular. Yes, this means some of the image produced by the lens doesn't make it into the hole and gets snipped off.",
"Honestly, it’s because that’s the established format. When photographs were first a thing, they were plates of silver halide crystals that were slotted into a box, and then flash powder would be set off while quickly and briefly exposing that slide to a scene, through a lens that focused the flash. This would burn some crystals while leaving others intact, allowing for a photo to be copied from the “negative” later on. As technology advanced, people continued to use square form factors in photographic technology, and then later when video was invented.",
"Circular images are a little weird in general though no? Back in the days of film, it was likely considered but very quickly scrapped. Turns out you can make a long strand of rectangles (film) without wasting much material, but can’t do the same for a circle. In the age of digital cameras, having circles also complicated things because the tiny sensor components are rectangular as well, and building rectangles out of rectangles tends to be easier than building circles out of rectangles. Given that pixels also tend to be rectangular structures and digital images were just stores of pixels, the rectangle lived on."
],
"score": [
27,
8,
6
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ilul8u | How do movie theaters project the movie onto the massive surface area without it looking blurry/low quality? | They record movies in like 1080p or 4k right? How come those pixels look so clear on the big screen? Yes, I imagine the answer to this is quite simple but I can't seem to wrap my head around it. | Technology | explainlikeimfive | {
"a_id": [
"g3unkkw"
],
"text": [
"Actually, the cameras still often record on film which is technically pixel-less (analog).. therefore when played in theaters, as long as it's in focus, it's clear. They're also using projectors in the $200,000-400,000 range, and those who do use digital projection are using higher end laser projectors or multiple projectors, like Dolby at AMC."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
ilv1jy | why do some games only work on windows? | Technology | explainlikeimfive | {
"a_id": [
"g3v2nc3",
"g3v3efg",
"g3urnki",
"g3v80k3",
"g3v39s3",
"g3xlfjz"
],
"text": [
"Games are rarely made completely from scratch, instead they're built using existing tools and frameworks which are known as APIs, or application programming interfaces. An API is a list of documented functions and the parameters they take that perform a known action when called, an example of an API to draw a circle might be: drawCircle(int x, int y, int radius); You don't need to know how it works internally, only that so long as you use the API as documented it should give you the outcome you expect. Those APIs themselves may be built on other APIs, which may be built on other APIs. In many cases you'll eventually hit upon an API which is part of the operating system itself. In gaming, the big one is called DirectX and is the Microsoft API for, amongst other things, game programming. It's an abstraction layer built around other APIs such as graphics card drivers that presents a unified interface for development on Windows machines (and the XBox consoles). If you're writing an application and part of the API hierarchy depends on APIs that are only available on Windows, then the application can only run on Windows. Now there are two ways around this: 1. Certain APIs are designed to be completely independent of the operating system they run on. Often times these APIs have a general way of doing things, but can be re-compiled using special flags that will utilise specific operating-system specific APIs for the sake of performance, but the key thing is that their actual API (the functions exposed) don't change between hardware or operating system type. 2. The reverse of 1, people take platform specific APIs and emulate them by creating a substitute version on a platform that was not intended to run them. This is how the popular Linux application 'Wine' works.",
"Some games, like tick tack toe, are easy to play on windows, especially when there's condensation. Some games like darts are best played on doors or walls.",
"Because the people who write the games implement them by calling functions that are built into windows. If your PS-4, or whatever, doesn't implement those functions, the game can't work.",
"The machine and the software need to speak the same language. If the machine only understands French, an English program won’t work. You can rewrite the program for a specific machine, like translating it to French. However, it isn’t always easy, you might have to rework whole parts because of major differences, for example, French has genders, adjectives are placed after nouns etc. That is what is happening when a game is released for PC, Ps4 and Xbox etc. The developers adapt the game to each machine. But this is huge work and therefore developers will only do it when they are confident they will get a return on the investment. You can also do the translation on the fly, realtime, that’s what emulators do, when you play a nintendo game on your pc or when you play a PC game in Wine on Linux. These hurdles are the one of the reasons game engines like Unity and Unreal engine are popular choices, because they reduce most of the work required to release a game on multiple platforms.",
"For the purposes of this question, Windows is just a way of letting Software and Hardware talk to one another. The software knows how to talk to Windows, and it lets Windows tell the hardware what to do. If you know most of the people that want to play your game are on Windows, it's easier to make your game like this. Games that work on multiple platforms have an extra layer. They talk to a middleman, and the middleman knows how to talk to whatever system the software is trying to run on. If you want to make it work on a new system, you only need to retrain the middleman, not the whole game. Unity is a popular example of a middleman here. It's often a bit slower, but that can be worth it if you're trying to reach a bigger audience.",
"Computers use software to know what they are doing and to perform tasks. Think of software as Lego bricks. You have a base layer to start everything from which is your Operating System (Windows), then you build upon it with more layers to achieve your goal, like building a skyscraper. In this case, you want to play a video game. There are many layers of bricks that need to be laid down before you can do that. The video game itself could be considered the top of the skyscraper, but you need everything in between or else the top won't connect properly. Since Lego is the most popular brick to build with, the developers of your video game may only make building plans and blueprints that use Lego. Some larger projects, or generous developers make plans that use Mega Bloks (Mac OS) as as well, or maybe even Sluban (Linux). This isn't always the case, however. If you've built your base and middle layers of your project out of Mega Bloks, the Lego at the top isn't going to fit properly and work."
],
"score": [
76,
41,
32,
13,
9,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ilxemq | Why are submarines so hard to track with modern technology? | This is sort of a "where's my flying car" kind of question, as in, I would have thought we'd be at the point now where hiding a giant tube of metal under the water would be impossible. From super-duper microphones to super-duper sensitive electronics to super-duper spy satellites to super-duper budgets placing super-duper gadgets all over the ocean floor, how do modern submarines manage to evade being tracked? | Technology | explainlikeimfive | {
"a_id": [
"g3vd5v7",
"g3ve456"
],
"text": [
"It is mostly just a factor of how damn big the ocean is. Even a surface boat is likely to avoid detection simply because there is so much ocean that it can be hard to find it. Also, submarines have a lot of the same sensor equipment that other ships do, and other ships generally aren't trying to be as stealthy as submarines are. which means that a submarine can very often detect and avoid the ship that would otherwise detect it.",
"It mainly comes down to that 1. the ocean is massive 2. Submarines are designed specifically to counter the technology that could be tracking them (special coatings etc) 3. Water is really hard to track stuff through. Radio signals really do not travel well through water. So radar won’t work, or tracking devices based on radio signals won’t work. This is why SONAR is used underwater, because that’s based on sound waves, but because of that it also has pretty limited range. A few miles for real accuracy, further in better conditions, shorter in worse conditions. This means that a ship has to cover and scan a lot of possible ground for the submarine, while the submarine can spend that whole time actively trying to avoid it."
],
"score": [
6,
4
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
ilxnp7 | Why haven't email attachment file size limits increased over the years? | Technology | explainlikeimfive | {
"a_id": [
"g3vecjv",
"g3vi13j"
],
"text": [
"One big problem with email is that, if a message has multiple recipients, the entire mail message is duplicated for every recipient. If some company has 1000 employees and someone emails out a 5MB PDF to all employees, then the mail server will need 5GB of space for all those emails. In addition, the protocols that handle email inboxes means that you have to download the whole of waiting email. You can't easily pick and choose what to download. If you send someone an overly large attachment, it can prevent them from accessing their inbox at all (This is even a problem for webmail systems which have to handle all the processing of these files, which can cause server-wide problems)",
"Email is not a file transfer protocol. Email by design allows for unsolicited messages to be delivered, so if you allow attachments of any size a hacker could very quickly overload your server and fill up it's hard drives by sending emails with multiple recipients and large attachments. For example if I can email a 5gb ISO, It would only take a couple of emails for me to crash your server. Email attachment size limits have increased over the years but it's rare to see larger than 20mb for the above stated reasons."
],
"score": [
9,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ilzcyk | How do ad blocks work, and why can some ads come through on certain sites? | I have an ad blocker installed on chrome and it works pretty much 100% effectively on youtube, but on reddit I always have ads on the side of my screen. Why would it work for some sites and not others? How does it even work in the first place? | Technology | explainlikeimfive | {
"a_id": [
"g3vvyd2"
],
"text": [
"Adblockers have a list of websites and HTML elements within those websites that contain ads. When you load a page, it checks its reference list, and then deletes the elements that contain the ads. If there's an ad in an element that isn't listed, it won't get deleted. Most adblockers have a function where you can add to the list by right clicking on an ad and telling it to block it. This just adds it to the list."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
im0lau | shader tflops vs raytracing tflops vs tensor tflops | Given the recent release of the RTX 3090, I noticed there are three different teraflop numbers listed: shader tflops, raytracing tflops, and tensor tflops. I thought a teraflop was just a measure of operations per second, so it shouldn't change if the hardware isn't changing. Does this mean the operation speed somehow varies depending on what you're doing with it? | Technology | explainlikeimfive | {
"a_id": [
"g3w6fr2"
],
"text": [
"Basically you're dealing with different cores in the GPU. They all have a different amount of cores. For instance the 2060 has 240 tensor cores, 30 RT cores and 1900 shader cores."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
im1vb6 | Bluetooth? | Technology | explainlikeimfive | {
"a_id": [
"g3wk5vi"
],
"text": [
"They’re basically just low powered radios. They communicate via radio waves the same way as your phone communicates, your computer to your WiFi, and your radio to the radio station. Bluetooth in particular is very low power but also low latency. At 2.5 GHz you can communicate a decent amount of information fairly quickly. All of this tech works roughly the same way which means information is modulated, sent via rf waves, reconstructed, then channelized, then sent to the new device. Bluetooth will usually skip the reconstruction and channelization phase. Let’s break this down! You talk into your phone and this creates sine waves at exactly the same frequency as what you talk. However, this 30KHz signal is too low energy to be sent like this and also everyone talks at the same frequency! Instead what you do is you place your signal on a much faster frequency that only you are using. This new frequency is much higher energy signal and can be sent with radio waves really easily. Now you let it fly with this new higher energy. This is called modulation. Now your signal is really high energy and easily passed around the room! It gets to your device which knows what frequency you sent it on. It removes that frequency and all you’re left with is your original voice."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
im2x73 | Why can’t we use seeds to generate file downloads instead of downloading the whole file. | I hate to use minecraft as my best example but we can generate a whole world in 20 characters to create a world (obviously larger than a 20 character string in raw size.) Why can’t we extend this to file downloads and instead of downloading a movie, I download a movie seed and replicate the movies data from this seed and now we hypothetically download a movie faster than normal. | Technology | explainlikeimfive | {
"a_id": [
"g3wqh66"
],
"text": [
"That's essentially what compression is. The thing with Minecraft is that its world isn't usefully deterministic: you can't really control what that seed does. It's setting the nobs on a giant book of rules that creates a random world that is still going to look *very* similar to all other Minecraft worlds. This is pretty useless when your aim is to create a specific thing. Imagine having to actually find what seed creates the *specific* world you want if you're not given it beforehand: you'd pretty much be screwed. You'd have to test each of the trillions and trillions of possible 20 character strings - and that's assuming one of them will create that world at all. Imagine a world where I built a castle. No matter what seed you put in the giant book of rules will *never* create that castle I made. Compression revolves around trying to take *existing* data, and finding some way to represent it in as small of a space as possible. At some point you'll either have to stop, or you throw away some information you think is useless in order to make the \"seed\" smaller."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
im3ccs | What or why do geiger counters make this "krkrkrkr" sound when measuring radiation. | Technology | explainlikeimfive | {
"a_id": [
"g3wtlle",
"g3wxprs",
"g3wxvs2"
],
"text": [
"Basically 1 click is a single radiation event the more clicks the more radiation, when the clicks merge into a continuous noise get the hell out of there.",
"The electricity can go though the Geiger-Miller tube only if it’s hit by radiation, so when this happens, it sends electricity though a speaker and it makes a click noise, if there is a lot of radiation, or goes form a click to a rkrkrkrk and then to static",
"Geiger counters are used to usually detect two things, beta particles and gamma rays. There is a tube in this apparatus which is filled with a special kind of gas. When a special type of particle hits this gas in the tube it can conduct electricity. The radiation can penetrate the tube and rubs with the gas, releasing electrons, if this happens enough there is enough electricity to flick a switch \"krk\". Lots of \"krks\" is lots of ionisation happening."
],
"score": [
13,
6,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
im61j8 | Why is USB-C so much better than other connectors and why are so many enthusiasts obsessed with them? | Technology | explainlikeimfive | {
"a_id": [
"g3xiyxx",
"g3xjz65",
"g3xj3xi"
],
"text": [
"Basically, it's the \"one connector to rule them all\"...it does basically everything you need outside hardcore technical things. It does power, network, peripherals, multi-screen 4K video...all at once. If implemented properly. And unlike !#!#\\^!\\^ USB-A, it's reversible so you don't need to rotate it twice to get it to work. Once fully adopted, it should theoretically allow one connector for all devices and all needs in the consumer realm.",
"It’s like comparing a cross-threaded garden hose to a 6” firehouse. WAY more power capacity. Huge pipeline for data. Dummy proof durable connector. Because it handles way more power and data, it can power big devices easily while handling loads of bandwidth.",
"Two key points 1.) It's a reversible connector (it can still work if plugged in upside down) 2.) It supports the higher data transfer speeds of USB 3 and subsequent revisions FAR more elegantly than the Micro B 3 connector, and has a few extra pins that can be used for other stuff, like video output."
],
"score": [
11,
5,
5
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
im8ryk | How does airdropping work? How does the information travel locally? | Technology | explainlikeimfive | {
"a_id": [
"g3y60ip",
"g3yke20"
],
"text": [
"One device yells at another device, and that device writes down what the first device is yelling. That’s it. That’s how all wireless communication works. We can’t hear devices screaming at each other because it is so high-pitched, it’s outside of our range of hearing.",
"AirDrop: two computers use Bluetooth to establish a connection over WiFi, which they use to transmit the data. ELI8?: two computers hand shake over Bluetooth and one computer download data from another computer over a local “internet”"
],
"score": [
10,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
imcfx5 | How my vehicle still keeps the set time even after a long period off? | Technology | explainlikeimfive | {
"a_id": [
"g3yn5fy",
"g3yp91a",
"g3z5z6v"
],
"text": [
"They usually run a very small charge directly off of your car battery, to keep the info intact.",
"The clock uses some power from the battery, but it’s so tiny it barely depletes the large capacity of a car battery If your battery dies or something is wrong, the clock will reset to 12:00 The same is true for laptops and phones, that’s how they keep time when off, desktop computers have a tiny battery for the clock",
"A lot of modules on a vehicle are separately connected to the battery and an ignition/accessory wire. When the car is turned off, it still has power and can enter a low power state to avoid draining the battery. In this low power state, it'll simply manage the bare minimum necessities (such as timekeeping). If you disconnected your radio from the battery entirely (or drained your battery), you likely would see the time reset."
],
"score": [
11,
7,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
imcw5q | How does quartz power the quartz powered watches? | Technology | explainlikeimfive | {
"a_id": [
"g3ypfrg",
"g3yqw5a",
"g3ypfpi",
"g3yryqf"
],
"text": [
"It does not. The quartz resonates at a specific frequency which is divided down, using an electronic circuit, to produce 1 second pulses that drive the mechanical escapement that moves the hands. Quartz is used because the frequency stays relatively constant with variations in temperature. The watch is usually powered by a small battery, or more rarely by some sort kinetic generator that converts motion from the wearer into electricity.",
"A quartz crystal has two very nice features : 1. It mechanically deforms when you apply a voltage across it 2. This deformation is really stable and predictable; it doesn't change much with temperature, aging of the crystal... (as in, less than 0.0001% change) At a certain electrical frequency - which depends on a number of factors, such as the way the cristal is cut, the dimensions of the crystal, etc... - the quartz crystal will resonate wih the electrical voltage - the AC voltage will deform the crystal in a certain rythm, and this rythm will create an AC voltage, in a way that perpetuates itself with almost no losses. This resonance is extremely steep. At frequencies barely above or under the resonance frequency, the losses will be very large, but at the exact resonance frequency, it will be almost zero. The crystal acts like a club bouncer : it will stop almost everyone, and let only one frequency through. This is of course very useful for an electrical engineer, since you now only have one known & very stable frequency in your circuit. From that, it's fairly straightforward to drive a watch. You can simply count the peaks in your AC signal, and once you have counted enough peaks you know a second, minute or hour has passed; you then activate a tiny motor and you move the corresponding hand. Since the whole thing uses very little energy (as we said, almost no losses at resonance !), your watch can be powered for years with a simple battery.",
"It doesn't. The power for a clockwork always comes from a spring-loaded mechanism or a battery. A quartz crystal only provides a steady \"rhythm\" as a reference point for the clock timings.",
"We have to explain a few concepts before. Piezoelectric effect, this is when a ionic structure crystal is compressed, it produces a set current, Depending on the shape, composition and structure of the crystal the current will be different. The good thing about the Piezoelectric effect is that its reversible, meaning that if you inject current in to a crystal, it will vibrate at a specific frequency depending on shape, composition and structure of the crystal if you inject a specific current, it will vibrate at a specific frequency. A quartz watch is a simple controller, it measures 32Khz which is the frequency a quartz crystal in a watch produces and when it counted that frequency, it moves the seconds hand 1 second, every 60 second hand movement it moves the minute hand and every 60 minute hand movements it moves the hour hand. The curious thing is that quartz watches existed for a long time, but they couldn't find a way to make the quartz crystal small enough and maintain the accuracy, until they discovered that if they cut the quartz crystal in to a tuning fork shape and use small amounts of metal on the prongs for fine tuning, they can make the quartz oscillator small enough to fit on a wrist watch."
],
"score": [
15,
6,
3,
3
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
imdzwn | How the front-end of a website communicates with a server side language? | Technology | explainlikeimfive | {
"a_id": [
"g3yxd7v"
],
"text": [
"So the original way it was done is that the user would make a request, and the server would respond with the content. This means that any server-side processing happens only at the time of request (ie. prior to the initial page load). You can send data from the front-end to the back-end using GET or POST parameters, usually either by submitting a form or by clicking a link with some parameters appended to the target URL. This meant that if you wanted to create an interactive application, you'd need to build it out in \"steps\" of multiple pages or just continue reloading the same page every time something changed. Not ideal for a user experience, so that's where AJAX (Asynchronous JavaScript and XML), comes in. You can have JavaScript listen for user interactions on the front-end of a page (like a change to an input field) and then perform an AJAX request to the server with that changed data. The server processes it and then returns some data that you can use to update the page - the key here is that this server processing is done asynchronously and doesn't require a page reload (you can kind of think of it as happening \"outside\" the current web page) so for the user it's a more seamless experience. This is a fairly basic example and there are a lot of front-end frameworks (Vue, React, Angular, etc.) that handle a whole bunch more of the business logic - stuff you would in the past have needed to do server side. Under the hood they're still using AJAX calls to fetch data from servers though."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ime4fz | Why does porting one video game from one platform to another take so long? | I love video games and play a lot but know nothing about the technical development of one. But basically, I want to play Fall Guys, haha. I’ve got a Switch and from what I’ve seen it’s coming to the platform, but it needs to be “ported to work for Switch.” I just wonder why that takes so long, or if that’s even the reason at all? Thanks ! | Technology | explainlikeimfive | {
"a_id": [
"g3yxtqh",
"g3yxch5",
"g3yyef4"
],
"text": [
"Each platform runs on different software, adjusting settings and graphics from one to another can be tedious depending on changes needed. More often than not the delay is caused by marketing contracts. An example would be (no idea if this is true with Fall Guys) a game signing on to be exclusive with Microsoft for X amount of months until it could be released on another platform.",
"Have you ever tried putting a DVD in a CD player? It’s not in a compatible format and needs to be coded to run on the hardware and the Switch OS. The Switch and the PS4 also don’t have the same specs so it needs to be a build that the Switch can actually run. There are other things that need to be done but as far as I know it’s the rest is fairly simple. (controller remapping in some cases, but from console to console this isn’t as much of an issue as porting something to/from PC. Even then this isn’t the biggest of deals either.)",
"The computer language on the switch is different than say a PS4. The hardware is different. The team that works on the code for the switch is probably different or maybe not. They have to take all of the Fall Guys code and translate it into a completely different language and compile it for a different processor. Almost like rewriting it completely. Yet it has to work the same. It has to undergo testing. It does take months and months."
],
"score": [
8,
5,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
ime93i | Why does it take longer to delete a bunch of files together, as opposed to deleting them individually? The size of the deletion is the same in both the cases | Technology | explainlikeimfive | {
"a_id": [
"g3zv2fy",
"g3yzmjk",
"g41bp2r"
],
"text": [
"Pretend you have a football field, and 100m of string laid out in a line: it’s pretty easy to walk along it, and pick up the string. Now if the string is cut into pieces and spread all over, you still have 100m of string but you’ll have to find it all and go to it to pick it up",
"Was the hour just the estimation in the beginning or the time it actually took? If it was just the estimation, then the OS probably saw 200GB of files, started deleting small ones and it needed 5s to delete 100 small files with only a few KBs size and extrapolated the time for the few KBs to 200GB, but it would have gone way faster, because a few large files don't take much longer than small ones.",
"It’s not because of the file system or anything else like that. It’s because Windows wants to show you an animation with counts, estimates, etc. Calculating this takes time. When I don’t care about the estimate, I open up a command line window and delete from there. It doesn’t pre-calculate an estimate and I save time with the process. Sometimes I do this *after* I already tried deleting it from File Explorer. The files would get deleted by the command line process while File Explorer is still stuck in the calculation step. Yes, seriously."
],
"score": [
25,
24,
4
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ime955 | Are end-to-end encrypted apps like WhatsApp protected against backdoor in system? | I want to know if such a backdoor would enable the attacker to bypass the app encryption and see the messages. For example if a company hid a backdoor in their custom layer over Android, I am assuming every activity in that phone is compromised. | Technology | explainlikeimfive | {
"a_id": [
"g3yy6i0",
"g3yyhf3"
],
"text": [
"The messages are end to end encrypted, meaning that they are encrypted between the sender and the receiver, but in the sender and receiver’s phone they must be unencrypted in order to be readable, so if you get access to a phone, whether physically get it and unlock it, or with a backdoor, you can access the messages in theory",
"Yes, this would be possible. The \"end\" in end to end encryption is used to refer to the end device but it does not protect from attacks against the device itself, or between the device and the person using it. If someone had control over the device, for example if they were running screen capture software, then there is nothing the application can do to protect them from seeing the communications."
],
"score": [
5,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
iml97q | Why can't we simulate a perfect sphere? I've always seen spheres in games or simulations where they're always using hundreds of thousands of polygons to make the sphere. Wouldn't it just be easier to render a perfect sphere? | Technology | explainlikeimfive | {
"a_id": [
"g40rv2b"
],
"text": [
"Modern render engines still use triangles as the base component. A perfect sphere has no flat portion so it can only be approximated by increasing the number of triangles. Traditional raytracing allows you to define geometry so theoretically we could render up a perfect sphere, but I believe the real time raytracing is using some photon mapping techniques and still working off the triangle pipe."
],
"score": [
10
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
imnhiz | Why do movies look weird in 60fps? | Technology | explainlikeimfive | {
"a_id": [
"g41bs0c",
"g41deqt"
],
"text": [
"Weird is subjective but probably cause the industry standard for films is 24fps so you’re just not used to 60fps",
"It’s always been my thought that the way humans look around isn’t smooth and linear the way a lot of video media is portrayed. When we look around our eyes typically “dart” or “skip” in a particular direction as we look to it, when that happens the picture (of what we’re seeing) changes in an instant or in some cases it’s just a “blur”. That’s why I would imagine they might have added “motion blur” as an effect in cinematic video games; to make it seem more realistic. Lower frame rates provide a pseudo built in motion blur look to it but it’s enhanced by adding further artificial motion blur. The end result is what we’ve always seen in movies and that’s why it’s different from the natural way our eyes perceive light. Long winded I know, apologies. But that’s what I think anyway. Edit: I didn’t answer your question lol. 60fps adds more “info” to the picture if you will. That’s different from what we’re naturally used to. Therefore the weird comes in."
],
"score": [
7,
6
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
imqp71 | Why when your phone is on speaker, the person on the other end doesn't here themselves | Technology | explainlikeimfive | {
"a_id": [
"g42ho84"
],
"text": [
"Depends on the phone of course, but one method of eliminating this feedback is by using the signal that’s being sent to the speaker and essentially “subtracting” it from the signal coming in from the microphone. That way you only pick up sounds coming from outside the phone. Most phones also use the microphone next to the back camera in order to eliminate ambient noise from the environment you’re in."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
imr286 | Why does it cost so much money to make international phone calls? | Technology | explainlikeimfive | {
"a_id": [
"g428zxn",
"g42dyzn"
],
"text": [
"Because you'll pay for it. The cables on the sea floor may have something to do with it too. But in reality, demand is the true denominator that controls prices.",
"They don’t in this day and age, when you can and provably should use the internet to make international “calls”. In which case you will pay nothing extra."
],
"score": [
11,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
imrbbg | What is the number lock keyboard function useful for besides driving me crazy when it is either on or off? | Technology | explainlikeimfive | {
"a_id": [
"g42au1w"
],
"text": [
"If you have a number pad on your keyboard it locks in the functionality of using as a number pad, such as for using the calculator application on your computer of for excel. With numlock off, certain numbers as directional arrows instead"
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
imuotz | If nearly all locks can be picked, why do people still use them? | I've been watching a lot of LockPickingLawyer recently and I'm really starting to feel like locks are just an illusion of safety to protect you against people who don't know how to pick them. If my original question comes down to "most people aren't that good at picking locks" then can you also ELI5 exactly \*how much\* better LockPickingLawyer is than your average lock picker? | Technology | explainlikeimfive | {
"a_id": [
"g42yf1v",
"g42yhlu",
"g42ymjz",
"g42ypaj",
"g42z6g2"
],
"text": [
"Because the idea of a lock was never to guarantee protection, but just to make yourself a harder target. Why would a thief steal from something that is locked when there’s something unlocked down the street. Or why would a thief risk spending half an hour of getting caught to pick a hard lock, when there is an easier lock down the street. Locks are like castle walls, they’re not impossible to get over, anyone who makes them know they’re not impossible to get over, the idea is just to make it harder to get over/get through than it is worth.",
"Security measures (physical or technological) are usually more about making yourself a slightly more difficult target. Picking or bumping most residential locks is trivial. For someone inexperienced, it will still take time. Kneeling in front of a door to pick a lock for a few minutes is long enough to get someone caught. A random burglar will usually look for the easiest mark. A locked door is there to convince the general criminal to try an easier mark. If someone has it out for you personally, there’s not much you can do realistically.",
"Most security features you'll see day to day really only keep people from acting on an opportunity. Say you're walking around and happen to see an unlocked bike. You just take it and leave, and you're done. On the other hand, say you're walking around and happen to see a locked bike. Nothing happens because the lock is too much trouble to be worth it. But if you're *looking* for a bike to steal you'll probably have something to cut a bike lock and it won't matter. If someone plans on getting in they probably will. But if they're not planning on it, locks keep you from becoming a victim of opportunity.",
"I get the impression from some of his videos that he is exceptionally good, it sounds like he's won a few bounties or competitions and stuff. But yeah, it largely comes down to the idea that 99.99% of people can't pick locks at all, let alone their skill level in it. Most crimes on locked things are just done with bolt cutters or hammers and stuff, not picked open. Better locks and better security and stuff is really just a deterrent by raising the difficulty level, if someone is actually planning to come with the right equipment and stuff they'll always beat the lock. The idea is to just make that not worth it or too hard to do without being caught. You're trying to make sure there's no 'crime of opportunity' and other targets are easier than yours.",
"Well first off, yes most locks are very simple to pick. You probably could learn with a good teacher in under 30 minutes. However, most burglars aren't going to go through the trouble. It takes 2 seconds to kick in most doors or break a window with 0 training required. Add on to this that in some jurisdictions, simply carrying a set of lockpick (considered burglary tools) without working for a locksmith, is considered a misdemeanor based on the idea that simple possession of the tools shows the intent to use. So in reality it's never the lock that's defeated, usually it's the door or the door frame. So having a high security lock on an low security door is like securing a vault door with a knotted rope; ultimately pointless. However, yes lockpickinglawyer is just that good as well. A lot of locksmiths won't even go through the trouble of trying to pick a lock anymore. They'll drill the lock cylinder out and then offer a \"sale\" on a new lock cylinder to replace the one they broke. Technically, it's not a scam but it's kind of scummy. Lockpickinglawyer on the other hand is a hobbyist, he enjoys defeating locks and does so in his free time. As such, he is particularly skilled."
],
"score": [
49,
16,
10,
9,
6
],
"text_urls": [
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
imuoxl | Why is it when too many people talk at once in an audio program (think Zoom, Discord, Google Hangouts), the sound that you hear becomes distorted (as opposed to just a combination of all of the voices)? | Technology | explainlikeimfive | {
"a_id": [
"g42y8nl"
],
"text": [
"Because the program isn’t an audio recording program, it is an audio transmission program. It isn’t meant to compile multiple inputs at once into one sound. It just hasn’t been designed to work well like that. Zoom is very much meant for a audience that isn’t supposed to be talking all over one another, but for meetings/now teaching where only one or two people are talking at once, so that’s what it’s designed to manage with. I’ve never used google hangouts, but in my experience discoed does actually do an extraordinarily good job at managing a bunch of people talking at once."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
imxgjg | I recently read somewhere, when the Unreal Engine 5 launched, that the developers got very concerned and disappointed that they were not able to achieve great difference in graphics and realism even though they increased the number of triangles to billions. | What is the difference between this and the technique used in the movies to achieve incredible realism and graphics? How are the game developers going to tackle this problem? | Technology | explainlikeimfive | {
"a_id": [
"g43ktvw",
"g43sfek",
"g43rmpb"
],
"text": [
"I'm not sure exactly what you're referencing in the title but it's become pretty common that whenever there's a big engine update there's a discussion of \"diminishing returns\" - the idea that adding more and more triangles and increasing the fidelity of lighting and so on gets progressively less impactful the more you do it. So the earlier graphics breakthroughs seemed more impactful - the leap from 2D to 3D in gaming was obviously a massive revolution in gaming graphics; going from simplistic polygon 3D graphics to more realistic was again another game-changer, and so on. But today's updates by comparison seem less impactful even though the technology is actually evolving at an even faster rate than back then - going from hundreds of thousands of triangles to millions of triangles just doesn't seem as groundbreaking because the hundreds of the thousands of triangles was still pretty good for everything it was being used for. Or so the thinking goes. On the other hand, graphics that seemed unbelievably realistic in 2010 now seem pretty bad a decade later so a lot of this is driven by people's perception of things. So it's debatable really whether or not this is even a thing. Movies are different than video games. Simplified, in video games, we have to generate all the images \"on the fly\" because the camera perspective can change, lights can move around, objects change position. In a movie you only need to generate all the images once because every frame of the film doesn't need to change after it's generated, it will always be that same frame every time anybody watches the movie. So you can use a giant sever farm and take weeks and weeks to generate all the images once and then you're done.",
"Unreal Engine 5 hasn't been released yet, they've previewed a couple of features but nothing in detail. It's not expected to be released for at least another year, so we still have a long time to wait. The main feature that Unreal Engine 5 is promoting to developers (and the devil is in the details of course, which we don't have) is a much improved workflow which will reduce the time and effort required to produce content for games. There are diminishing returns on trying to achieve photorealism. That means it take lots more effort for smaller gains. This is true in non-realtime rendering too. But new technologies can make leaps though.. we saw that with the move to PBR (Physically Based Rendering) materials, HDRI (high dynamic range image) lighting, custom shader pipelines, and so on. We're currently pushing into realtime ray tracing, which is starting to look promising!",
"You dont need lots of polygons to achieve nice results. You can turn a cube in a perfect sphere with shaders. Or have realistic 3D brick wall with depth on a flat plane. What a good engine needs is efficiency and ease of use for these functions. Good and efficient way of calculating light. You could draw trillions of polygons at ease, but it doesn't matter unless you can use that surface to do other things with or calculate behavior of light."
],
"score": [
22,
4,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
in0on5 | How can video files as big as 26MB (for example) be compressed all the way down to 16MB - almost half its size - without reducing video quality? Are computers naturally not conservative with their space? | I've just recorded a 5min pitch video for my business which I'm trying to send to my co-founder over the internet. I need to compress the file to send it over either email or Whatsapp because it's too big (26MB). A quick and nice online compression site (Free Convert) compressed my file down to 16MB! Almost half its size! How is this possible? The video looks pretty much the same! | Technology | explainlikeimfive | {
"a_id": [
"g44blmg",
"g46f3mc",
"g44fvfu"
],
"text": [
"> Are computers naturally not conservative with their space? Sort of, yeah. That said, if your 5 minute video was 26MB, then it certainly was already compressed. An uncompressed video would be much, much, much larger. As is, the website just found a way to compress it even better (and unless you specified a lossless conversion, it probably did lose some details in doing so, likely this is where most of the data went). At the end of the day, compression can be complicated. There are so many ways to try to compress a file, and the best one will be heavily dependent on what you've actually recorded. Compression will take advantage of patterns in your data. Patterns are an opportunity to prevent duplicating information. If your video has the same image for a few seconds, there's no reason to copy that image hundreds of times. Instead, we can copy it once and specify how long to display that image. But if your video *is* constantly changing, then that extra bookkeeping will make your file larger. So there can't be just one \"best\" compression algorithm (and programs will handle different file in different ways). To add to all this, there's an efficiency vs speed calculation. 26MB isn't very much data, and compressing takes time. If it saved you 3 seconds to export it as 26MB, then it's probably worthwhile to do so until you need to make the file smaller. Compression's a game of tradeoffs. Speed vs efficiency vs fidelity, and modern computers are very good at tweaking these sliders so that it's seamless to the user, but sometimes it gets them wrong.",
"I've once downloaded a 150MB zip file that unpacked to a 3.5GB installer. Still no clue, what sorcery was at work there O_o",
"There’s a lot of stuff the website may have done. Yes, some algorithms compress better than others so it’s possible the website just used a different one. It’s also possible that the website just reduced the resolution so it looks the same on your phone but it would look worse on a bigger screen like your computer. When you say “without reducing video quality” you need to understand that video quality can be reduced without being too noticeable while already having a huge impact on file size."
],
"score": [
18,
3,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
in1j24 | why is it not allowed to use special characters in a filename? | Back in the day I guess those characters served a different purpose as well but shouldn't that have been fixed by now? | Technology | explainlikeimfive | {
"a_id": [
"g44jh15",
"g4524p4",
"g44j2z0",
"g450o54"
],
"text": [
"They absolutely serve a purpose now too, / \\”: and other characters are used in file paths which pretty much all programs use to access field, if suddenly they changed how file paths work, none of those programs would work anymore For the other part Windows literally allows emojis in file names",
"Many of those characters still serve the purpose they did 40 years ago. While it may not look like it modern operating systems are based on and have inherited many characteristics of their predecessors. Today everything you do is done with a GUI, but deep down your computer acts with the same logic as its ancestors which had nothing but the command line. In those days you worked with programs and files by simply typing the name of the program followed by the name of the file it was supposed to work on. For example: edit mytext.txt Would open the file name mytext.txt in a texteditor. If you wanted to open a file in a specific directory you would need to type something like: program /folder/folder2/file.ext This would open the file name file.ext in the folder named folder2 inside the folder name folder. The character \"/\" was used to tell the computer when the name of a folder ended. If you allowed the character inside of the names of folders and files it would get confusing very fast and you would have no good way to tell apart a file name \"fi/le.ext\" from a file name \"le.ext\" inside a folder name \"fi\". Other forbidden characters served and still serve similar functions. characters like $ and * originally worked as placeholders is DOS, while characters like > and | were used to tell DOS what to do with the result of the program they just executed. The same logic that applied decades ago still does. While it might be possible to create a new OS that would not have such a legacy this would mean that all the program written in the past decades would no longer work on it. Microsoft is and has always been very much in favor of erring on the side of caution with these things. They would prefer not to let users shoot themselves in their own foot and to keep things consistent because developers are users too. Linux for example has similar issues but they do allow users to actually use a number of characters in file and folder names that will break many command line scripts and programs. Linux will happily load your gun for you if you want to shoot yourself in your own foot. It is a different design philosophy. MS are very much in favor of playing it safe. For a good example of this try to create a file simply named \"con\" or \"nul\" or \"PRT\" in a modern windows. It doesn't matter if you capitalize any of those letters. It also doesn't matter if you give it an extension like \"\"Nul.txt\" or where you create those files. This all doesn't matter because the version of the OS from which those restrictions are inherited didn't support things like folders or extension yet and didn't support making a difference between a file name \"a\" and one named \"A\". Engineers could have at any point in the last few decades said that only the NUL in a specific directory would work as a NULL device and everywhere else the name was okay to use f something else, but they didn't because they thought that there were programs that might rely on things working the way they were, so even in the newest version of Windows things are kept the way they were in the early 80s for compatibility reasons.",
"It depends on the OS in general, but it's a more 'better safe than sorry' type of thing when you save a file in one OS and then it's opened in another. The best way to explain it why in the first place, MS-DOS (for example) uses those special characters for various commands. If one was the save a file with a special character, it would cause some problems. This continued to carry over once operating systems evolved beyond just using the command line into GUI and UI elements, but programs still heavily rely on command line syntax in order to at least function.",
"There still are plenty of characters that serve special purpose. Like slash(/ or \\ depending on your OS) telling the system that what preceded was folder name, and next you're supposed to look in that folder for this folder or file that follows. In general it's a good practice to avoid using any special characters in any major OS in your filenames. Depending on your system you might be able to circumvent different restrictions but it's all extra work that very likely is not accomplishing much for you. When you have the option to protect future you from frustration and pointless work, do so. Use safe characters for filenames."
],
"score": [
11,
4,
3,
3
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
in6h5r | How exactly do SIM cards work? | Let's say I have a Galaxy S8 and I want to unlock it because I'll be teaching in Thailand. I use Sprint but they don't really explain the purpose of unlocking your phone, nor do they explain the purpose of using a foreign SIM card. Is it better to use Sprint Global Roaming? Do I need a Thai SIM card to do that? Do I need a foreign SIM card at all? If I get a foreign SIM card do I need to get a new carrier or am I still using my previous carrier? I have no idea what a SIM card even is and I can't seem to find a single person that can explain it or its purpose. | Technology | explainlikeimfive | {
"a_id": [
"g45hz7g",
"g45j8bz"
],
"text": [
"Think of a SIM card as a username/password to authenticate with a particular carrier. Pull out the current one and pop in a new one, and assuming your phone is unlocked, you will now be using that carrier's service. Alternatively you can just use international roaming on your home country's carrier assuming it's offered (and using the home carrier's SIM card), but it often can be quite expensive, especially for longer stays or heavy users.",
"The SIM card is the thing that tells the mobile phone network who you are, what your phone number is, and, basically, who you're paying for cellular service. It's how the network you're actually connected to knows 1) whether to serve you and at all, 2) which phone calls/messages to send to you, and 3) who and how to charge for serving you. You do not need a foreign SIM card to go to a foreign country, at least form a technical standpoint. You just need a phone with the right kinds of radios to connect to the networks there...not all phones have the right hardware for all networks. Thailand appears to have many providers with many technologies, so you're probably good on that front. You do need a SIM card that at least one Thai network will talk to \\*and serve\\*. This is where, for example, having Sprint Global Roaming comes in. When you first connect to the Thai network it asks your phone \"Who are you?\" and your phone will reply, using the data on your SIM chip, \"I'm phone number XYZ and I belong to Sprint.\" The Thai network asks Sprint, \"Are you gonna pay for this phone?\" and Sprint replies with, \"Yep, he's got global roaming, go ahead.\" You connect to the Thai network and away you go. In the backend, there's some business agreement between the Thai network and Sprint to reconcile the bills. If you get a foreign SIM card you're switching carriers...your phone literally doesn't know it \"belongs\" to Sprint anymore. You'd have a new phone number, presumably Thai, on a new carrier with a new billing plan. That's why the phone needs to be unlocked...unless Sprint configures your phone correctly, the phone won't accept a SIM from any carrier other than Sprint. This is really common with large carriers because they've rolled the cost of your phone into your payment plan and they don't want your phone walking away before you paid for it. This is also why phones you purchase outright, not from a carrier, both cost more and come unlocked. Think of the SIM card as the hardware containing your cell phone contract; it's how all the cell systems know who you are and how to handle you. That's why SIM cards from from the carriers."
],
"score": [
5,
4
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
in6n8i | Why do guitar rock stars in arenas have VERY loud and elaborate amplifiers, when they are just being received by the soundboard via a microphone? | So, some of the cheapest guitar amplifiers that you can get cost < $100 and can produce MUCH more volume than my voice box can, but microphones work just as well for singers? And I am not talking about amplification to the mains. I understand that the sound coming OUT from the board needs to be heavily amplified to fill an arena. But the sound coming IN needs to be no louder than a human voice, but that is not what you see at concerts. Explain Like I'm Five! | Technology | explainlikeimfive | {
"a_id": [
"g45seb4",
"g45jthw"
],
"text": [
"Sometimes those stacks of amps are for show and actually not on or even real. However, sometimes guitarists do have a real amp on stage and mic'ed because they prefer the sound/tone of that particular amp. Guitarists are picky about tone and often don't like direct guitar - > digital interface.",
"It's not clear to me which hardware you're referring to as being a very loud and elaborate amplifier. You have a simple microphone picking up voice and instruments, an equally simple pickup on electric instruments that's functionally the same as a microphone in, that all feeds to the mixing board, great big amplifiers boost that to feed the mains. In order to play properly, every musician needs to hear what they, and the rest of the band, sound like in real time. In a small setting where they can hear the mains directly that might be fine, but in an arena or other large setting where the main speaker stacks are far from, and directed away from, the musicians they don't have any good way to hear themselves or their peers without delay/distortion/reverb, so you often have extra speakers near the musicians called \"monitors\". These are also fed from the soundboard but are there for the musicians, not the audience. Are you talking about the monitors?"
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
in7l6z | Why does Eco mode take twice as long as normal mode on Dishwasher and Washing Machine. How is that Eco? | Technology | explainlikeimfive | {
"a_id": [
"g45q1ob",
"g45pvo3",
"g45zfc0"
],
"text": [
"You're trading time for energy, and letting the water do it's thing by soaking. If you want to clean things quickly you pump a lot of hot water around really fast. The best example of this is restaurant dish washers, which cycle in 60-90 seconds but use super hot water and ludicrously powerful jets. An alternative is to use less powerful jets and less hot water, but let it soak into the food a lot more. The best example of this is when you have a pot that's horribly encrusted and so you fill it with water and let it soak on the counter for hours and it just wipes clean nicely. But it takes longer. The second way takes way less total energy, but it's slow.",
"It uses less water, normally. Imagine washing dishes/clothes with a dribble of water vs a strong spray. The dribble takes much longer to move the dirt, but the strong spray needs lots of water.",
"In a similar way, driving at 90mph will get you to your destination faster but will be much less efficient than driving at 50. The end result is the same, but going slowly uses up less fuel. Washing with a smaller amount of water at a lower temperature will take longer than spraying jets of hot water, but will use up a lot less water and less power too."
],
"score": [
10,
9,
7
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
in7n1e | How do password managers work? | I understand that they generate and store strong passwords for all of your sites and that you just remember one, strong password to access them all. But what I'm wondering is how it works if you are using someone else's computer and want to, for example, check you email? I know the passwords can be stored in the cloud or locally. If they are local, then obviously there is no way of doing it. But if they are in the cloud how would you use the password manager? | Technology | explainlikeimfive | {
"a_id": [
"g45q2x4",
"g45r35m"
],
"text": [
"I think the answer is they don't do anything special and you're not missing anything. Either you go to the password managers website and get your password, or you open the app on your phone and get it. Or, if you trust the device to a good extent you could install the software. But there's no magic here - you need to get to your password manager somehow. If it's not cloud based and you don't have it with you (eg. On a memory stick) then you're stuck!",
"\"In the cloud\" just means someone else's servers. They hold your (encrypted) passwords on a server online. You log into their website with a password. (or through an app, or through a browser plug-in, it doesn't really matter). They send you the big pile of all your passwords. You must trust the computer you are entering in your password to. It could A) have a keylogger between the keyboard and the computer. B) Have a man-in-the-middle front end to the real password manager. C) do some real shenanigans with retaining memory and not securely flushing it so that people can later extract your password or anything else you accessed or used. D) Probably some vectors I'm forgetting about, security is hard. But you're trusting your keys to the hardware and software you punching it into. If the password to log into the site (app/whatnot) is the same as the one decrypting your passwords, you must trust the password manager. There are ways to take in log-in credentials without seeing what user's passwords are. Client-side code. But you're trusting the webpage to do that. If they decided not to, then they could easily get the password that unlocks everything."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
in7snl | How does a GPS work? | Technology | explainlikeimfive | {
"a_id": [
"g45rlrh"
],
"text": [
"Each satellite broadcasts its current position and current time. This is picked up by your GPS device, with its time slightly out if sync with that of the satellite because the signal travels at the speed of light and therefore some time passes between the sat sending and gps receiving . Because of this difference and knowing what the speed of light is, the gps can calculate its distance to the satellite. If it can figure this out for at least four satellites, it can triangulate its location."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
in9htg | Why do people make their axes razor sharp? Doesn't that make the tip thinner and more prone to chips and damage? | Technology | explainlikeimfive | {
"a_id": [
"g46fskx",
"g463qbh",
"g466966",
"g47aace",
"g46cpvo"
],
"text": [
"The YouTube videos about \"axe so sharp I can shave with it\" are mostly about showing off their sharpening skillz. Axes and picks rely more on impact and wedge effect than on sharpness. You can give them a fine edge, but under normal use they won't benefit much from it and the edge won't hold up long.",
"Yes it does. It’s a trade off. But yes the sharper you make the edge, the more fragile the edge becomes.",
"This would only matter if you were using the axe for combat or to chop through chains or cables, etc. In the latter case the axe is likely to be galvanised with some material to strengthen the cutting edge. For cutting wood it's not really an issue since wood is soft, but you shouldn't be sharpening a woodcutting axe to a razor edge anyway because it doesn't add anything to the strength of the tool.",
"Splitting cut lengths with the grain rarely requires sharpness, a sharp axe will sink into the wood, and may be difficult to remove for the next strike. Cross-cuts, like when cutting down a tree, or limbing it after it's down, a sharp axe is MUCH better. A cross-cut with an axe is a V-shaped notch, where the axe slices across the grain obliquely in one direction, then the axe is used on the other side of the V to cut the grain on the other end, releasing a chunk of wood. Repeat until there is less wood than is necessary to hold the tree together. Speaking crossly to the tree may help separate it from it's other half, but will result in hard feelings on both sides and is best avoided for most deciduous flora, therefore a gentle persuading tap with the axe in just the right place is the most effective solution employed by the best lumberjacks.",
"The only time you need a razor sharp axe is in competitions. Where wear isn't an issue. Most people don't bother to make it super sharp, because of the risk of damage."
],
"score": [
15,
8,
7,
6,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
in9n0a | Why does microphone feedback get higher and not just repeat or get lower? | Technology | explainlikeimfive | {
"a_id": [
"g465sf8"
],
"text": [
"Answer: It's a positive feedback loop. Let's say the initial noise was at volume X. The microphone hears it and then it's amplified by the speaker to X+ the amplification. And the microphone hears it again. But now it doesn't hear X. It hears X + the amplification. Let's say the amplification value is A. So the mic hears X+A. Now this is amplified by the speaker to X+2A. And now the microphone hears it. And it is amplified again to X+3A. and so on. This will keep happening and get louder and louder unless the loop is broken. The numbers I threw up there are just examples to illustrate a point. The amplification isn't really linear."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
inf884 | How does factory reset work(router)? | Technology | explainlikeimfive | {
"a_id": [
"g478b0s"
],
"text": [
"the bios is installed on a chip and if you reset to factory settings it just re-installs itself as if you just bought it."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
infz0p | If the Pro grade mobile sector has better hardware than a nintendo switch or older consoles, why do mobile games still look so bad in comparison to graphics from 10 years ago? | Technology | explainlikeimfive | {
"a_id": [
"g47cmf0"
],
"text": [
"They dont put the money into developing a better game/wider audience aiming for people with lower end devices. Mobile games generally are something you play for a short time then get over, and no one is paying console prices for a mobile game. So they dont make as much initial money, so they dont spend as much on the game."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ingo0n | How do actual humans fail the reCAPTCHA test? | Technology | explainlikeimfive | {
"a_id": [
"g47j095"
],
"text": [
"This depends what you mean by “fail”. The test you see - where you’re asked to identify squares with fire hydrants or what have you - is the backup test. The primary test happens when you click the “I am not a robot” button. When you click, CAPTCHA software performs an analysis of your activity. This is mostly confined to what you’ve been doing on the web site in question - what pages you’ve visited, how long you spent on them, possibly which specific links you clicked, how you’ve moved the mouse while on the same screen and so on. (Until recently it may have also looked at your recent browsing via third-party tracking cookies, but these are now blocked by default in many web browsers - thanks to u/my_fifth_new_account for updating me on this!) The CAPTCHA analyses all this stuff to see if it seems like normal human-on-the-Internet behaviour. These are things a bot (a software robot; a computer program which interacts with other software using the bits normally used by humans) finds it hard to fake, and doing so would slow it down to human speeds, making it much less efficient. If that process doesn’t work - maybe because you happen to be visiting the web site directly in a new browser window instead of via clicking links etc, or more likely because the software can’t see those details because of your security settings, then you “fail” the initial test and get the traditional image puzzle. You might also “fail” that - but they have to be hard on purpose, because the information in many of them is used to train bots which then get good enough to solve them on their own. But often getting the answer wrong is a good sign that you’re human - and how long it takes you to attempt the test, and the way in which you try, are just as important to the CAPTCHA software deciding if you are human. So a human might fail the test and be marked as a potential bot if their browser activity is protected by security or they behave very efficiently, and then solve the puzzle quickly and precisely like a computer program might."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ini2pr | How does the Google maps timeline know what kind of transportation I took? | Technology | explainlikeimfive | {
"a_id": [
"g47poha"
],
"text": [
"Android OS has a built-in \"activity recognition\" feature that detects how you're moving. Apps like Google Maps can ask the OS for that information. How the OS detects your mode of transport is a bit complex. It reads a whole bunch of sensors to guesstimate what you're doing. If the bluetooth is paired up with a car speaker and the GPS shows you're moving fast, then the OS determines with high confidence that you must be driving. Or if the accelerometer says the phone is constantly bobbing up and down and the GPS says you're moving too fast to be walking, then you're probably riding a bike. That sort of thing. If you used public transport, then it's easy to work out just looking at where you stopped and how fast you travelled and the exact line you followed and a bunch of other things. The engineering behind that feature is actually remarkable."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
ini4zq | How do people hack? | I don't need detailed instructions, I have no interest in doing it, I'm just curious. I'd just like the basics. Like do you just type in a code or something? | Technology | explainlikeimfive | {
"a_id": [
"g47pkko"
],
"text": [
"A lot of hacking also involves social skills. Stuff like calling a business and convincing someone you're an outside contractor that needs a password."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
inibch | How can you get for example 10kV out of a normal 230V plug? | Technology | explainlikeimfive | {
"a_id": [
"g47q279"
],
"text": [
"Theres a component called a transformer. It basically consists of two coils of wire around two cores. The current is transferred from one coil to the other through electromagnetism. The number of turns in each coil is calculated to step up voltage. Simplified E.g. 5 coils on input coil, 10 coils on output coil, 2x Voltage It's been a while since I did electromagnetism, so someome else could step in on this point if I get it wrong: the thing that makes this difficult to believe is that it sounds like you get power from nothing. The extra voltage comes at the expense of current. The current slows down when the voltage is ramped up."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
injhgq | How do manufacturers make computer hardware do something when visually they are just pieces of metal and other materials? | Technology | explainlikeimfive | {
"a_id": [
"g47vwnd",
"g47w57q",
"g483pz1",
"g47zrm9"
],
"text": [
"Electricity is not visible to you is how. This is like asking how old school clocks work because they are visibly just pieces of metal. The structure of PC components is incredibly complex, which allows them to manipulate electricity in useful ways. It's just not evident to you at first glance. [This is how you see a 6502CPU with your mammalian Eyeball Mk.1]( URL_0 ) [This is how it looks under a microscope without the casing]( URL_1 ) [Red square zoomed in]( URL_2 ) [A few components labeled]( URL_3 )",
"The large picture is too complex you can understand the forrest. Stand small with a single tree. You need to look up logic gates first how they work then how they are made from transistors. Everything else scales up from there. An analog of what a computer you can use is a glorified calculator. It takes input from a user and performs an operation. Also it isn't a bunch of pieces but an organized complex system. Your body isn't a bunch of chemicals after all, being alive is much more than amino acids, proteins and carbon.",
"A very high level explanation is that a computer is just a complicated marble run for electricity. You put electricity into it (to power it and also to input data e.g. a keyboard) and it outputs the “result” as current you connect to output devices, allowing you to interact with it. Inside this marble run, there are counters, pointers, and scratch pads to store partial results (physically these are just circuits that can be set to high or low current and will stay that way). Calculations are carried out on a very low level: multiplying 4 x 5 would consist of a piece of code / pattern of current (at this level they’re the same) that added 4 to some scratch pad (look up binary adders for details on the circuit), and repeated itself until its loop counter hit 5. You can see how at this point it’s just a matter of packing in more memory and circuitry to do faster and more interesting things than multiple a number (although let’s not forget how revolutionary that was mere decades ago). Ah but there is the challenge of abstraction. How do you program high level concepts like a game? Do you really have to break it down into bits, counters and loops and all that elementary stuff? That’s where programming languages come in. Programming at that low level is certainly possible and used to be common, it’s called assembly programming. But because it’s very tedious, we’ve built higher level languages that allow us to write higher level concepts. This is than translated into code the processor can understand.",
"A lot of logic gates. Like a fucking shitload! These Logic gates take an input of electricity and turn it into an output of electricity. At its most basic level, you either DO HAVE electricity flowing, or you DONT HAVE it flowing. You can then turn this into Binary (DO HAVE = 1, DONT HAVE = 0), then use the binary to tell the computer what to do."
],
"score": [
17,
8,
6,
5
],
"text_urls": [
[
"https://upload.wikimedia.org/wikipedia/commons/4/49/MOS_6502AD_4585_top.jpg",
"http://static.righto.com/images/6502_overflow/outline-s400.png",
"http://static.righto.com/images/6502_overflow/metal_crop-s400.png",
"http://static.righto.com/images/6502_overflow/schematic_layout-s400.png"
],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
injve3 | Why is code THE language that computers can understand - is there not a code for the code? | Sorry if I worded this badly - what I'm trying to say is: How come the way code manifests itself is the way computers are able to read it, rather than any other way? | Technology | explainlikeimfive | {
"a_id": [
"g47y31a",
"g47yrzb",
"g47y4z4"
],
"text": [
"The computer actually doesn't understand the code. The code is for us, but each of those words or terms in the 'Code' language you're using translates to something else until ultimately it's simply a set of instructions that are only 1s and 0s So when we type in like PRINT \"Hello World\" that's kind of for us. It's then essentially translated to 1000101011010111010100110100101111001011010011010101010100101001 or whatever and that's fed to the actual chip The only thing a CPU really understands is the instruction to turn a transistor on or off. But a complex series of turning those transistors on and off and using logic gates can make it do calculations and produce a result that then gets translated to something we understand.",
"There are many different languages that you can write code in (C, Python, JavaScript to name but a few), but all of these are converted into what's known as \"machine code\". Machine code is the raw binary of the computer. It's tells the CPU exactly what to do in the simplest ways possible. The CPU knows what to do with this code because the instructions to read it are physically built in. A CPU is just some tightly packed electronics, and we can create electronics that do addition, subtraction, multiplication etc on binary values. So when the machine code tells the CPU to add, it activates just the right electronics so that only the \"add\" part of the CPU gets used.",
"Define \"code\". The only thing \"computers can understand\", speaking of modern PCs, are instructions. They are hard-coded to understand a limited set of very specific instructions, like \"sum this and this\" or \"next instruction you have to do is this one\". Every instructions is mapped to an unique number. Then speaking to \"the code\" normally people refers to. Well, no, computers can't directly understand that. What happens in the background is that it gets translated into numbers by an algorithm (a \"program\") that the CPU can understand."
],
"score": [
16,
5,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
inkm1h | What is Kubernetes? | Hello, I am writing an assignment about the usage of Kubernetes. I am really struggeling to understand what Kubernetes actually is, even though I have read a lot of articles online. I am not that knowledgeable on that field, so a lot of the stuff online is going over my head. Please help, Sincerly distressed student | Technology | explainlikeimfive | {
"a_id": [
"g48unro"
],
"text": [
"Say you just invented magic oil-detecting software. Exxon wants to buy your magic oil-detecting software, but you would rather sell your software as a service, so that you can also sell use of it to all the other oil companies in the world. You're worried, because if you hand over a copy of the software to Exxon, you'll lose a lot of control over it. They might use it more than they're allowed, or copy it, or even reverse engineer it to make their own magic oil-detecting software. So instead of just handing over the software, you put your software on a virtual computer in a cloud and let your customer use the software through that computer (but they don't have access to anything else.) Now they can use your software from anywhere, and you can see exactly how much they use your software (and charge them accordingly) and they never have access to the raw executable. This process is called \"containerization.\" Kubernetes is a popular system that allows people to set up and deploy these so called \"containers\" for their software. In addition to digital-rights-management, containers are also nice because they make the operating system not matter so much. If you wrote your software for Linux, but your customer only uses Windows, that's no longer a problem. You also can set up different containers to talk to each other. So if you invented magic oil-detecting software, and also invented magic oil-drilling software, you can use Kubernetes to get the two \"containers\" to talk to each other. This is great in the real world, when a salesman from a giant company like Microsoft rolls up to another giant company like Walmart and starts making a deal. The customer can pick and choose what services they want to buy, and Microsoft can ensure that the system will all run smooth as cocoa butter."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
inq5hu | why does Nintendo use cartridge based system while PlayStation and Xbox use disks. | Technology | explainlikeimfive | {
"a_id": [
"g495wut",
"g495rsa",
"g49c1t4"
],
"text": [
"Cartridges are harder to copy. But let's not forget that the Wii and Wiiu both used disks. I imagine they went back to a \"cartridge\" actually more like a memory card now for the switch because of size and power consumption.",
"A bit of history; Cartridges for a very long time were the standard go-to because optical discs didn't exist. We're talking like, back in the Atari and NES days. There were some disc based options out there, but they were mostly involving magnetic (floppy) discs, and usually had some limitations on how big they could make a game before having to include extra (floppy) discs. Eventually some folks invented CD's and that made storage space go from 16MB-32MB on a cartridge, skyrocketing up to around 700MB on a standard CD. Meanwhile the 'best' Nintendo could offer was up to 64MB for an N64 cartridge. At the time, storage space was a limiting factor in how much \"game\" they could actually put on the cart, and why several developers chose to go to other consoles that were embracing bigger storage media. Fast forward a couple decades, and in the modern era, we've got SD cards and BluRay. BluRay is itself a Sony-owned invention, or at least they were heavily involved in developing it - but the highest BluRays tend to go in terms of storage is around 50GB (15-30GB is much more common). Meanwhile, SD cards can pretty easily go up to 64GB and 128GB. Basically we're on the verge of the standard going back to cartridge based consoles. ;; As for why; Sony and 8 other electronics companies are responsible for developing Blu-Ray. Which means Sony has a bit of conflict of interest going on there; they want to encourage BluRay as a standard because they've already invested in it. Why not include a BluRay drive in their new console? That's on top of how PS2's were capable of playing DVD's - as a company, they've been developing their consoles to be more than just a gaming machine for the last 20 years. XBox and Microsoft entered the console market, and have felt the need to compete with Sony in terms of making a home entertainment console that could do more than just play video games. Thus they include a disc drive that can play optical discs. And then we have Nintendo, who never got on the band-wagon of making consoles that did anything other than play games. Nintendo doesn't really have an interest in making their consoles play DVD's or BluRays. That has meant Nintendo has some freedom apart from Sony or Microsoft in terms of how they actually package the game - they aren't bound by a conflict of interest, internally, to also support the optical disc formats, and they can pick whatever medium they want that will meet their design standards. They just get a little bonus of not having to pay Sony (or the other 8 companies) a licensing fee to use their patented bluray format disc drive when building a new console.",
"It's like comparing a decent SD card or flash drive to a Blu-Ray drive on your PC. Random I/O and non-sequential reads are much faster on the flash storage. Carts have the possibility of saving data on them, though that's not much of a point any longer since all consoles now save data to the console's internal storage or even to the cloud now. It was a bigger deal in the past. A cart will be more durable, even though Blu-Rays are scratch resistant. Unless the cart's board breaks or the case breaks completely in half it'll still work with some surface damage. It takes significantly less power to use a cartridge than an optical disc, too. That, and moving a spinning disc can easily cause it to wobble and scratch itself against the inside of the drive, so cartridges are ideal for portable systems. As far as cost per GB of storage, optical discs are still king. However, flash storage is always slowly dropping in price and increasing in speed, so it's catching up. IIRC Switch carts are 32 GB, while Blu-Rays discs can be 25-50 GB. Cost in general is higher for cartridges since anyone looking to make them has to buy new manufacturing tools to make them, while Blu-Ray discs are already being made in mass production (they only need a master disc made, I believe)."
],
"score": [
9,
8,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
intkit | why are we going back to capsules for manned space flight? | I would have thought after the space shuttle we would move on the another space plane like the x-33 or dreamchaser. Why did we go back to capsules? | Technology | explainlikeimfive | {
"a_id": [
"g49mwtr",
"g49n0xe"
],
"text": [
"Capsules are the most efficient way to get people and things into space. They don't take up any more space or weight than they need to, and fit nicely on top of a rocket in an aerodynamic way. Airplane based designs are much much heavier, and almost all of that extra weight is purely so it can function as an aircraft in the atmosphere which is exactly the place where we don't spend much time, so it's extra useless weight 99% of the time, and extra useless weight is the mortal enemy of rockets. It's perfectly fine to land under parachute in the ocean and get picked up by a boat. It's not that much more helpful to land on a runway, especially when it means you're lugging around a whole airplane on your back the whole time to facilitate that goal.",
"The Space Shuttle was a series of compromises It was designed to move people to orbit, move large satellites to orbit, and potentially bring a satellite back to Earth! That last one is what really did it in. The Intelligence agencies wanted the Space Shuttle to be able to pick up one of their Keyhole Satellites (which Hubble was based off) and bring it back down to Earth if needed. This results in a very large craft that ends up being heavy so it can withstand a heavy reentry, but also increases the size of the rocket you need to get it up there and reduces the payload it can carry into orbit. You're better off having one craft for each job. A Crew Dragon for moving people is only good at moving people but that reduces the complexity and cost for any mission where you only need to move people. A Cargo Dragon is really good for moving cargo which reduces costs for the majority of missions where you just want to send cargo up and maybe bring a really small amount back down. And if you just want to put a satellite into orbit, why are you sending life support along with it when you could just launch it into its orbit on a basic rocket? The dream for the spaceplane was that we'd launch them, bring them back, refuel them, and send them back up, but engines during that era weren't built for quick reuse so they basically stripped all three engines off the shuttle and replaced them for each flight."
],
"score": [
8,
4
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
inu9md | My fire alarm goes off when there's smoke coming from the oven but the water sprinklers doesn't start. When do the sprinklers go off? | Technology | explainlikeimfive | {
"a_id": [
"g49wwpr",
"g49ql3h"
],
"text": [
"Are they made of wax now? I worked on fire detection and suppression systems back in the 90’s, the little coloured bulb was always made of glass. It contains a coloured liquid that boils at a certain temperature, different colours indicate the different temperatures that the liquid will boil at. You may in fact notice sprinklers with red bulbs, or green, or blue, etc. This allows sprinklers to be more sensitive in one area of a building, while less sensitive somewhere else. When the liquid in the sealed bulb boils, the pressure inside increases quickly and the glass breaks causing the glass bulb to fall out the sprinkler head. That glass bulb is typically holding a small metal disc that covers and seals the water outlet from the pipe, removal of the glass bulb holding the disc causes the water in the pipe to flow, (the tap just opened). The water that ‘was’ in that pipe was under pressure, not a lot of pressure, but enough that the sprinkler system can measure and look for sudden change, this will of course happen when the water starts flowing out of the pipe, and in response to that the sprinkler system will turn on an electric motor that will now push a LOT of water down those pipes under high pressure. Sprinkler systems are expensive, no one is going to install a sprinkler with just one or two sprinkler heads, a typical system will have 50 or more sprinklers covering a building. Due to the design of this system, only the bulbs that are sufficiently close enough to the fire to heat up, will open, conversely, bulbs that do not get hot enough, will not open, even if they are in the same room, only proximity to the fire (direct heat) will determine if they open or not. This prevents water damage in areas where there is no fire.",
"They go off based on heat. Most of them have what looks like a little red bar of plastic in the middle. When that melts, it starts the water."
],
"score": [
38,
30
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
io0li3 | What is the grey goo apocalypse | Technology | explainlikeimfive | {
"a_id": [
"g4atyo4",
"g4au9xz"
],
"text": [
"that's basically it, the idea that self-replicating robots could get out of control and \"eat\" all the biomass on earth. They don't have to be tiny necessarily. Think Horizon: zero dawn if you played that",
"\"Grey Goo\" refers to a hypothetical catastrophe in which, whether intentionally or otherwise, we deploy some kind of self-replicating machines (usually, yes, nanobots) whose replication is based on reassembling available matter. Given no stop condition, or a condition that breaks due to some unforeseen error, the idea is that these machines would simply continue to self-replicate. Because each one made would make *another* one in the next generation, the growth rate of the group would increase immensely (i.e. 1 nanobot makes another, then both of them make another each, and so on as 1 - > 2 - > 4 - > 8...). Because they must convert existing matter, this rapid growth results in the quick repurposing of everything on the planet (and, potentially, a large part of the planet itself)... including us."
],
"score": [
6,
6
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
io1g5v | What affect do power cuts really have on a computer? | If the computer is running and gets suddenly turned off by loss of power, what really happens? Is there damage that happens slowly or progressively over time or is it more of a risk that something might happen to the computer suddenly in any event? | Technology | explainlikeimfive | {
"a_id": [
"g4azlyc",
"g4az4b7"
],
"text": [
"Usually, nothing that bad happens. Starting up should fix most things that were cut short. The exception is when the computer is actively writing or changing data on the hard drive when the power is cut; then the written data will be incomplete. That’s how data can get corrupted. If it’s a word/pdf/general data file that’s corrupted, that file is basically lost. The real bad issue is when this happens to system files that your computer uses to start up; then your PC may have issues start up.",
"Biggest issue is data corruption. Things that were in the process of being written to the hard drive but didn’t complete. Windows (or other OS) will make an attempt to fix it on reboot but it’s sort of a situation where it doesn’t know what it doesn’t know. Which is why you should never cut and paste, but copy and paste and then delete the source if you’re at risk of a power hit."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
io33nw | How do glasses work? | Technology | explainlikeimfive | {
"a_id": [
"g4b8xbz",
"g4b99qg",
"g4b9gox"
],
"text": [
"Glasses as in spectacles?? They are usually concave or convex depending on your problem (myopia or hypermetropia). Myopic people use concave lenses. The problem with myopia is that the light rays converge before reaching the retina. The image is sharp at the focal point and for a normal person the focal point is at the retina but in myopics the focal point is before the retina. So they have a distorted image. A Concave lens diverges the incoming light rays a bit before it hits the cornea and lens so that it when it converges it does so at the retina In the same way in hypermetropic people, the light rays converges at a point beyond the retina. A convex lens is used in this condition and it helps in converging the light rays further so that it properly focuses at the retina. There are also other conditions such as astigmatism, where the corneal thickness varies and the image is distorted and wavy, in such conditions a cylindrical lens is used to correct Hope this helps!!",
"Depending on your exact issue with vision, you may not be able to see objects close to you or at a distance. This is caused by an issue with the lens of your eye being unable to focus light effectively on your retina. If near-vision is a problem for you, this means your eyes focus light onto a point that is 'before' your retina. In this case, concave glasses which cause rays of light to diverge from each other, allows for light to be focused correctly on the retina by the lens of your eye. If far-vision is a problem, the lens focuses light on a point 'after' the retina. In this case, the glasses will be convex. The lens of your eye then finishes the job, and focuses light on the retina correctly. Bifocals work by having convex and concave lenses in different parts of the spectacles.",
"I'll try my best At the back of our eyes, there are nerves to receive light (what we see). That light goes through our eyes where there's a lens (the centermost circle of our eyes). What these lenses do is they take all the light that would otherwise go in a straight line, and bend them, so that they all focus onto one spot on the nerves. Normal eyes would have normal, properly working lenses, meaning the image/light going into the eyes would be properly focused. But some of us have abnormal ones (too thin, too thick, or damaged in other ways) and so the focus is off (too far backwards, to far forward from the nerves). When this happens, the nerves dont get focused images, so what we see arent focused. So eye doctors find out how much thinner or thicker it is compared to normal ones and prescribe you with glasses :D which are just bigger versions of the little lenses in our eyes. These bigger lenses are curved in whatever way the doctor sees fit and they pre-bend the light rays that would then pass through the abnormal eye lenses. The point is so that the focus goes back onto the nerves. Hope this helps, ama!"
],
"score": [
5,
3,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
io38vt | How are bits in the hardware of a computer built? | A giga byte is about 8 billion bits, but I can hardly imagine that people/machines build billions or trillions of little bits into my phone or a console, if so how is that possible? | Technology | explainlikeimfive | {
"a_id": [
"g4bah83"
],
"text": [
"Transistors on that scale are not \"buildt\", what happens is more comparable to printing. After all, a transistor (and by extension a computer chip) is basically just some layers of conductive, non-conductive and semi-conductive pathways on top of each other. If I recall correctly, one step is to first add a layer of copper to the chip, then shining a specific wavelength of light through a transperent \"map\" of the desired pathways onto the chip, and then introduciing gaseous acid to the chip surface. For some weird chemical effect, the parts of the copper layer that are illuminated are protected from the effects of the acid, therefore the acid eats away all the other copper, and you are left with a layer of copper pathways. The important part here is that the \"pathway map\" can be ridiculously complex and have billions of pathways, but this does not affect the duration or cost of this production step. Now, thats only one technique, and the different layers of the chip require different steps. But at no point in them does a machine manufacture billions of tiny elements one by one, or carve billions of grooves into some surface with a tiny drill."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
io3x6j | How does a record player work? | Technology | explainlikeimfive | {
"a_id": [
"g4bggcy"
],
"text": [
"Sound vibrates the air. The air vibrates a microphone. The microphone vibrates a coil of wire. The coil of wire vibrates an electrical current. The electrical current vibrates a cutting needle in a metal plate. The metal plate now has cuts that are shaped by the sound. The metal plate is used to make a plastic disc. The plastic disc vibrates the pick-up stylus. The pick-up stylus vibrates a coil of wire. The coil of wire makes a current. The current drives an amplifier. The amplifier drives a speaker. The speaker vibrates the air."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
io4ggu | How does ad blocker work and how does website know if we are using one? | Technology | explainlikeimfive | {
"a_id": [
"g4bfqw3"
],
"text": [
"The ad blocker has a list of rules on what page elements, JavaScript files and content servers to block. This includes rules like \"servers belonging to Annoying Ads Inc\" or \"in Mega News site and subpages, a specific element called top-ad-banner\" or \"All scripts on Mega News site's /eviltracker/ directory\". These are usually hand-made lists and are maintained by volunteers, because it takes effort to identify these things correctly and make sure you don't block too much or too little. Previously, it was also common to use some kind of heuristics (e.g. \"All images that are yay big are probably ad banners and should be blocked\") but those aren't that popular these days. The website can detect ad blockers by detecting if some particular page element is present or not. (Of course, nothing stops the ad blockers from blocking that kind of scripts, but hey.)"
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
io8xno | Barcodes. Who "assigns" them? When do you need to get them? Is there a "barcode register"? | Technology | explainlikeimfive | {
"a_id": [
"g4c7dms",
"g4ck1k7",
"g4ceyg8",
"g4c85mw"
],
"text": [
"Bar codes consist of a \"prefix\" that identifies the specific manufacturer and then an \"item number\", which identifies the exact item. There is a global registry of prefixes and you have to register and buy the prefix, but there's not a global directory of individual items. If you're running a grocery store, it's up to you to fill your cash register database with the bar code data from everything you're selling. That's why you can go into a store sometimes and the cashier scans your item and the register comes up with \"item not found\". Either it wasn't added or it was deleted somewhere along the way.",
"At their simplest barcodes are just numbers in a machine readable format. Anyone can create barcodes and use it for whatever purpose. Machines read barcodes by decoding the number and looking that number up in its database. Based on that it can action accordingly. For product barcodes in shops these will relate to their UPC code and these codes are managed by an international agency to ensure uniqueness. However the tills that use these codes will need the product added into the system to be able to read it. This record will be the stores info about the product including price, promotions, weight (for self service machines) and any other details they need. It can be used for stock counting to. Some barcodes can use letters too but again its still a case of looking up the product. Many companies will produce barcodes for there own purposes such as logistics where everything has a barcode (or 2)for Sortation. Again machines will either look up the number for routing or the label will have sort codes that simply layout part of the journey (i. E which depot its going to). For logistics often bags, cages, vans, depot doors, lorries and even planes have barcodes allowing an employee to scan an item and then scan what they are loading it into. Scanners will also log that they've seen an item and this info is used to provide tracking information to the customer. For couriers they will use a common barcode format (i.e code 128) and then lay out specific formats for this. Large customers can often generate their own barcodes within a specified range and then transfer that data to the courier.",
"Barcode is a font that's easy for a scanner to read, and usually when you see a barcode, it's the inventory ID of the item. You can create your own barcode system for anything if you wanted to, just using stickers, computer, printer. It is just a font. EDIT: [ here's a link ]( URL_0 ) Clearly there's some confusion in this thread, or just ppl who never applied a barcode system to anything before. You can write whatever in barcode, it's just a font that's very hard for human eyeballs to read, but very easy for a laser scanner to read. Mostly used to track and manage inventory.",
"Barcodes are all registered and administered by GS1 corporation. Vendors purchases big blocks of UPC code for the first few digits. The remaining digits are used for all products of that vendor"
],
"score": [
35,
7,
4,
3
],
"text_urls": [
[],
[],
[
"https://www.dafont.com/barcode-font.font"
],
[]
]
} | [
"url"
] | [
"url"
] |
|
ioe4j0 | In international football games on live tv, every country sees local ads on the billboard screens surrounding the field. How does this work? | When the camera zooms in, I clearly see pixels in the 'ad ribbon' surrounding the field, so the billboards look like physical (low res) screens to me. But how can screens show different ads for each country at the same time? Are they not screens? Sometimes I see projected ads next to the goals, and those clearly look like CGI because they 'glitch' when people walk past them, or look different depending on the camera angle. The ads in the long 'ribbon' look nothing like that and don't seem to glitch, ever. I'm trying to follow the game, but I can't, because of this questiong haunting me. Help? Edit: Example: URL_0 | Technology | explainlikeimfive | {
"a_id": [
"g4d83zn",
"g4da6oc",
"g4dr5yt"
],
"text": [
"Wait, are you telling me that if you turn on Premier League, La Liga or the World Cup you see country-specific ads on the billboard? Can you tell me what country you are from, what league you’re watching and what ads you are seeing?",
"~~I honestly have no idea what you are talking about (I live in the US and don't watch sports), but I have a couple guesses.~~ 1) Its possible that the displays simply show a solid blue or green screen (or maybe a marker, like a QR code) and then local channels superimpose their own advertisements over it. ~~2) it's also possible that they simply show local commercials from major population centers in the countries currently playing.~~ ~~Of course, neither could be true as well. If possible could you provide an example of what you mean? Is there like a video or image you could share? We might be able to get a better idea of what's going on if we can see exactly what you're talking about.~~ Edit: Found it! Basically the first one. It's called [virtual advertising]( URL_0 ).",
"It's actually not that exciting. There are real LEDscreens around the pitch. But the home team or the (in case of a tournament) Fifa/Uefa holds the sponsor rights. This is normally given to the sponsors of the hometeam or country and they sell this per minute to their sponsors. Sometimes these rights are sold commercially and it happens mostly with international friendlies that they use a simple trick. They sell the surrounding pitch but put the advertising of Team A on one side and Team B on the other side and then they use 2 cameras on opposite sides. The small advertisement next to the goal post is indeed called virtual advertisement and sometimes they do use a real carpet printed in perspective. When they use the virtual one they use an extra camera where they mount an extra lens with a virtual grid inside that consists of approximately 80 marking points. This way the CPU on the camera always knows when to virtual print the logo in the right spot. These logos need to be preset in the grid. So you can't see other logos on other channels unless they use multiple cameras."
],
"score": [
6,
3,
3
],
"text_urls": [
[],
[
"https://en.m.wikipedia.org/wiki/Virtual_advertising"
],
[]
]
} | [
"url"
] | [
"url"
] |
ioi5rq | how a headphone (or speaker) driver can produce multiple frequencies at 1 time | like how can an electromagnet alternate current at 2 different speeds? | Technology | explainlikeimfive | {
"a_id": [
"g4dzaei"
],
"text": [
"It doesn’t have to. When sound waves overlap, like waves on the ocean, They merge together if two peaks of the waves overlap they amplify, if a peak and a trough overlap they cancel each other out. This is called Construction Interference and Destructive interference respectively. So effectively, all these ways of vary amplitudes and frequencies all overlap each other and can effectively be combined into one really strange looking and kind of irregular wave. That combined wave is that the speakers copy and put out, so instead of the speaker shaking at two different frequencies at once, it actually shakes at a specific mix between both of them that to our ears sounds the same."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
ioj956 | how do touch screens work? | Technology | explainlikeimfive | {
"a_id": [
"g4e6fnh"
],
"text": [
"Your body is a big battery, when you touch the screen it detects the charge. The gloves either have a conductive coating on them or they are a bad enough insulator that the device still detects your finger"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
iojki8 | Why does including numbers and special characters in a password make it stronger if a hypothetical brute force hacker has no prior information about the composition of the password? | I've seen a lot of explanations for why including numbers and special characters in your password makes it stronger, and they all rely on the fact that adding them increases the number of possible combinations for a given password length. But a hypothetical brute force hacker has no way of knowing whether or not the password they're trying to figure out has both letters, numbers, and special characters or just letters. As long as the password could *potentially* include numbers and special characters, shouldn't all passwords of a given length be equally safe from brute force attacks? | Technology | explainlikeimfive | {
"a_id": [
"g4ecdqn",
"g4fwl8w"
],
"text": [
"Imagine you have a password lock, but it is only one character and can only be a 1 or a 0. Pretty easy to crack isn't it? There are only two possible combinations, you've got a 50/50 chance of guessing it on the first try. Now imagine the same one character password can be any number between 0 and 9. Guessing the password just got five times harder. If instead it can only be a letter between a and z, including capital letters, guessing becomes almost 50 times harder. Experts call the number of possible combinations a password could be the \"key space\" and the larger the key space is, the harder it is to crack. Computers can guess tens of thousands of passwords per second, so making things hard for a computer involves using the biggest possible key space you can. By using numbers 0-9, letters between aA and zZ and all the special characters found on most keyboards you have roughly 90 possible one character answers. Every additional character used multiplies the number of combinations. Example, with every character having 90 possible answers and two characters required is 90x90 or 8100 possible combinations. A three letter password would have 729,000 possible combinations. A 12 character password has BILLIONS of possible combinations. All of this assumes a user will use a random selection of passwords. In the real world though people prefer to use very simple passwords, often easily remembered phrases. Many hacking attempts start by running through the 100 or so very commonly used passwords. (As a former I.T. pro, the number of people using \"password123\" or \"LetMeIn\" is depressing) Forcing users to use at least one capital letter, one number and one special character is something of a compromise between the best practice and what actually works for humans.",
"The reason you force users to include non-alphanumeric characters is because most people will use weak passwords if given the chance. There's a reason why the most common passwords lists includes the word \"password\"."
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
iolbs3 | How does strafe jumping in video games work? | So I know that originally strafe jumping came from a bug in the Quake Engine, and it's why so many older games (CS, Quake 3, etc) have it. I also know the bug comes from the accelerate function, but I don't quite understand *how* it ends up building speed. Something with the wish direction getting combined with speed maybe? How does that happen? I'm not sure, any help explaining would be greatly appreciated!! | Technology | explainlikeimfive | {
"a_id": [
"g4el0kx"
],
"text": [
"There's a tendency in games to break a little bit from real life, and the two biggest things are counting the speed of things along different axis' separately and acceleration quirks. In that old strafe jump technique, you end up combining the acceleration of the strafe, the forward movement and the spin of your mouse all together, then jump to maintain it. If you think of it move simply though, a game where simple strafing is faster...it's Pythagorean theory basically. If I Hold forward I move at speed A, if I strafe sideways I strafe at speed B as well... then if I angle myself diagonally, the game happily lets me move at speed C... A\\^2+B\\^2=C\\^2 I move my 4 mph forward, my 3 mph sideways and end up at 5mph diagonally in the direction I really wanted to go. Then add acceleration and jumping to that too, it ends up with weird shit on top of that."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
iolkzq | Why are racing watches called racing watches? | They always come with a timer and chronographs. Do racers really look at and use their watches when going at high speed? | Technology | explainlikeimfive | {
"a_id": [
"g4elwyy",
"g4ellet"
],
"text": [
"It's less about looking at it but it's the ability to be a stopwatch or do split times and stuff, where you don't have to look at the time, but you can check it after. Also remember that term is from like the late 1800s and it's just still called that. No one would use a non-digital device for timing something fast these days where the 0.01 second matters.",
"I think it harkens back to the early days of motor racing, think 1920's or earlier. Guys would take their cars out to the test track and tinker with them, run a few laps, and these watches helped them with timing the test run. Then they would tinker some more, test some more, and repeat that until they were happy. And if you were the driver of a race car, you weren't always the owner or mechanic, so it's possible that one of those guys was standing on the sideline, watching the car going around the track and timing it."
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
iom92r | How do Smartbulbs work? | I've tried to Google it but theres just reviews about smartbulbs and I want to know the science behind them. How does the LED generate different colours, does it take up less power if the light is dim? What is inside a smartbulb etc TIA | Technology | explainlikeimfive | {
"a_id": [
"g4es6jn",
"g4eqk96"
],
"text": [
"There's essentially just an LED element, some kind of microcontroller, a wifi adapter (or bluetooth adapter), and a power supply (LED's don't run off 120V AC). Some bulbs (like the phillips hue) require a \"bridge.\" These bridges are what connects to your wifi/router, and then the bulbs just connect to the bridge. Either way its just to enable you to be able to communicate with the lights. The microcontroller has code on it to use the WiFi card to connect to your network, and then you use an app to confirm the lights are on the correct network and sign them in. There are usually 4 different LED elements - red, green, blue, and white. Any of the colors can be achieved by blending these three colors, and the amount of saturation can be controlled by adjusting the brightness of that color mix in tandem with the white. Because the power supply is stepping down the power from 120V to probably either 5V or 3.3V, and microcontrollers and LEDs don't use a ton of power, they will use way less power than a regular bulb. When you dim the LED's it will use slightly less power but with a micro and a wifi adapter it's likely not noticeable looking at power used by the bulb as a whole.",
"Circuitry allows the bulb to send power through different LED’s inside for different colors. They do use less power if dimmed but they already use so little that the difference is negligible."
],
"score": [
8,
4
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
ion9yd | If HTML5 is a markup language, how can it replace Flash? | Technology | explainlikeimfive | {
"a_id": [
"g4evovg"
],
"text": [
"The markup includes scripts, and those active scripts can do things that some websites have historically use Flash to do. There are so many security concerns with Flash that many are unwilling to use it."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
iop3au | How does 'brute forcing' work? | I've seen a lot of graphics showing how long it would take a hacker to brute force their way through a password. However, at least on every password protected service I use, there is a limit on how many incorrect passwords one can enter before they get locked out. | Technology | explainlikeimfive | {
"a_id": [
"g4f5x8t",
"g4f96i0"
],
"text": [
"When you create a password for a service, the service needs to create a copy of that password so that it actually knows what it is for the next time you log in to the service. When they do this, they *generally* store what is known as a hashed copy of your password. Hashing is a sort of one-way encryption: you give it a particular input, it will ALWAYS give you the same (jumbled) output. This makes it great for authentication. You put the same password back into the authentication screen, they hash it the same way they originally did, and compare it with the stored hash. If they’re the same, they let you in. A hacker just needs to get access to this hash (which is ridiculously easy, given most companies security practices are actually terrible). The hash is just a piece of information stored in a database server somewhere. Once they have the hash, they can brute force to their heart’s content. The limit only applies when you’re trying to authenticate through the authentication service.",
"When you enter your username and password into a login box, the website or the application or whatever calculates a hash with that username & password pair, and checks it against an authentication database on a server somewhere. If that hash exists on the database, it lets you in. But, as you've noted yourself, you can't brute force that because you'll get locked out. What you *can* brute force is that authentication database itself directly, without going through the servers of the website/application/whatever. But for that you need to have a copy of that database, which is surprisingly easy because a lot of people don't understand security. Once you have that copy, you can unleash the full processing power of a modern computer on the database. A semi-decent PC can try millions of passwords a second. Computers dedicated for this purpose can push 100+ billion passwords per second easily. Which sounds like a lot, but fortunately it's still hopelessly inadequate if you've picked yourself a secure password."
],
"score": [
8,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
iop76u | Why are more and more websites becoming minimalist? | Technology | explainlikeimfive | {
"a_id": [
"g4f6agp",
"g4ffjzz"
],
"text": [
"It's a clean look that makes things easier and more consistent (from a design perspective) when presenting sites both on mobile and desktop.",
"(Web-)developer here. There are a multitude of reasons for this. As others have already mentioned the popularity of mobile browsers has kind of pushed a cleaner design philosophy but also on mobile you don't want to use up too much data. Every little element, every color, every animation uses up a few KB on the page load. This increases data consumption and load times. Every few seconds of load you lose visitors (people are really impatient nowadays). Visually cluttered websites also convert worse (convert means generating profitable interactions for the website-owner, like sell stuff in a shop) so cleaner designs push that. Google actually takes that stuff into account so you want a clean and simple website to rank better. Nearly all Desktop Designs are just slightly enhanced mobile Designs on most websites. Making those clean, simple Websites is cheaper."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
ioq6kc | why does radiation destroy or interupt electronics? | I just finished Chernobyl(2019) and am really curious about it when it was mentioned. | Technology | explainlikeimfive | {
"a_id": [
"g4fc6di"
],
"text": [
"Ionizing radiation will generate a small electric charge when it hits an atom. So you will get small rouge charges going through the electronics. These will be amplified by the transistors used for the logic and cause it to send a signal where there should not be one. So a zero would become a one or a one would become a zero."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.