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cszjv9
How are computer chips with billions, or now trillions, of transistors made?
I just saw on r/tech that a chip with 1.2 trillion transistors was made. Surely, these aren’t made by hand, and I don’t understand how anything could make this chip, hence the post.
Technology
explainlikeimfive
{ "a_id": [ "exhqb2s" ], "text": [ "The general process is called photolithography. Basically you shine light through a stencil that hardens a chemical coating. The non hardend chemical (photo resist) gets washed away, and various chemical processes are used to add or remove layers different types of sili...
[ "url" ]
[ "url" ]
ct0fcm
New TVs boast the ability to display more colors. What colors can't a TV display?
New TV's are HDR, or high-dynamic range and they boast the ability to show 10 or 12 bit color. Once there are enough "bits", does that mean that they will be able to show every color? How many bits is enough? Or are there colors that TVs and computer monitors will never be able to show?
Technology
explainlikeimfive
{ "a_id": [ "exhtxmg" ], "text": [ "Theoretically, there is no number of bits which would be able to display \"all colors\". However, many TVs can already display PRACTICALLY all colors." ], "score": [ 4 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
ct19sh
Managing Human Waste
How do we manage human waste? On average a persons produces 145 kg of poop per year. That means that yearly we produce globally 1 billion tons of poop or 2,7 millon tons per day. So where is all this poop going to?
Technology
explainlikeimfive
{ "a_id": [ "exhz1s8", "exi67f5", "exi1h78", "exhzem2" ], "text": [ "In the developed world, sewage treatment plants filter out \"solids\" and decontaminate the water before discharging it. The discharged water won't kill you if you drink it, but it's still usually kinda dank. The dried solids...
[ "url" ]
[ "url" ]
ct2csy
What tricks are used to get the sense of scale and vastness in Open world Games.
I have played my share of open world games and recently started Assassins creed Odyssey which got me thinking. How can they make a world so vast when travelling on foot and yet, in comparison, so “small“ when travelling on horse or ship. While standing in the middle a village it feels huge but standing on a overlooking...
Technology
explainlikeimfive
{ "a_id": [ "exi5rsn", "exi8r4h" ], "text": [ "I think mostly with detail and mobility. Like as a person we don't get a nice 3rd person view which is much higher than a normal view. In a city you get to see more at once. Also we can't exactly climb buildings in an instant for a better vantage point. A...
[ "url" ]
[ "url" ]
ct5thm
why do CDs have to spin to be read? Why don’t solid drives have to spin to be read?
Technology
explainlikeimfive
{ "a_id": [ "exirxdr", "exircj2" ], "text": [ "The data of a CD is laid out in a spiral much like the groove of an old vinyl record. The read head scans the digital markings as the disc spins in order to read the data. Solid state drives are simply large banks of addressable memory. There is no disc, ...
[ "url" ]
[ "url" ]
ct6e7r
How can devices/phones constantly listen for "Hey Siri" (or Alexa, etc) without noticeable energy drain, despite feeding a neural network with constant microphone input would need lots of energy/cpu cyles?
Technology
explainlikeimfive
{ "a_id": [ "exj2gku", "exjangu", "exjm56d", "exjdm1a", "exji29k", "exjp5jp", "exjrg79" ], "text": [ "I’m not sure on the android side of things, but iPhones have a coprocessor (dubbed M9, M10, M11, and M12) that handle this task *specifically*, which allows for lower drain. It’s b...
[ "url" ]
[ "url" ]
ct6g76
How do search engines get results so quickly?
When I look something up on google or look up a name on Instagram I get results nearly immediately despite there being like billions of results for the search to look through. Even just making a search for a specific file on my laptop takes a while, so how do companies like these do it so fast?
Technology
explainlikeimfive
{ "a_id": [ "exixdvc", "exivgfz", "exjq9y4" ], "text": [ "Google has an army of computers that are constantly \"crawling\" the web in the background, 24 hours a day and analysing the information on each website. This is a slow and never ending process. They use the information to build up a databa...
[ "url" ]
[ "url" ]
ct6s5b
How do the cables that the Department of Transportation stretch across the road accurately measure traffic?
Technology
explainlikeimfive
{ "a_id": [ "exixv4c", "exj1loi" ], "text": [ "they are pressurized tubes and every time a car drives over the tube, the pressure shift on the tube flips a counter. You may have seen something similar to ring bells at gas stations or car repair shops to notify attendants to come.", "That tube, act...
[ "url" ]
[ "url" ]
ct79qi
Why is it so hard to port console games to PC and vice versa?
Technology
explainlikeimfive
{ "a_id": [ "exj0zzw" ], "text": [ "Because you literally have to rewrite the software to work on a new console if there doesn't already exist a way to play the game on the console. Just like your body has nerves, and bones and muscles etc. to make you work, a computer works much the same way. If you just...
[ "url" ]
[ "url" ]
ct7iy2
How do batteries charge faster than they discharge?
Technology
explainlikeimfive
{ "a_id": [ "exj4o85" ], "text": [ "Batteries have maximum charge and discharge rates. Offhand, I can't actually think of any rechargeable battery that has a maximum charge rate that is greater than its maximum discharge rate. So, the short answer is, they don't. All or almost all batteries \\*can\\* be s...
[ "url" ]
[ "url" ]
ctay2d
My hotel clock is apparently a new model & has two USB charging ports, one 2x the amps of the other. Why is this common, & why not just make both the higher amperage?
Technology
explainlikeimfive
{ "a_id": [ "exjqdec", "exjqrnm" ], "text": [ "A 2A + 1A duel charger requires a 3A power supply, and that's cheaper than the 4A power supply that a 2A + 2A duel charger would require. When your making 1 million charging clocks a $0.10 cheaper power supply is a savings of $100,000.", "Some devices...
[ "url" ]
[ "url" ]
ctbl7y
What makes the https protocol secure?
Technology
explainlikeimfive
{ "a_id": [ "exjuyyl" ], "text": [ "The 's' in https means secure. Jokes aside, https uses SSL/TLS encryption between your browser and the webserver. There are groups called Certificate Authorities (CAs) who exist to vouch for the identity of different websites. They use keypair cryptography (in which the...
[ "url" ]
[ "url" ]
ctbpjp
How does the ‘I’m not a robot” tick box reCaptcha determine whether I’m human or not? How good is it?
Technology
explainlikeimfive
{ "a_id": [ "exjvf3y", "exjvf2x" ], "text": [ "Before you ever see that checkbox they've already considered a bunch of stuff. Has your browser identified itself as a normal browser (as opposed to just being a script that's running with no graphics)? Have there been a bunch of requests from the same co...
[ "url" ]
[ "url" ]
ctchf2
How do people pirate windows keys and sell them for really cheap?
How do they get them in the first place.
Technology
explainlikeimfive
{ "a_id": [ "exk3no7" ], "text": [ "The main trick for this is breaking regional reselling rules. The price of windows varies greatly by country. These people buy a key whereever it is cheapest, and sell it on the internet. This is not against the law. It could be against the Terms of Service of Microsoft...
[ "url" ]
[ "url" ]
ctcsl1
How do video streaming services work?
I'm very much interested how Netflix (on-demand), and the WWE Network/NBA League Pass works. (Live and on-demand). How do they maintain the data? How do they stream it live or make it like a DVR (pause and rewind)?
Technology
explainlikeimfive
{ "a_id": [ "exk20ho" ], "text": [ "The same way that anything on the internet works, they download the files :) With streaming video a compressed video is usually broken into a number of chunks say about a half second long each. The actual entire video file is in one piece but each chunk can be downloade...
[ "url" ]
[ "url" ]
ctd3p9
how do whetstones sharpen knives? Why and how are they better than a regular 4$ knife sharpener??
im trying to figure out the best way to take care of my cooking equipment.
Technology
explainlikeimfive
{ "a_id": [ "exk4ph2", "exk4o1w", "exk4idt", "exkmd9r", "exk43bs" ], "text": [ "Whetstones actually file away small bits of of the metal in order to sharpen the knife in question. This gets rid of any knicks or cuts or damage to the blade edge. This means they can **keep** a blade sharp **...
[ "url" ]
[ "url" ]
ctdufm
Why can't you create your own ISP to access the internet?
Technology
explainlikeimfive
{ "a_id": [ "exk7fmq", "exk6s59", "exk6vd0", "exkyzap" ], "text": [ "So you want to become an ISP. First you need your own network that your customers can connect to. If you just want to be your own customer that's fine, this just reduces the complexity of the network to one node and all you r...
[ "url" ]
[ "url" ]
cte9v6
How do these advertisements work, when they are put on one side of the glass and you can see them from that side, but not from the other side?
I hope I described it well enough, but I'm thinking of those big advertisements on the sides of buses and fast food places and stuff, when the ad is on one side but from the inside it looks like the glass is clear and nothing is there.
Technology
explainlikeimfive
{ "a_id": [ "exk98vg" ], "text": [ "Oh I know what your talking about the factory I work at has those, interesting thing you can't see them from far away either under certain light settings. It's actually called perforated window vinyl and basically it works like this they pop a bunch of holes in it which...
[ "url" ]
[ "url" ]
ctfb5z
How the hell do I secure myself from data leaks?
I recently found out about all the leaks and stuff and that apparently my email was leaked and I just freaked out. So of course I started google the shit out of it and there's so many words and things I have no clue what they mean or what it is for so it was kind of a torture for me. I don't do shady stuff on my pc, bu...
Technology
explainlikeimfive
{ "a_id": [ "exkdxnm" ], "text": [ "Unless their plan is to rob you or post your nudes on Facebook I wouldn't worry so much about it. There isn't a hacker on earth who gives a shit about your search history. Get a VPN if you're paranoid but still relax.." ], "score": [ 6 ], "text_urls": [ ...
[ "url" ]
[ "url" ]
ctgzah
Drive partitions. Is it like splitting one drive into two smaller drives? If so, then when is this useful?
Technology
explainlikeimfive
{ "a_id": [ "exko7r8", "exko2q9" ], "text": [ "I usually use it to separate my own data from Windows. That way when I inevitably destroy windows, i can reformat just one partition without having to worry about recovering data. The main use and need is that partitions can be formatted differently. For ...
[ "url" ]
[ "url" ]
ctil9d
why are sub pixels on monitors and TVs different shapes?
I was watching a video by the slo mo guys and i was wondering why the pixels when they showed the LED and OLED TVs had different shapes. This image explains it more: [ URL_0 ]( URL_0 ) The red sub pixel is a sharp rectangle where as the green and blue sub pixels are a sort of smooth-rounded-cut-in-half square. Are they...
Technology
explainlikeimfive
{ "a_id": [ "exkzc78" ], "text": [ "That's actually a super weird arrangement. Normally green is actually smaller because the human eye is more sensitive to green light." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
ctj3vp
How does Google Maps know the exact coordinates of roads? Where does it get this data?
Technology
explainlikeimfive
{ "a_id": [ "exl2xfp" ], "text": [ "Well, the United States government publishes thousands of maps every year. There is also publicly available satellite photos which can be cross referenced with those published maps. And they also have the Google Street View vehicles, which use GPS and are attempting to ...
[ "url" ]
[ "url" ]
ctktz0
DVI-D vs VGA cables
I got a new monitor off my dad and he wants to use an adapter because my pc has no VGA ports (that work) what’s the difference between VGA and DVI-D?
Technology
explainlikeimfive
{ "a_id": [ "exlftoo" ], "text": [ "VGA is analog-only and carry only a video signal. DVI-**D** cables are digital only and carry only a video signal. DVI-**I** cables both carry a DVI video signal, AND a VGA analog signal for backwards compatability, allowing you to use passive DVI-I to VGA adapters or c...
[ "url" ]
[ "url" ]
ctnoj2
how do wireless chargers work?
Technology
explainlikeimfive
{ "a_id": [ "exm4vdx" ], "text": [ "Electrons moving through a coil create an electromagnetic field. Conversely, if you put a coil in an electromagnetic field, you can get electrons to move. The charger has a coil that creates an electromagnetic field, and your phone has a coil that picks up the electroma...
[ "url" ]
[ "url" ]
cto8iq
Why do computer screen pixels change colour when pressed on?
Technology
explainlikeimfive
{ "a_id": [ "exm9mvu" ], "text": [ "LCDs are liquid crystal displays. They rely on liquid crystal in order to attain the dimming of pixels with electricity. When you push on them, the liquid is somewhat displaced, and so the area around your finger does not get as dark as it is meant to." ], "score": ...
[ "url" ]
[ "url" ]
ctpryl
how is google satellite view so detailed in certain areas especially when it comes to 3D?
Google satellite view doesn't cover every area so in some it looks like a bad photo where 3D isn't even possible but for some more famous areas and cities, it looks literally like a mock up of the area with easily visible windows (if you pick 3D view) and other details.
Technology
explainlikeimfive
{ "a_id": [ "exms6um" ], "text": [ "Not all of Google Maps Satellite view was taken from satellites. For big cities and stuff Google will pay a company to fly overhead in a plane (or helicoptor?) and take much higher resolution pictures. Then they stitch the pictures together to make a single continuous p...
[ "url" ]
[ "url" ]
ctqu0s
How are Raster images and Vector images different?
If raster uses pixels and vector uses "math", aren't vector images also using pixels, because the screen displays in pixels?
Technology
explainlikeimfive
{ "a_id": [ "exmuv2q", "exncfp3" ], "text": [ "For a raster image like JPEG or BMP there is a fixed number of pixels and the image contains details on the value for each pixel. JPEG requires a bit more math to get to that value and BMP just straight has the pixel by pixel values, but both of them are ...
[ "url" ]
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ctt49k
Programming Functions and why are they so special
I'm still trying to wrap my ahead around this concept. I've done basic maths, so I know that f(x) = x is like a function, but I can't find an intuitive way of explaining why some functions don't have to return values. In addition, what separates functions from just lines of code?
Technology
explainlikeimfive
{ "a_id": [ "exne1dd", "exnfmyz" ], "text": [ "You use functions to break up the code into pieces. Each function should perform one task, if it’s more than that, it can be broken up into even more functions (that’s sort of what abstraction is). Some functions may need to return a value, but some may n...
[ "url" ]
[ "url" ]
ctvvc5
How youtube channels for kids make money?
Technology
explainlikeimfive
{ "a_id": [ "exo95x4", "exob1nu" ], "text": [ "Ad Revenue. Little kids are more likely to watch the same video over and over again which adds up quick. And since these channels have nothing that would anger advertisers they aren't at as high of risk of demonetization as other channels who target older...
[ "url" ]
[ "url" ]
ctwch1
The difference between computer programming, computer engineering, software engineering, computer science, electrical engineering, and IT, and any overlapping between any/all of them.
Technology
explainlikeimfive
{ "a_id": [ "exoehu1" ], "text": [ "IT is the overarching term for all that stuff. Computer programming is creating the programs that your computer uses. Computer engineering is building the hardware that your computer uses. Software engineering is studying and building new software for use in a wide vari...
[ "url" ]
[ "url" ]
ctx4qg
How do email services know which emails should be filtered as spam and which ones are not?
I was thinking about this while applying for jobs. I noticed that autogenerated emails from companies came through to my inbox but the ones from spammy fake companies offering jobs didn't.
Technology
explainlikeimfive
{ "a_id": [ "exopk4w" ], "text": [ "There are a variety of systems to handle this. Some systems look for things on the email. The subject, the body. Look for things like generated from emails, font changing, etc. Another system looks at the email process trail. How did it get delivered into the mail syste...
[ "url" ]
[ "url" ]
ctz8zj
How do they re-release full HD movies of older movies like 1985's Back to the Future, that are crystal clear?
Technology
explainlikeimfive
{ "a_id": [ "expe0x3", "expece2", "exq4lya", "expyw1n", "exqroj3", "expuq6c", "exr4aoo", "exqcxsp" ], "text": [ "Older movies were shot on film. Film doesn't have a \"resolution\" in the same sense as digitally shot movies, because it isn't stored as pixels. Film is just layers...
[ "url" ]
[ "url" ]
cu50ac
What changes when a popular from 40-60 years ago when it is "digitally remastered"?
Sometimes I notice that there are two different versions of the same song online, except one of them just says "digitally remastered in 20xx". I never hear any differences in the songs. Anyone?
Technology
explainlikeimfive
{ "a_id": [ "exs9a56" ], "text": [ "One thing they can do is remove any unwanted noise, clicks, hiss etc from the track, boost certain frequencies say to give it more bass, if they have access to the original multitracks they could mix it differently. Some info here [ URL_0 ]( URL_0 )" ], "score": [ ...
[ "url" ]
[ "url" ]
cu6rn2
How do sound-canceling earmuffs cancel out sound?
Technology
explainlikeimfive
{ "a_id": [ "exrskog" ], "text": [ "The earphones have a microphone and hears the outside sound, and plays a reversed version into your ear to “cancel out” the outside noise. Ingenius really. A bit like two waves in an ocean hitting each out and eliminating both" ], "score": [ 9 ], "text_urls"...
[ "url" ]
[ "url" ]
cu7vp6
Why do black lines appear and move around when you zoom in on a picture of a television screen?
Technology
explainlikeimfive
{ "a_id": [ "exs2veq", "exs1f5e" ], "text": [ "To put it simply : because the grid of the pixels in your TV is not aligned with the grid of pixels of your camera sensor. For it to happen you would need to have exactly the same number of pixels on both devices and have them perfectly ligned up by takin...
[ "url" ]
[ "url" ]
cudpkd
I don't understand how governments can switch off the internet-connection of entire regions.
Technology
explainlikeimfive
{ "a_id": [ "extefcn", "extd2v8", "exth9xe" ], "text": [ "We sometimes think of the Internet as invisible and all around us, but in the end it's carried by cables. All the wi-fi hubs and cell towers in a region are connected to a network of cables that eventually hook up to a small number of \"bac...
[ "url" ]
[ "url" ]
cuelas
How is an open-source software like OAuth generally more trusted/secure than non-open alternatives? Wouldn't the knowledge of the exact code make it easier to find and exploit flaws?
Technology
explainlikeimfive
{ "a_id": [ "extkubb", "extpawk", "extvheq" ], "text": [ "The \"safety\" of open source software comes less from the \"harder to exploit\" part, and more from the fact that people know exactly what's happening. When you install some software from another person, you dont really know what exactly i...
[ "url" ]
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cuelku
What instrument/equipment is disrupted by my active cellphone when flying on a modern airplane?
Technology
explainlikeimfive
{ "a_id": [ "extl1iq", "exuirm7", "extkvxq", "extwl7b", "extq9xl", "exvoxu8" ], "text": [ "None. Aircraft instrumentation may have been possibly affected by early cell phones and walkmans etc., **but now they're designed with cell frequencies and interference in mind. No, the reason wh...
[ "url" ]
[ "url" ]
cuemxf
Why do windows computers take so long to shut down?
Technology
explainlikeimfive
{ "a_id": [ "extpja6", "extm4mi" ], "text": [ "Windows will gradually shut down all of the various background programs and update the registry during the normal shutdown procedure. Because Windows tends to have a lot of junk running at any given time, sometimes it takes a while. It definitely helps to...
[ "url" ]
[ "url" ]
cug9v7
Why do MRIs take so long compared to other forms of radiation?
Technology
explainlikeimfive
{ "a_id": [ "exu513r" ], "text": [ "I'm going to assume you are asking why it takes a long time versus other medical imaging techniques. An x-ray is just a picture, so it is done very quickly. A CT scan is basically just multiple x-rays done in sequence, so it's just a bunch of pictures, which is also pre...
[ "url" ]
[ "url" ]
cuj1ui
how does web domain hosting work?
I understand that if I want a website, I need to buy the domain from someone like URL_0 but where does godaddy get the domain from? Why can’t I create one on my own?
Technology
explainlikeimfive
{ "a_id": [ "exv503t" ], "text": [ "If you create one on your own, you then have to convince everyone else in the world to listen to you and add your name to their DNS configuration. When you go through godaddy, they just hook you into the default tree that was created when the internet DNS name system wa...
[ "url" ]
[ "url" ]
cuja4k
What's the difference between URL_1 and URL_0 ?
In other words, when comparing two website pages functionally, whats the difference when the page name is before the website name vs. after the website name (with a slash)?
Technology
explainlikeimfive
{ "a_id": [ "exv2s8y", "exv3vir" ], "text": [ "The easiest way I can describe the difference would be... Say you have a department of a company. A /page would be equivalent to the department having an office within the headquarters building. A page. would be like them having a building on the headquar...
[ "url" ]
[ "url" ]
cujmwz
An infrared image.
I saw this picture captured by the hubble space telescope [image]( URL_0 ) and it said that it was an infrared image.
Technology
explainlikeimfive
{ "a_id": [ "exv6l6g" ], "text": [ "Not all kinds of light can be seen by your eyes, in fact the kinds of light we can see is a quite small part of the entire range. Light is a kind of electromagnetic radiation and the range which is visible goes between the color red (~~highest~~ lowest frequency we can ...
[ "url" ]
[ "url" ]
cujv8e
How did Steven Hawking’s speech-generating machine work? How exactly did the machine express his thoughts?
Technology
explainlikeimfive
{ "a_id": [ "exv83fq", "exvazl9", "exv7sck", "exvriiv" ], "text": [ "He had to very slowly type out what he wanted to say. It wasn’t a thought reading device, just a text-to-speech device. He didn’t have enough muscle control to speak properly himself, but even a small amount of voluntary move...
[ "url" ]
[ "url" ]
cuk68r
What is the role of an “engine” in videogame production?
Technology
explainlikeimfive
{ "a_id": [ "exvahyz", "exvaoym", "exveejy" ], "text": [ "So, imagine you're a developer. You want to make a game, but you've never made one before. Where do you start? Game engines provide a pre-built scaffolding full of functionality that work out-of-the-box. Do you want Fog in your game? Unreal...
[ "url" ]
[ "url" ]
cuk8ci
How does a missile lock warning system work?
Same as the title. Just curious how military aircraft can detect that a missle from an enemy combatants aircraft has locked onto it before it's even fired when presumably the two are using completely different systems and completely independent of one another.
Technology
explainlikeimfive
{ "a_id": [ "exvbshz", "exvc449" ], "text": [ "Radar is radio, you can detect that someone (something) is using radar because they're transmitting radio; it's much like the detectors that detect police radar speed traps. And for the second part, a missile that's tracking a target will \"ping\" that ta...
[ "url" ]
[ "url" ]
cukwp9
What are the differences, plus strengths and weaknesses of different web browsers? Explorer, Chrome, Duckduckgo, Firefox, etc.
Technology
explainlikeimfive
{ "a_id": [ "exvlo6u", "exyb8so" ], "text": [ "All those browsers are made by different companies with different visions/goals. This means some may be outdated, slow or gather all your data. Do note that I am personally using Firefox for years now, so when describing major differences I will probably ...
[ "url" ]
[ "url" ]
cum1zu
Why are virtually all file extensions only three characters long?
Technology
explainlikeimfive
{ "a_id": [ "exvqn0l", "exwt0tc" ], "text": [ "Decades ago, computer storage was really expensive, and filenames do take up some space. Microsoft created a standard that allowed the use of names that were up to eight characters long and had extensions that were up to three characters long. [They calle...
[ "url" ]
[ "url" ]
cuohw6
Why do spacecraft and satellite components need to be assembled in a sterile environment?
Technology
explainlikeimfive
{ "a_id": [ "exweugt", "exwix3x" ], "text": [ "Most satellite components are not. Spacecraft that are likely to land on other planets are clean ed thoroughly to minimize the transfer of life to other bodies. In space with no atmospheric even oils from your skin can boil and condense to ruin lenses and...
[ "url" ]
[ "url" ]
cuojbh
Why does it matter which side is up or down when microwaving bagged popcorn?
Technology
explainlikeimfive
{ "a_id": [ "exwgxjo", "exycgam", "exy0qqn", "exwnixi", "exwgsbu", "exzo0nz", "exy9ffi", "exxujt2", "exzgylt", "exzp0ub", "ey012vw" ], "text": [ "The popcorn bag has some metallic looking material built into one side of it that absorbs microwaves better. It basicall...
[ "url" ]
[ "url" ]
cus4cy
What's the difference between a SQL and a NoSQL database?
All the google results and youtube tutorials give me a full 20-40 min lecture or a tutorial on how to code on MySQL or MongoDB, but I have no clue what they're saying (I have zero background knowledge in comp sci). & #x200B; What exactly is the difference between SQL and NoSQL database? When should I use SQL over NoSQL...
Technology
explainlikeimfive
{ "a_id": [ "exyssjd" ], "text": [ "SQL Databases are designed as a series of tables that are related to each other. They usually have a fairly rigid structure. The \"S\" in SQL is for \"Structured\". NoSQL databases are usually thought of as a series of documents that have a much looser structure and rel...
[ "url" ]
[ "url" ]
cuvpxh
Is cell phone cloning a real thing? Saw it in a tv show. If it's possible, how does work?
Technology
explainlikeimfive
{ "a_id": [ "exzhndo" ], "text": [ "Cloning a phone is possible, but it will not allow you to listen in on the cloned phone. Best you’ll be able to do is sometimes get the calls meant for the cloned phone. Until the phone company detects the cloning and shuts off the whole account." ], "score": [ ...
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cuyjkt
How are mid air collisions avoided? How likely is it to occur in our days and how responsible are ground based personnel to keep flights safe?
Just watched a series where someone who was working in flight control, gave instructions to 2 flights and made them both collide, and was wondering how possible it is.
Technology
explainlikeimfive
{ "a_id": [ "ey0h6i5", "ey0fdfo" ], "text": [ "Transport airplanes have a system called TCAS. ~~Terminal~~ Traffic Collision Avoidance System. It sends out a signal that pings any planes nearby. It warns you if there's a plane nearby. If two planes get too close, it will [tell one to climb and the oth...
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cuz1br
Why do browsers such as Chrome and Edge use such a seemingly large amount of memory?
Technology
explainlikeimfive
{ "a_id": [ "ey11nxi", "ey0mxf7", "ey0zmvn", "ey11m9c" ], "text": [ "Unused RAM is wasted RAM If Chrome uses 500 MB of RAM and pages take a half second to load it's alright But if you've got 8 GB of RAM and it gobbles up 2GB precaching pages so they now only take a quarter second to load then ...
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cuzscf
that my monitor supports up to 720p however there is difference in video quality between 1080p and 720p on youtube. How is this possible?
Technology
explainlikeimfive
{ "a_id": [ "ey0xa7u", "ey0y8j2" ], "text": [ "1080p is generally higher quality and so any imperfections from compression would be hidden by starting with a better quality image overall and scaling it down. The size of a compressed frame (measured in bits or bytes as you please) is somewhat proportio...
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cv1lhm
How do radar machines time light in order to calculate distance if light is hundreds of times faster than electricity?
If light travels faster than electricity, how do radar devices switch between broadcasting and receiving and manage to accurately determine an objects distance based on the echo of a radio wave. One would think the radio echo would be long gone before the device ever had a chance fully switch over and to detect it comi...
Technology
explainlikeimfive
{ "a_id": [ "ey1a3wn", "ey1a454" ], "text": [ "Because it isn't. Electricity in a wire travels at 30 to 90 percent of the speed of light. So your premise is, fortunately, incorrect.", "Much older systems would separate the emitter and receiver, but newer versions just integrate both functions into...
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cv2udy
Why does 1080p content on a 4K screen not look bad like SD content does on a 1080p screen? Isn’t it being upscale the same way?
*upscaleD. To hell with autocorrect.
Technology
explainlikeimfive
{ "a_id": [ "ey1jyck", "ey1povl" ], "text": [ "Old content was really really low definition but that was alright because of how it was viewed To fit SD content on a 1080p screen each pixel is 2.25 pixels wide, but more importantly you're generally watching it much larger or much closer than it was mea...
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cv679o
how does the thermal vision work?
Technology
explainlikeimfive
{ "a_id": [ "ey23w4e" ], "text": [ "Heat releases energy at a certain wave length. It's the exact same kind of wave length as light, we just can't see it with the naked eye. Infra red equipment can see this wavelength and reproduced or as a colour we can see." ], "score": [ 7 ], "text_urls": [...
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cv68fz
Why is it hard to simulate human mouse movement?
I read that Websites can know that you're not a bot by looking at the mouse movement. But why would it be hard to simulate that?
Technology
explainlikeimfive
{ "a_id": [ "ey24alw", "ey2al0t", "ey26otc", "ey27b92" ], "text": [ "Because an automated system to move and click through dialogs and pages would have to be able to scan and know where the targets to click on are. No human takes a perfectly straight line between targets, and certainly not wit...
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cv7h3m
What's the difference in format if i post from a phone?
Technology
explainlikeimfive
{ "a_id": [ "ey2bdmb" ], "text": [ "It's just easier to produce easier to read formatting on a computer than it is on a phone. It's not really that hard, but it definitely seems like a lot of mobile users don't take the time to have nicer formatting." ], "score": [ 3 ], "text_urls": [ [] ...
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cv8koi
How do creators of free apps/websites make money?
Technology
explainlikeimfive
{ "a_id": [ "ey2j03w", "ey2qj7t" ], "text": [ "Most likely they are either selling ad space in their app, companies pay for the advertisement, or they collect data about you and sell it on to companies that use it for marketing. As an example, you play a game on your phone, all of a sudden you start s...
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cv8pys
how do big tech companies sell data? How do they turn users' data into profit & money?
How do they sell it and who buys it?
Technology
explainlikeimfive
{ "a_id": [ "ey2omk9", "ey2u7kl", "ey2rz7b" ], "text": [ "Most of the \"big tech companies\" you're probably thinking of (Facebook, Google) don't sell the data directly. You can't really walk up to Facebook and say \"I want to buy 3 million email addresses and phone numbers, how much will that be?...
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cv8ziu
What's the"resolution" of film photography?
Technology
explainlikeimfive
{ "a_id": [ "ey2ndcr", "ey38mte" ], "text": [ "There isn’t a specific “resolution.” It depends on two main physical characteristics of the film itself - the size of the film and the speed of the film - as well as the way that film is exposed. The first physical aspect is what format of film you’re usi...
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cvaiit
Why do older movies (not the silent movies which are intentionally sped up) look like they're fast paced when characters move across the screen?
Like Hard-Boiled by John woo for instance. The characters move quickly and recklessly across different points in the screen. The same is for other movies before 2000s. Is it cinematography or did the actors used to move really fast?
Technology
explainlikeimfive
{ "a_id": [ "ey38e9h", "ey3a1wp", "ey374c6", "ey31on5", "ey3c1jj" ], "text": [ "John Woo has a unique style featuring very fast action and editing. This doesn’t reflect the pacing of all older movies. In fact, the pacing of film sped up in the late 60s, got even faster in the 80s thanks to...
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cvava4
How does my phone identify whether or not a wall adapter allows for fast charging?
Technology
explainlikeimfive
{ "a_id": [ "ey38n1i", "ey39368" ], "text": [ "Older, passive, technology would use resistors or other means to alter resistance or voltage potential between pins of the USB connector - often the two data pins as they're not used when charging. Normally the resistance between those two pins should be ...
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cvazhx
Who Owns "Unused" Internet Addresses?
Additionally, how do these companies/websites that sell domains obtained them?
Technology
explainlikeimfive
{ "a_id": [ "ey30g6y", "ey3103o" ], "text": [ "There are two types of addresses you might be talking about: IP addresses and DNS names. ICANN basically holds all the unassigned IP addresses, and manages Top Level Domains. The IP address part is relatively simple - IANA sells IP addresses in blocks, an...
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cvc2f5
Why does it take so long to search for a file stored on a computer compared to searching Google, which can produce billions of matching results in under a second?
Technology
explainlikeimfive
{ "a_id": [ "ey384kd", "ey3c5wn", "ey3ghdp", "ey38qe9", "ey3hcvs", "ey3f2o8", "ey3vreb", "ey3uts7", "ey3jxhz", "ey3vsyv", "ey3jtf8" ], "text": [ "Google is an index. They don't just store copies of all webpages, they store an index of keywords. So if you search for ...
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cvhsky
How does Braille work?
Technology
explainlikeimfive
{ "a_id": [ "ey49ha8" ], "text": [ "Braille is separated into blocks of 6 spots, called cells, which can either be flat or indented. Different combinations represent different letters, numbers, punctuation, ligatures, or other special things like capitalization. A diagram of a portion of the braille alpha...
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cvhwvd
why can’t we have car radios that work like DVRs, so we can pause or rewind broadcasts? I hate missing the first part of something, and I’m spoiled by DVR technology. Thanks in advance.
Technology
explainlikeimfive
{ "a_id": [ "ey4h01y", "ey4bln5" ], "text": [ "My Subaru has this. When I get a phone call the radio (AM/FM/Satellite) pauses, and then resumes right where it was when I hang up. You can also rewind up to an hour.", "You totally can! There is nothing really stopping this from being available other...
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cvj3cc
How do cloud virtual machines (AWS, Azure) display your desktop?
I was recently experimenting with Azure Windows virtual machines, and noticed something strange: when you provision a virtual machine, you can configure your CPU, RAM, and SSD, but the graphics card seems to be missing. I always thought you need a graphics card to display what’s on your screen—could someone walk me thr...
Technology
explainlikeimfive
{ "a_id": [ "ey4j8xb" ], "text": [ "At the core all you need to display an image is to do some math and generate an image in memory. After that some additional hardware is needed to translate that stored info in memory into HDMI or VGA, or whatever protocol your monitor uses. With a virtual machine you do...
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cvjzip
why do video games cost so much to make?
I always hear that Triple A video games cost millions to make why is that? Is it that all cost of workers? Does it cost money for a single person to make a game? Thanks in advance
Technology
explainlikeimfive
{ "a_id": [ "ey4nzzl", "ey4nqf0", "ey4o4v7" ], "text": [ "Let's just take the basics of producing a game (and I'm sure I missed A LOT). From the top of my head: \\- Licensing an engine \\- Licensing an IP (if not working with an original one) \\- Paying the writer \\- Paying the design team, layou...
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cvk6x3
What are biggest differences between battle rifles and assault rifles?
* Also, under what circumstances is one type preferred over the other?
Technology
explainlikeimfive
{ "a_id": [ "ey4oyhu" ], "text": [ "Mostly it depends on cartridge size. Assault rifle generally means a select fire rifle that uses an intermediate cartridge. Battle rifles are similar, but use full size rifle cartridge instead of an intermediate size cartridge. Sometimes assault rifle can mean any type ...
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cvkb1d
how do 360° cameras work?
Technology
explainlikeimfive
{ "a_id": [ "ey4pfl9" ], "text": [ "Most 360° cameras have two fish-eye lenses. Each lens captures a 180° view of the area and the camera stiches the two images together to create a 360° view. Expensive cameras have more lenses so they have lesser distortion." ], "score": [ 5 ], "text_urls": [...
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cvkr8g
how cellular transmission works and why it drains the battery so much. What is the phone actually doing?
Technology
explainlikeimfive
{ "a_id": [ "ey4s97q" ], "text": [ "In order for a mobile phone to talk to a cell tower a two-way communication channel has to be set up. This involves your phone yelling out ‘listen to me’ in the hope that a tower replies. If no tower replies, your phone will shout out louder, and louder, and louder unti...
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cvlnnx
How are songs remastered?
Technology
explainlikeimfive
{ "a_id": [ "ey4x3u2" ], "text": [ "They are “mastered” using EQ and compression, which are audio engineering tools/tech. EQ is essentially volume control for separate frequencies, so you could control the volume of the low end (bass, etc) separate from the high end (treble, hi hats, etc). Compression is ...
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cvm9mb
Why do battery chargers (the type that charges AA and AAA battery's) require 2 battery's before actually charging them?
Technology
explainlikeimfive
{ "a_id": [ "ey4zt41" ], "text": [ "Because they're low quality. A high quality smart charger caters to each battery individually to give it the perfect charge, and maximize its life. The funny thing is, the highest quality charger on the market only adds about $6 to the cost of these AA Eneloop NiMH batt...
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cvn7jj
How do refrigerators work???
Technology
explainlikeimfive
{ "a_id": [ "ey55tfl" ], "text": [ "A refrigerator works by moving heat from the interior of the box to the outside. This requires a refrigerant that changes temperature when it changes density. If you have ever emptied a can of spray paint, or other substance under pressure quickly, you may have noticed ...
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cvofqx
why are car navigation and voice controls so clunky when we have the technology in phones to be very smooth?
Technology
explainlikeimfive
{ "a_id": [ "ey5dk8j", "ey5qefl" ], "text": [ "Siri and all those like it ship the audio off your phone to a server at Apple/Google/wherever to do the speech to text processing. They have huge farms of optimized servers for that. Your in-dash navigation system has to do it all itself with a relatively...
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cvq0bs
Why does train WiFi not work in tunnels if the WiFi is located on the train?
Technology
explainlikeimfive
{ "a_id": [ "ey5muic" ], "text": [ "The wifi on trains works because there is a satellite connection, in a tunnel the train and satellite cant see eachother, so therefore the wifi goes away." ], "score": [ 5 ], "text_urls": [ [] ] }
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cvq4iq
How does GPS know it's inaccuracy?
When you use google maps, it says how inaccurate it is. If they know the inaccuracy, couldn't they just use that to calculate the exact position?
Technology
explainlikeimfive
{ "a_id": [ "ey5p6i5", "ey5smo4" ], "text": [ "It's about how the GPS actually works. Your phone is \"listening\" to signals that a series of stalactites are putting out. Basically these satellites are all constantly sending signals that contain the current time. Your phone takes the signal, compares ...
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cvrm85
How can a PC benchmarking software force even the strongest hardware to its limit?
By this i mean sometimes a benchmarking app is just a looping 3D model but what about those 3D model that can make our PC overheat?
Technology
explainlikeimfive
{ "a_id": [ "ey5xg7p" ], "text": [ "Because it tells the hardware to compute something as quickly as possible. Even the strongest quarterback can throw a football only so far and even the fastest runner can only run 400 meters in so fast." ], "score": [ 5 ], "text_urls": [ [] ] }
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cvvzah
How can phones make emergency calls even when there's no signal?
Technology
explainlikeimfive
{ "a_id": [ "ey6rj1t", "ey6rj6o" ], "text": [ "The phone may display that there is no signal to a cell tower in the network for which you have service, but there may be a signal for a different network. All cell towers are required to carry emergency calls so you may still be able to call emergency se...
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cvxfu6
Difference between piano and keyboard?
Technology
explainlikeimfive
{ "a_id": [ "ey74iyj", "ey71vwc", "ey71scy" ], "text": [ "Differences include: Number of Keys — pianos have a standardized set of 88 while keyboards can differ Key Weight — piano keys have different weights by default while keyboards usually have weightless keys Sound Quality — there are some pret...
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cw1w6m
What are arrays in programming?
I have recently started learning javascript and i don't understand arrays. The way how people explain is confusing. Can anyone explain to me in a very very simple way without using words like 'entities', etc.?
Technology
explainlikeimfive
{ "a_id": [ "ey7shnz" ], "text": [ "You know what a variable is, yes? x = \"fred\". Simple. Now, imagine you have a set of 500 words, and you want to store each of them in a separate variable. Sure, you could do: x1 = \"once\" x2 = \"upon\" y = \"a\" z = \"time\" and so on, but it would be a problem. Firs...
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cw38t8
What is LinkedIn supposed to be? What is it’s purpose?
Technology
explainlikeimfive
{ "a_id": [ "ey807q8" ], "text": [ "I use it to identify key staff in a company I have interest in. Google linkedin \"the company\" and the role title you are after and quite often you'll get a name to contact. Really handy for companies with gatekeeper receptionists that won't put you through to someone ...
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cw56gh
how was electricity first discovered? And then utilised?
Technology
explainlikeimfive
{ "a_id": [ "ey8kgfj", "ey8lddc" ], "text": [ "That depends on what you mean by \"discovered\" or \"utilized\". We have records of ancient Egyptians discussing electric fish from almost 5,000 years ago. People have long known that when you rub certain substances together (amber and fur, for instance) ...
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cw6htn
What makes batteries chargeable and how are they charged in the first place
Technology
explainlikeimfive
{ "a_id": [ "ey8pg8x", "ey97qk2" ], "text": [ "There are two types of regular (AA for example) batteries. Non rechargeable batteries have two chemicals that send energy from one to another through a device. Once all the energy has moved from one end to the other or been used by the device, the battery...
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cw73q5
how do software drivers work?
Is there a brief explanation to understand how a bunch of 1's and 0's work together to install and make it function in your computer?
Technology
explainlikeimfive
{ "a_id": [ "ey8oebd", "ey8p3ou" ], "text": [ "A driver is just a string of 1s and 0s that tell your computer to be prepared for certain patterns of 1s and 0s coming from the hardware so it doesn’t get confused when it receives them", "Let's say you have a really cheap monitor that only has four p...
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cw7u6g
how do barcodes work when the same item is sent to different places with different register systems, different prices assigned, etc.?
Technology
explainlikeimfive
{ "a_id": [ "ey8tlxw", "ey8ydyb", "ey8to2d" ], "text": [ "The bar code is just another way of writing a number, which is also printed directly below the barcode. What happens is that the manufacturer says \"this bar code number corresponds to this product,\" and all of the stores list it in their ...
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cwgsuv
When listening to music on Youtube, why does audio quality vary significantly depending on where I adjust the volume? (In-website vs on computer)
To elaborate: Listening on my laptop, I've just discovered that audio quality is totally different even at the same levels of volume, depending on where I adjust the volume. * If youtube's built-in volume plugin is set fairly low (say, 25%) but my computers volume is set to 75 or 80%, then the audio quality is noticeab...
Technology
explainlikeimfive
{ "a_id": [ "eyb1g8h" ], "text": [ "This is what's called \"gain staging\". Let's pretend that you have the ability to control the volume on someone's voice via your laptop volume. If that person is talking at a normal volume, you can comfortably adjust the volume on your laptop to 50% and hear them clear...
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cwhsww
how come in movies when the cameraman is filming the actor looking in the mirror, you can't see the camera even if the camera should logically be reflected in the mirror?
This question has been plaguing me for more years than it should have.
Technology
explainlikeimfive
{ "a_id": [ "eybbive", "eybc92p" ], "text": [ "It's a little known fact, but there are a group of vampires in hollywood who are recruited a bit like stunt doubles but for cameramen when they need to film scenes about mirrors. There are also several alternate techniques that people who don't believe in...
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cwi2wc
How do Chinese keyboards work? Having literally thousands of characters in their language, how do Chinese build characters with a limited amount of keys?
Technology
explainlikeimfive
{ "a_id": [ "eybfeor", "eybg7wc", "eycl5yo" ], "text": [ "You don't type the characters, you type what the character sounds like, then a list of suggested characters pops up and you choose which character you want. See [this]( URL_0 ) for example.", "The process is called transliteration or pi...
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cwkywt
what are voxels used for in brain imaging?
Chose Technology as flair but I'm guessing neuroscience also involved.
Technology
explainlikeimfive
{ "a_id": [ "eycdsmx" ], "text": [ "Voxels are just 3D pixels. That means, one voxel is one point in a 3D image, just like a pixel is one point in a 2D image like a photo. I.e. a x,y,z (height, width, depth) coordinate mapped to another value such as color, or e.g tissue density or blood flow in brain ima...
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cwl5ip
Why are missing textures in video games portrayed as purple-black squares?
Technology
explainlikeimfive
{ "a_id": [ "eycenvf", "eycgk72" ], "text": [ "So they stand out. Developers usually show missing textures that way so when the game is being tested it's obvious if a texture is missing.", "Devs get to choose what the 'missing texture' texture looks like. They usually create a default texture file...
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cwl9qc
Before there were search engines like Google, how did we request files from the world wide web?
Technology
explainlikeimfive
{ "a_id": [ "eycgiw4", "eycfpwk", "eycg6zg" ], "text": [ "The same technology for requesting a file is still used today. Google and search engines before it just made *finding* the site you want possible. In order to visit any website you just typed out the full URL. How did you know the URL? It w...
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cwm4oh
How Two-Factor Authentication is secure when you can submit any phone number to authenticate?
I just logged into my google drive account; I already have my phone linked to my google account, and they wanted a two factor authentication, no problem, but they let me submit a phone number to authenticate with. It didn't auto choose my own. How is this secure at all?
Technology
explainlikeimfive
{ "a_id": [ "eycqab6", "eycxrew", "eycrola" ], "text": [ "Two-Factor Authentication is secure if the person setting up the 2FA is the owner of the account. Just like a password is more secure if the person who sets the password is the owner, and it's insanely insecure if it's set by someone who sh...
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cwmjsl
How do near-black colors work on OLED screens?
I've read that OLED displays work by turning off electricity for an individual pixel which is displaying pure black, eliminating the backlight and displaying the deepest black possible. My question is, as soon as you have something that's almost black, but not *pure* black (like `rgb(1,1,1)`), does the depth of the bla...
Technology
explainlikeimfive
{ "a_id": [ "eycywk2", "eycvfqj", "eycxec2" ], "text": [ "OLED pixels only produce as much light as they need. black produces no light so it uses no electricity. dark grey produces a little bit of light, so it uses a little bit of electricity OLED power use can be approximated with a simple calcul...
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cwokav
Safely eject USB key feature on desktops.
How does it work?
Technology
explainlikeimfive
{ "a_id": [ "eyddr5w", "eyde1xi" ], "text": [ "In the days of yore, USB drives were slow. So if you needed to work on a file on a usb, the file manager would do a little trick. When you hit save, it would save that file to RAM really quickly so you could get working again quickly instead of waiting 30...
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cwqmrx
Why is CCTV footage so bad in quality when other types of cameras can film very well?
Technology
explainlikeimfive
{ "a_id": [ "eydvygm", "eydvuhe" ], "text": [ "The better quality you have, the more expensive it is to purchase, the more storage space it requires, and it might be less reliable. You might not want to spend $20,000 on a setup if $5000 is enough, even if it means you get \"bad but usable\" quality in...
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cwso7j
How does data get corrupted over time?
Technology
explainlikeimfive
{ "a_id": [ "eyeliwn" ], "text": [ "Data doesn't get corrupted. However, data is stored in some media and that media can deteriorate - resulting in corruption. The causes of corruption depend on storage technology, and some technologies have very long lives (think gall ink on parchment). Flash drives stor...
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