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c33o1f | how did we manage to discover bread and other pastries? | Technology | explainlikeimfive | {
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"Bread is just mushed up grain and water left to sit for a while and then heated. Over time, the process has been refined to produce better results. Pastry follows the same path but adds refined animal fats - probably after people realized how good bread dipped in roasted meat drippings tasted."
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c343mr | when watching a live sports broadcast, why does radio tend to deliver audio feeds a few seconds before transmitted via television? Why are they not equally quick? | Technology | explainlikeimfive | {
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"URL_0 Gives the broadcaster time to delete nudity, profanity, or anything else they don't want going to air. With radio, it's just the play by play guys on the microphone. Far less likely for something unwanted to go to air, so they don't need to worry about it.",
"In the old days of analog TV, the radio and TV would be in sync. With today's digital video, there are delays inherent in the compression/decompression process. The video is usually transported in compressed format and may need to go through several compression/decompression cycles. The final delivery via broadcast is the most compressed and has the longest delay. Also, TV is more likely to be sent via geosynchronous satellite which adds another quarter second. Audio-only compression has much lower latency."
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c36nfn | What exactly is a Ddos attack, why is it dangerous, and how does it work? | Technology | explainlikeimfive | {
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"It’s like if you wanted to play a prank on your teacher so you got everyone in your class to call your teacher’s phone number at the same time so that they wouldn’t be able to use their phone for anything else for the time being. It’s dangerous because then they might miss out on some important phone calls. It works by infecting other computers (phones) with malware that makes them call the “phone number” unwillingly. That’s where the first ‘d’ comes from—distributed denial of service attack, as in the sources of the “calls” are distributed/spread out. An ordinary denial of service attack would just use one “phone”",
"Here’s an analogy: The United States has an interstate system that is designed to let cars move freely on and off the highway. As long as you have a car, a license and gas money, there is nothing stopping you from visiting any state or city that is connected to the interstate system. There are rules that dictate how fast individual cars can go and how they must drive, but there are no rules that dictate how groups of cars must function. If every driver in the state of Texas decided they wanted to drive to St. Louis for the weekend, there nothing in place to prevent that from happening. On that unfortunate weekend, the traffic in St. Louis would be so bad that the city would stop functioning. Police could try to mitigate traffic and turn people around, but no single individual could be punished for wanting to drive to St. Louis and you couldn’t sensibility pass a law afterwards to ban people from using the interstate to travel to St. Louis. People were simply using the interstate system exactly as it was designed. The fact that every Texan decided they wanted to visit St. Louis that weekend was an unintended abuse of the system. In a similar manner, the internet allows people to connect to websites. For your website to be part of the internet, it needs to accept connections from other computers connected to the internet. This works fine if you have designed your website to handle a couple thousand people a day. However, if every computer owner in the state of Texas decided to visit your website, just like St. Louis, it would receive so much traffic that it would stop functioning. You can try to mitigate the traffic coming into your site, but ultimately Texans are just using the internet exactly how it was designed and there isn’t much you can do about it on a fundamental level. The fact that every Texan wanted to visit your website that particular day was just an unintended abuse of the system. The difference in a DDoS attack however is that it is an *intended abuse* of how websites are designed to handle traffic on the internet. If a malicious individual has control of enough computers and a website isn’t prepared to handle a sudden influx of traffic, they can singlehandedly bring a website down just by instructing all the computers they control to send traffic to it."
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c3bvm4 | How do sound - cancelling headphones work? | Technology | explainlikeimfive | {
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"They have a microphone that picks up sounds external to the headphones. They then calculate the inverse waveform and play it as close to the same timeframe as they can manage. The two waveforms cancel each other out, resulting in silence. The ‘pressure’ sensation is due to the minute differences in time between the real and calculated waveforms.",
"Sound waves not only have frequency and amplitude which you are able to hear but also a phase which you can not detect in any way. The phase is expressed in angles, so between 0 and 360 degrees. If there are two sound sources with the same frequency then the sound will either add together or subtract from each other depending on the difference in phase. This effect is called interference as the two waves interfere with each other. So the noise canceling headphones will have microphones on them that listens for incoming sound and then play the same sound but 180 degrees out of phase. The ambient sound will then be canceled out so you can not hear it. This only works for headphones as the phase changes with distance to the sound source so you have to know exactly where the ear is in relation to the incoming sound and your speaker for you to be able to create a wave that have the opposite phase when both waves hit your ear."
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c3crr7 | how does a device know what to play for AR? Like those business cards that start playing when you point a camera at it... | Technology | explainlikeimfive | {
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"The card has a machine-readable address pointing to somewhere on the internet. That address contains all the information required to display whatever is supposed to be on the card, and the reading phone needs to download it through its data connection."
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c3fc9k | with slow internet, why do ads load without fail but content is stagnant? | Technology | explainlikeimfive | {
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"Because ads are stored on seperate special servers, requiring less time to load and search for the video ID. Source- a post from a few days ago where this same question was asked.",
"A website might prioritize loading the ad over loading the actual content. They might also be stored on special servers that are more suited for quickly uploading such content."
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c3jvqn | Why are apple computers used so often with graphics intensive projects, such as photo editing and animation, but are never used for gaming? | Technology | explainlikeimfive | {
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"Because of the history of apple computers and a series of very good advertising campaigns. Historically, Apple computers were cutting edge as far as graphical applications, so they gained a good reputation for graphic design and that sort of stuff. Recently, though, the designs of their consumer machines put style far beyond actual performance. Product listings are proud of the actually decent specs of the machines, but they ignore the fact that ventillation on the machines is severely underperforming. In order to manage the heat and noise, apple computers drop down the power of their components when put under any reasonably load for more than 10 seconds. For photo-editing and animation uses, Apple is still used because of the reputation of the brand, and the specific colour characteristics of the display. For gamers, though, high performance under heavy load for long periods of time is the most important, and that is not something that the consumer Apple products can provide."
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c3kgse | How can a game like Red Dead Redemption load quickly, while remastered old games like CTR needs loading screens that take a fair bit of time? | Technology | explainlikeimfive | {
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"Optimization. Newer games use newer engines while remastered still uses the old engines. ELI5 - think of liquids in pipes. New games are like water where older games are like a sludgey oil."
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c3l2fg | Volume past 50% on almost every car stereo, home stereo, TV, or computer speaker is uncomfortably loud but every cell phone's ear speaker needs to be above 50% just for me to understand the other person. 100% cell volume is only moderately loud. Why is this? | Technology | explainlikeimfive | {
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"Very simple. Sound is waves. Bigger the speaker, bigger the waves louder the sound. Phones have tiny speakers. TV’s and Cars have multiple ones and they are rather big compared to a phone"
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c3urbd | Top-level government direct exchange is often said to proceed via a 'secure line' - how is such a line secured? | Technology | explainlikeimfive | {
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"It varies of course but usually it involves something like end to end military grade encryption and only moving the call over infrastructure which is difficult for a listener to compromise, such as military communications satellites or secret fiber optics cables. There is no such thing as communication that is impossible to intercept and decode but it can be made impractically difficult.",
"A communications 'line' is 'secured', in the sense used in the movies, by introducing additional information that is only known to the parties at the ends of the line *before* the resulting signal enters the uncontrolled public communications network. Therefore, anyone in the middle who snoops at the raw signals flowing back and forth will see information that is 'obscured' by some (hopefully) unknown method, a process known more formally as [encryption]( URL_7 ). For analog voice it used to rely on a technique generally known as [scrambling]( URL_8 ), and there have been [lots of different devices]( URL_2 ) built in service of that goal over the years. A very early example was the [Scrambler Phone]( URL_3 ) which simply 'rearranged' the various frequencies that make up the sound of human speech in special pattern known only to the two parties in possession of matching scramblers. The big evolution was [SIGSALY]( URL_6 ), used during World War II and requiring installation of 40 racks containing 55 tons of equipment at each end! It introduced a very early form of digital encryption and relied on both parties possessing a '[shared secret]( URL_0 )' that was stored on a set of identical analog records. In modern times, where the 'line' between the two parties is some method of digital transport - which includes using a [modem]( URL_4 ) to convert digital information into analog signals for transport over an analog internetwork - [the core concepts are the same]( URL_5 ) but the implementation always relies on [rigorous cryptographic methods]( URL_1 ) rather than any analog signal manipulation whatsoever.",
"If I had to guess - - It's end to end encrypted - It utilizes \"dark fiber\". This is optical fiber cable that is owned or leased by a single user. In this case one of the governments",
"It’s a layered approach of telecommunication technology (equipment and programs). The message itself is encrypted. The circuits that carry the encrypted packets are connected to boxes that you (allegedly) cannot hack. And then there are intrusion alarms watching for breach into the network."
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"https://en.wikipedia.org/wiki/Modem",
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c3wjn1 | I just read the article on Bill Gates and big oil backing a CO2 sucking machine, why is this more effective than say planting a field of trees? | Technology | explainlikeimfive | {
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"Things that come to mind: 1. Doesn’t require the same space 2. Doesn’t require years and years to fully mature, and so is potentially at maximum effect earlier 3. It’s - and I cannot express this enough - PROFITABLE. How do I know for sure? Cause big oil (or any mega-corporation) typically doesn’t do anything other than follow the money, and they sure as hell wouldn’t consider investing in it if it didn’t have some form of monetary payout.",
"Science and a greater efficiency per acre. Trees really don't generate much oxygen individually at any given time and require a lot of space. Hence why algee is more efficient due to the fact they spread like wildfire, exist in otherwose unusable parts of the world (the water), and also are not being actively strip mined for resources at the same time. But machines can do it better with science"
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c3xtt3 | Why is the picture in night vision goggles green? | Technology | explainlikeimfive | {
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"When the light enters the goggles, it's converted to electricity, then boosted electrically, then the light hits a phosphor screen (like the screen part of old school CRT displays) and converted again to light. There's no way to preserve the color, so it's effectively a black and white image, but it's converted to Green because our eyes see better contrast that way.",
"Because your eyes see more shades of green then any other color (or so i have been told) so it gives better depth then black and white.",
"It's because of how our eyes work. They are more sensitive to green, so it's easier to see and green light is easier to look at for long period of time.",
"A company called Sierra Pacific Innovations Corp (a manufacturer of military imaging systems) has developed a full color night vision system that amplifies light 85,000 times. In fact, it has a 5 million-equivalent ISO rating. There's more information and some examples of just how impressive the results are [here]( URL_0 ). There *are* some lower-tech alternatives that already exist too though. A company named ColorTAC makes a device that clips onto standard monocular NVG's and spins two color filters in unison, which produces a color image - but the results are grainy. SPI's new tech (called the x27) was unveiled early this year, and is a fully functional product, but it's still the size of a small camcorder, so it'll need to undergo more development before it can be adapted for individual combat use - but the military is expected to be their primary customer when it's ready. Currently, it's become popular with those making nature documentaries due to it's rugged build.",
"Our eyes are most sensitive to green light and can see contrast better than black/white. All night vision does is take available light and artificially increases it and displays it to your eyes",
"Light falls on a photocathode that emits electrons in response to light. The electrons are attracted to a phosphor screen that has a thin conducting layer under it at a relative positive bias to the photocathode (to direct the electrons towards the phosphor). Of all of the possible phosphors, green (at 530nm wavelength) phosphors are the most efficient at converting electrons into visible light.",
"Because our eyes can see more shades of green than any other color, so it makes it easier for us to tell things apart with the little light there is",
"Its the most energy-efficient way to display objects that been illuminated by weak light source like stars and amplified by the inner battery. The human eye is most sensitive to green light wavelengths, so to design the most efficient and power-saving equipment the image has to be converted to green scale."
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c3yjhh | Why is 60 FPS the base for smoothness for PC gaming? | Technology | explainlikeimfive | {
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"Basically, you want your FPS to match the refresh rate of your monitor. Most monitors are 60hz, therefore 60 fps is the ideal for them to be in sync. However, if you get a 144hz monitor and runs a game at 60 fps it won't seem as smooth because they are not in sync. Monitors with a higher refresh rate are becoming more popular/affordable, however 60hz is still the most common for the price (although 75hz is gaining a lot of space too). & #x200B; So basically: The monitor will determine how much frames it can show per second and you want your fps to match or surpass that quantity thus creating the \"smoothness\" feel.",
"IMHO it’s because 60hz was the max refresh rate for most LCD monitors for the longest of time.",
"Strangely, because the US decided to standardize electricity on Edison’s 120v, 60Hz model. From there we get to interlaced television, then colour television (which stole some of the frequency to send the colour data). So it got there through a number of technologies which are no longer important. The bigger question is why it became an international standard when Europe standardized on 50Hz, PAL instead of NTSC, and 50FPS back in the day. But 60FPS won out."
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c3zi4m | Why do modern cinemas still use projectors? | Technology | explainlikeimfive | {
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"If they're using a blu-ray player, that entire wall would have to be a tv-type screen, making it the complete opposite of cost effective.",
"I think you're confusing different things. A blu-ray player doesn't display anything, it just reads data from a Blu-ray disc, decodes it and transmits the decoded data over an HDMI cable. You still need a device that actually displays the movie. A projector isn't limited by the size of the display. The farther away the projector is from the screen, the bigger the display (with some adjustments). If you wanted to use a TV screen, then the bigger the screen the more expensive it is - just compare a 100 inch TV to a 50 inch TV. In a cinema you'll need a 400 inch screen."
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c40c9d | What stops websites from taking your Credit Cards? | You know when you input it to checkout or they "save it" isn't it saved in a database? Whats stop them from using it. And I'm not sure how safe sites are with "secured checkout" I don't even know how that works and explaining that would be nice. | Technology | explainlikeimfive | {
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"Nothing stops them from using your card, but you can see how much money went where in your banking app. If you bought a shirt for 30$, and in the app you see that 30$ went to a shirt seller and another 50$ went for something you know you didn't buy, you can call your bank to block the card and see if you can get your money back. Also, saving sensitive data into database like passwords and card numbers is usually done by encrypting it. Web developers who made that website can probably see what's in a database, but they can't read it since it is encrypted so it's useless to them. Secure checkout can also mean that your card data is encrypted while traveling from your pc to the server, so no man-in-the-middle attacks can occur (no one can intercept and read card numbers before they reach the server). There's some more stuff going on which I'm not very familiar with nor good at explaining it, so I hope my answer covers some basics.",
"Tiny clarification on this. As posted previously, nothing stops them, so rule of thumb – don't enter your CC details unless you're trusting the site. Ideally – use virtual cards with limited balance. Technical side: unless website belongs to some huge company, it'll process your transactions and handle CC details through 3rd-party company (i.e. stripe/paypal). Main reason for this – saving CC data is highly regulated. No sane engineer/security specialist will ever save your CC details to database (unless there's malicious intent). So, for most sellers – they will not even see the card details, ever. It's even not about encryption – data simply not going to their servers. You submit form with CC data, it goes to 3rd-party. Once there, 3rd-party server calls website backend saying \"hey, there's a user payed you $N, credit card ID is #9812469, transaction ID is #980197-987012337\". Having that, seller can verify your payment, do returns/cancels, and even charge recurrent payments (subscriptions) – all that without having any idea of real CC data."
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c43t7s | How does fast(Flash?)charge work? What is limiting us to charge our phone/electronics to be fully charged in minutes? | With the recent release of Vivo flash charge which can charge 4000Mah in 13 minutes got me thinking. | Technology | explainlikeimfive | {
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"A few reasons why fast charging is difficult. 1. Heat generation in the battery . No charging process is 100% efficient, they all make heat (except flow batteries which charge by replacing the electrolyte). 2. For lithium cells, overvoltage damages cells. In order to make higher current flow, a higher voltage is needed. Lithium cells are damaged by voltage over 4.3V. Their chargers use a constant current at first which can be fast, but once the voltage reaches 4.3V they have to stay at 4.3V for the rest of the charge. The current then declines as the cell reaches full charge. This is why 0-70% is faster than 70-100%. Tldr : you can't fast charge beyond around 70%. 3. Fast charging requires more current which needs either thicker wire or higher voltage along with conversion circuitry. 120W at 4 V is 30A. That is not possible in a thin wire or small connector. Existing USB uses higher voltage to limit current. The phones have conversion circuitry but scaling that up to 120W takes space and dissipates heat."
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c4423w | It seems like we only cure pork into ham, but we don't treat any other meat the same way. Why? | Technology | explainlikeimfive | {
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"Beef jerky is basically dry cured beef. Fish is often spoken and in northern countries also salt cured or dry cured.",
"I believe pastrami or corned beef is also cured. It's beef brisket put into a brine for a week or two then.",
"There are many other cured meats. Salami, corned beef, prosciutto, and pancetta to name a few. Here’s a small list: [cured meats]( URL_0 )"
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c446w8 | Could another civilisation have founded another source of energy besides electricity or is it the only source? | Maybe a dumb question. I don’t know much about these but I googled this and could not find anything. We rely most things on electricity. If there was another civilisation who never discovered electricity, could they accomplish the same things we did with another sort of energy source on earth? Edit: thanks everyone for that you somehow made this art student understand this topic. you rock | Technology | explainlikeimfive | {
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"Electricity is not a source. It is just a way to move power around. The source is coal, nuke, wind or whatever.",
"Some amish communities have power tools that run on compressed air generated from gas powered pumps. Compressed air is just as good as electricity for tools but completely incapable of a bunch of the other things electricity does, and their concern is generally with technologies they fear would weaken community cohesion, so a way to transfer power that can run a power tool but not a TV ia great for them. Ultimately, electricty wasn't chosen at random, it was chosen because it was the best option. But there are other, worse options that do work.",
"Electricity is not a source of energy, it is a form of energy. It is the so to say the most premium form of energy we know because it can be tranformed into any other form of energy that we like. It can be easily transported but not easily stored and it's production has a lot of 'overhead', which means when we use lower forms of energy to transform them into electricity we lose a lot of the energy, that makes electricity the most expensive form as well. But it is only one form of energy that we find the most useful so far. There is chemical energy, heat energy, compressive energy, kinetic energy and many more that we use for specific purposes where they are more useful than electricity. I guess it would be imaginable that a civilization does find other forms of energy more useful that electricity. If for example a electrical conductors were exceptionally rare we might not be able to transport electricity that easily and another form, like gas, would be more viable, we did use a vaste gas distribution system before electricity was around, and it worked alright.",
"To add to the other answers, there are great examples in our every day life where we use things other than electricity to move energy from one place to another. Batteries, for example, store chemical energy for us to move from one place to another. That is a form of energy transfer. Almost all our batteries are built to release that energy as electricity, but there's no reason why they couldn't release it as heat. Hydraulic pumps use pressurised fluids to transfer energy from one place to another. They're extremely efficient over short distances. Or a car: Petrol has a lot of chemical energy stored in it. When we burn it in an engine, we convert that chemical energy into 'kinetic' energy - movement. And we use a system of gears to transfer that energy to the wheels Most of the things we do with electricity could be done with hydraulics, mechanics, steam, or other things. Electricity is convenient because we can make it flow through very small things. However, even our civilisation is starting to use other things. Light, for example, which we use in optical circuits."
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c45net | What's happening when two countries "launch cyberattacks" on one another? | Technology | explainlikeimfive | {
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"Kinda depends on the context. The cyber attacks can cover a large variety of things. For example the most notable one I've read about recently is where the [US is claiming they are implanting malware into Russian power grid.]( URL_0 ) (sorry for that link being Daily beast, I didn't want to give you the NYT link because of the pay wall) Basically what this would try to accomplish is being able to shut off the electricity to a large portion of Russia with the click of a button. So more or less the US would be able to disrupt a large portion of daily life in Russia with the click of a button and no life lost in the US, but a massive problem for Russia to deal with. There are also reports that [Russia did this to western Ukraine.]( URL_2 ) (again sorry for where the article is, but I don't like to link pay wall sites) Or there is the time that hackers locked out the [National Health Service in Brittain]( URL_1 ) by using ransomware to keep the files locked down. Basically they use the internet to engage in something that would disrupt life or damage part of what people use without sending in troops. Often times it could be considered an act of war without putting boots on the ground. The most extreme example I could think of is if a foreign country tries to gain access to nuclear missiles from another country.",
"Like war in general, both country will try to take down the opponent. But in cyberattacks, they'll try to immobilize the opponent computer network and services. In a world where technology are a huge part of human lifestyle and needs, cyberattack could interfere with activites in/related with those countries."
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"https://www.thedailybeast.com/america-putting-malware-in-russian-grid-nyt",
"https://qz.com/982682/doctors-locked-out-of-patient-records-after-16-u-k-health-facilities-hit-by-ransomware-attack/",
"https://en.m.wikipedia.org/wiki/December_2015_Ukraine_power_grid_cyberattack"
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c4d9xp | Why are DDoS attacks still effective? Why isnt there an effective countermeasure? | Technology | explainlikeimfive | {
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"text": [
"DoS was first demonstrated 20 years ago. DDoS came about because there were relatively simple guards to raise the shields against DoS. DDoS attacks while comparitively massive, can be held back, but it’s much harder and much, much more expensive. Edit: never answered the “why”. Reason is that it it difficult to quickly differentiate the small amount of good traffic from all the bad stuff.",
"imagine people deliberatly ringing your doorbell constantly, or at least every other minute. You will either answer bell (to no avail), or shut the bell off. Now your neighbour mentions to you why you are not answering the door like you used to do. You tell him that you are very sorry but really have no other choice until you sit the doorbell nightmare out."
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5,
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c4e4lm | Why VR games need way more power than other games? | I was thinking about this for weeks now because basically the googles moves could be a simple mouse move, right? | Technology | explainlikeimfive | {
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"text": [
"> the googles moves could be a simple mouse move, right? That isn't at all where the difficulty lies in computer games. Controlling the camera is dirt simple, the problem is figuring out the image to display for the camera position. Running the simulation of the game world, calculating how all the objects look from a given angle and lighting, is what takes up the bulk of the computational power. VR games are more demanding than other games because in order to provide the 3D effect the game world must be \"rendered\" (the term used for the processing steps required to produce the image) from two slightly different perspectives for each eye. The field of view for each eye is also significantly greater than that of a monitor so there are more things to process, and the frame rate is usually necessarily higher to avoid causing nausea which again increases the computation load.",
"A VR headset is rendering two different images simultaneously: Each eye gets a different screen, and a different image is needed on each to cause the 3D effect. Calculating motion in a headset and in a 3D space is a little harder than calculating it in a mouse too, although that shouldn't consume much more power.",
"First off, stereoscopic vision requires two images, and putting the screens a few inches from your eyes means you need pretty damn good resolution so that's double the graphics power required right there. That's the obvious well-known issue. Double the picture require double the power, more or less. The less obvious but if anything more important issue is that in order to let your eyes focus on a screen a few inches from them without excessive strain, there's a pair of great big lenses between your eyes and those screens. Those lenses bend light. A lot. Red light bends a different amount from blue light. To make your eyes see what they're supposed to, an entire second set of calculations is necessary for each pixel, and while this *could* be handled fairly efficiently by a dedicated hardware circuit... that would make the VR headset more expensive, so last time I looked into it (which was years ago, back when oculus had just started delivering on their Kickstarter) it was something VR engines had to handle using the graphics card. Third, if a rectangular monitor a couple of feet in front of you has some drops in its frame rate it's mildly annoying, if what seems to you like the entire world has drops in its frame rate that can result in projectile vomiting, so most VR games aim for a much higher frame rate than what regular games can get away with. Add all of this together and the graphics power requirements are *at least* quadrupled. By comparison, tracking a 6 DOF headset and pair of controllers is almost trivial. Scratch that, it *is* trivial. It's basic trigonometry which I learned to do in middle school (or high school, depending on the sensor setup). A modern CPU would barely notice the clock cycles used.",
"Simple version: when you're looking at something with your own eyes it can be really weird if something doesn't respond quickly or doesn't look right. When you're just looking at a TV a lot of things can be forgiven that would completely ruin the experience in VR. Mostly, the game has to read your body instead of just buttons on a controller, so it gets a lot more complicated. Complex version: A traditional gaming experience has a very select and limited number of inputs by the player, all of which can be discreet using buttons on the controller. These are all tied to premade animations that interact with the world in a very specific way, such as jumping or swinging a sword. Furthermore, many games can make compromises with their rendering by having a limited render distance and only rendering the objective that are directly in view. In contrast, a VR game has to receive analog inputs in terms of a players head and am movements (sometimes more depending on complexity) and IMMEDIATELY translate those properly into the world, as any lag would completely ruin the user experience. It's also more difficult to ease rendering burden because a render distance has to be really carefully balanced with immersion as well. Visual considerations are a lot more forgiving when you're looking at a screen then with your own eyes."
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c4ehzy | Why is speed of internet connection generally described in megabits/second whereas the size of a file is in megabytes/second? Is it purely for ISPs to make their offered connection seem faster than it actually is to the average internet user? | Technology | explainlikeimfive | {
"a_id": [
"erw5440",
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"text": [
"URL_0 > it is because the internet delivers those bytes of data as single bits at a time. And because those bits sometimes come out of order and from different server locations, it’s both more accurate and more intuitive to measure speed as a factor of the number of bits per second that an internet connection is capable of transmitting, not the total number of memory units, or bytes, it transmits.",
"It started in bits long ago, when not everything used 8 bits per char. There is no reason to change, it will make your product seem 8x slower than everybody else."
],
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15,
6
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[
"https://www.ncta.com/whats-new/why-do-we-use-bits-measure-internet-speed-but-bytes-measure-data"
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[]
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|
c4gw8u | Why would game companies like Xbox or others discontinue things like guitar hero and connect? | Technology | explainlikeimfive | {
"a_id": [
"erwg3ti"
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"text": [
"Because they lost popularity so it wasn't cost effective to continue supporting/making new versions of it. They're in the business to make money."
],
"score": [
6
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|
c4kpmz | how does the US post office know I’m using a real stamp and not just a fake stamp? | Technology | explainlikeimfive | {
"a_id": [
"erx2oqi",
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"text": [
"In reality, stamps are too cheal for post offices to really care. But there are measures in plase. For example, stamps are printed on a material that ismt just paper, so a low quality counterfit might get caught. Also, many stamps are printed with a substance that reacts to a sertant spectrum of light. In the end however, its not a good idea to counterfit stamps because it is a federal crime.",
"I am a mailman and from my experience most of the time when someone re-uses the stamp or doesn’t use one at all it’s caught at the end of the line by the carrier who hast to hand sort each piece into a case that has each stop listed by address. I am a rural carrier, in the city area there is a machine does the sorting so I don’t know how it works there, but when you look at thousands of letters every day it gets pretty easy to spot a phony. That being said we are paid on an evaluated system rather than by the time we actually worked and if there is no stamp and we have to stop at the house to collect postage that adds a few minutes to our day that we don’t really want to spend, since the carrier isn’t getting paid for it. A lot of the time I just let it go."
],
"score": [
12,
9
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c4oh7g | How come Apple and Samsung, AMD and Intel, Sony and Microsoft, TV manufacturers, etc, are reaching the same technology breakthroughs at roughly the same time? | Technology | explainlikeimfive | {
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"All have huge R & D budgets All use the same market research to plan their next R & D. R & D is rarely faster if you just pump more money into it. All have similarly (but subtantially) skilled engineers. So, all are basically doing the same research, with the same market data, with equally smart people, with the same top-of-the-line equipment. So all get to the breakthrough at roughly the same time.",
"Industrial espionage and patent infringement coupled with logical next steps based on current technology being achieved in parallel by different companies. Also, many so called \"breakthroughs\" are based on marketing not whether the technology is new or innovative. Many so called breakthroughs were well understood for many years and only added into production items when costs allowed profit or because a rival used that tech and now they need to keep up with the Jones.",
"These companies rarely make everything they produce by themselves, and the development of new products is more often based on the parts they can buy than what features they can add. The most obvious one is display panels. It's not uncommon for phone manufacturers (or even TV manufacturers) to buy their display panels from elsewhere. As a result, multiple manufacturers can sell pretty much the same product. In the case of AMD vs Intel, it's because they don't own big semiconducter foundries. They get their chips made by someone else. And these foundries, in turn, are driven by what equipment is available. This means they have about the same amount of silicon to work with on each processor.",
"In addition to things mentioned in the other posts, a lot of development is coming from research teams at universities that spin off into small companies. They then license their new technology or partner to the big companies.",
"amd and intel are chip companies. they have breakthroughs whenever it is possible to create smaller conductor tracks on chip dies, because there is more room than that means more complex structures and less energy. apple, samsung and sony rely on these new chips because they use mostly the same chips and the chips are at the same level of technology, they have their breaktroughs at the same time. also with gaming consoles if you take sony and ms."
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c4p6tm | What is an internet "route leak"? | Technology | explainlikeimfive | {
"a_id": [
"erxoatp",
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"text": [
"This is greatly oversimplified but... Routing on the Internet works by one operator telling its connected peers what networks they serve. So, for example, if Verizon is ABC Corporation's ISP, they tell Cogent, AT & T, Comcast and everyone else they connect to that they can route to ABC's IP addresses. The other ISPs use this information to determine where data gets sent. A route leak happens when an ISP says it can route to a network they can't, either by accident or maliciously. Sometimes customers have multiple ISPs and have to run the same routing protocols as the ISPs do for everything to work. If a customer of, say, Cogent leaks a route into Cogent that they don't actually have and the route is attractive enough, traffic will be sent there even though Cogent has no way of delivering it. A real world analogy would be putting up an \"Exit here for Disneyland\" sign along Interstate 40 in Oklahoma. Traffic from the east coast would take that exit and end up nowhere near the right place.",
"Is this what was going on with Level 3 routing this morning in the US?"
],
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c4t8wm | Why does overheating makes computer performance lower ? | Technology | explainlikeimfive | {
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"text": [
"Because the the frequency the operate at get reduced so the do not get even warmer and result in permanent damage. You can build a system that operate at full speed until it get so hot so the parts get fried and you have permanent damage and a lot of CPU:s in the past did that. The option is to slow down so less heat is generated and the survive but opterat at lower speed. So the lower performance is a protection mechanisms from physical damage from to high temperature. There exist effect that make CMOS chips slower at high temperature because resistance higher warm silicon so the max frequency you can operate at depend on the temperate. That start to get relevant of you overclock a lot and is close max possible performance but not the case for normal operation.",
"Heating up wires increases their resistance, which, essentially, slows the speed at which electrical signals can be transmitted/received.",
"Modern computers have temperature sensors built into them, and if they start getting too hot they 'throttle down' their performance to generate less heat to protect themselves. If it gets hot enough, they can even shut themselves down. Leave your phone in the sun on your car dashboard during a hot afternoon, and there's a good chance it'll refuse to turn on until it's had time to cool down."
],
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3
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|
c4utt2 | Why is it important for websites to verify that you're not a robot? | Technology | explainlikeimfive | {
"a_id": [
"eryfo92",
"erymztk"
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"text": [
"Spam bots are a common method of malicious online robot. They spam message boards or other internet sites with repeated advertisements (at best, more malicious things at worst). they also participate in phishing scams (where they try to steal your password/information). Those verification steps help cut down on those bad actors.",
"There's a few malicious things that bots can do if you allow them to use your website freely. Others have mentioned spamming advertisements or phishing scams. Another thing they help to prevent are DDoS (Distributed Denial of Service) attacks, where bots send thousands of requests to a service in order to clog it up and prevent it from taking requests from real users. Imagine if you owned an ice cream shop. A competitor across the street wants to make sure you can't sell any ice cream so they get all the customers. So they decide to hire 100 people to stand in line, wait for a few minutes to decide what they want, and then leave without buying anything. This would make it impossible for you to sell ice cream to your real customers. So your solution is to have someone stand outside and question everyone who comes in about their favourite flavour of ice cream. Only those with convincing answers will be let in and the fake customers will be turned away. Some will still pass the test, of course, but a few fake customers won't disrupt your service nearly as much as the 100 that were coming previously."
],
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10
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c4w3vz | what happens to deleted items on a computer? Where does all that data go? | Technology | explainlikeimfive | {
"a_id": [
"erym7tq"
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"text": [
"It is marked as deleted by the operating system, and is then considered free space. It will be overwritten by other data later. Which is why if you want to undelete something you need to do it quickly."
],
"score": [
3
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c4xz0l | How are Teslas and other cars with touch screen computers able to sit in the sun without overheating, but smartphones can't? | Technology | explainlikeimfive | {
"a_id": [
"erz18ag"
],
"text": [
"Nah these responses are too complex still here's the best one: Car designed like that, phone not"
],
"score": [
4
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c4z05w | How do speakers replicate sound? | Technology | explainlikeimfive | {
"a_id": [
"erz1cdg"
],
"text": [
"When you drop a stone in calm water, ripples spread from the point it entered the water, and when something makes a sound, similar waves spread through the air, you just can't see them. If you put a microphone near the sound source, these waves will vibrate the diaphragm in the microphone, which is attached to a magnetic coil, and the movement of the coil creates a very small electrical current that mimics the 'shape' of the sound wave that created it. Amplifiers do exactly what it sounds like, they take that tiny electrical 'wave' and amplify it until it's strong enough to make a coil 'vibrate' its magnetic polarity next to a huge magnet, and that makes the coil move exactly like the original sound wave did. That coil is attached to a paper cone which makes more air move and thereby reproduces the original sound. The waves can get pretty complex if the sound source is an orchestra or a rock band, but the principle still works just the same."
],
"score": [
3
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|
c4zfmy | What can a Raspberry Pi do? | Technology | explainlikeimfive | {
"a_id": [
"erz3a89"
],
"text": [
"Its a mini computer. So anything you want a cheap, small computer for. I use one for an emulator (playing old video games). I have another one I use as a wireless print server. At work, we use it in place of a computer (its displaying a dashboard on a TV, so computing power isn't needed). You could use it as a media server. There are many other uses."
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|
c54gq5 | How Does Snapchat Know I Screenshot Something? | On that note, does someone (Apple, developer, the phone company etc.) know if I take a screenshot of, say another app, like Safari/YouTube/Bing? | Technology | explainlikeimfive | {
"a_id": [
"erzrhtm",
"erzx438",
"erzuwas"
],
"text": [
"They check for the button input, so when you hit the two buttons to screenshot, Snapchat recognizes that input",
"Snapchat on Android appears to monitor for the creation of new image files and just assumes they were created by screenshotting. I was once transferring some images on to my phone by USB and browsing snapchat at the same time, and each time a file was copied over snapchat displayed the \"you took a screenshot!\" notification.",
"Apple provides developers with a method to check (they can be notified of a screenshot, and they can check if the screen is currently being recorded). Apple doesn’t track screenshotting in their own apps, and websites can’t see that information. But, yes, theoretically any app can tell if you’ve screenshotted or recorded content (but they don’t know what those screenshots/recordings contain)."
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c5gqx7 | Why does the USA have so many nuclear power plants, despite only producing 9.6% of its electricity from nuclear? | Technology | explainlikeimfive | {
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"text": [
"Your numbers are off. Us has 98 REACTORS, but only 60 PLANTS. France has 58 REACTORS in 18 PLANTS. By compairing the number of reactors in the us to the number of plants in France, you are greatly skewing the data. Let's compare apples to apples here, shall we? The US has 98 reactors for 327 million people, which France has 58 reactors for 67 million people. France has half the ractors, but 1/4 of the people. To put it another way, the US has one reactor for every 3.3 million people, while France has 1 reactor for every 1.6 million people. When you adjust for the populations size and use actual proper comparisons instead of comparing two completely different things, the US has half the nuclear reactors that France does. So no, the USA does not have very many nuclear power plants at all. EDIT. I reversed the France number. France has one reactor per .8 million, so twice the density I was saying.",
"> I literally couldn't find anything regarding why it has so many (98 to be exact) France has about 67 million people, the US has 327 million. France has a land area of 248,573 mi² while the US is 3.797 million mi². You can't just compare the number of nuclear plants directly along with the percentage of power, the countries are not equivalent.",
"I think you're kinda thinking of this almost backwards. The question should be why does the US have so **few** nuclear plants? Europe as a whole has something like 200, with places like France at one point being hugely nuclear heavy in their power generation, and Europe is in the process of decommissioning many. So why does the US get so little energy from nuclear? Europe was ablaze in it! Well, the big thing is, stemming back to the 70s... nuclear power plants are crazy expensive to build, in fact the US wanted hundreds more! But the reality of the situation was that they were so expensive and difficult to build, that it just wasn't a great option and energy could be cheaply had from other sources (such as coal, natural gas, hydroelectric, etc.) However, once you've built a plant, it can run for a very long time and do so really cheaply. There are many advocates that the US needs to reignite the nuclear industry to help better meet energy needs and get out of fossil fuels, and that modern made nuclear power plants are exceptionally safe (they are), however... the cost is still crazy, but a lot of that has to do with overzealous legacy regulation on nuclear plants. Edit: Should also point out, that France has something like 60 reactors (not the lesser number you quoted, it generally goes by amount of reactors, not by \"plants\", as many plants have more than 1 reactor)",
"The real question is why the US, and the world in general, has *so few reactors*. When you consider that reactors use a fuel source which is relatively cheap, that they produce zero carbon during operation, and they actually emit *less radiation* into the air than coal plants, it's a wonder what we don't have many more of them. Everybody worries about the possible negative effects of a disaster, but nobody bats an eye at the guaranteed negative effects of fossil fuels.",
"Where did you get the 9.6% figure? For the past few decades nuclear power has produced around 20% of America's electricity. According to [the U.S. Energy Information Administration]( URL_0 ) it is currently 19.7%.",
"You also need to take a look at the generating capacity of each of those plants. They could be rated at a higher wattage between the two nations.",
"In Canada we have a lot of hydro power. We make the electricity and put it on the grid for everyone to use. The grid also includes the US. The US makes power as well for the grid. The US can’t shut down their nuclear power during times when electricity isn’t being used ( at night, in the summer months) and sells the unused electricity to Canada at a discounted rate. Canada then sells the power back to the US during peak times at an inflated rate"
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|
c5kyr3 | how do CDs store data | Technology | explainlikeimfive | {
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"es2fcsx"
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"text": [
"Easy. A CD is etched with millions of indentations. A laser reads this, and interprets the indent as a 1 or 0 depending on refractivity."
],
"score": [
5
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c5mvhk | How do Photoshop detectors work? | Like the ones that they use over at r/Instagramreality | Technology | explainlikeimfive | {
"a_id": [
"es2rr89"
],
"text": [
"They're looking for 1) detail distortions. A genuine photo will have a quite smooth amount of detail, although it will vary with the lens - sharp where it's focused, gradually blurrier away from focus. If the image has been modified then the amount of detail doesn't change smoothly as you look across it. 2) spatial distortions, e.g. something in the background, like a pillar, that should be straight but now looks curved because of the modification of a butt in the foreground. 3) lighting distortions. Parts of the picture look like the lights shining on it are different from those on other parts of the picture - shadows in different directions, for example. 4) etc. - anything that doesn't look consistent for a real image!"
],
"score": [
14
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c5rmc1 | Why are laptop chargers so bulky? | Technology | explainlikeimfive | {
"a_id": [
"es3lhv8",
"es3mypw"
],
"text": [
"Computers use DC, power in your walls is AC. The box is a step converter so your computer can run. The shape is aesthetics.",
"The main difference between those two styles of power supplies is that the \"classic\" one has a section of the wire at high voltage, the same voltage that comes out of the wall. The box then converts it to lower voltage and the low voltage wire is the part that plugs into the laptop. You may notice that often times the high voltage wire can be disconnected from the box. This, in many cases, is to allow the use of a different high voltage wire the fits into the outlets in a different country. & #x200B; Some laptop makers use the classic style because it means selling a laptop that works with North American power and one that works in Europe is as easy as swapping which high voltage wire is included in the box. & #x200B; For makers of the \"brick\" style, they have to swap the entire power supply when selling to a different market."
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|
c5s0lf | How do steering wheels run the electrics for media/infotainment controls through the steering column when a steering wheel can turn multiple revolutions in both directions? Don't wires get twisted to the point of giving out? | Technology | explainlikeimfive | {
"a_id": [
"es3odsy",
"es3ottd"
],
"text": [
"Clock spring. It’s basically a spiral of wire in the wheel rolled up loosely so it can be wound tighter or looser depending on the direction you’re turning.",
"A device called a turn clock holds a small loop of felexible wire in a donut shape. The wire winds up in one direction and unwinds in the other. Most can go 3 1/2 turns before they brake."
],
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3
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|
c5sm9x | How does the data encryption standard (DES) from 1977 work? | Technology | explainlikeimfive | {
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"es3szfb"
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"text": [
"The message is broken into blocks of bits, which are scrambled and combined with bits from the secret key (the password, so to speak). The same secret key can be combined with the data again to undo the process. URL_0"
],
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c5sw4b | What is a Tor browser, how does it work and what makes it different to a "standard" browser such as chrome? | Technology | explainlikeimfive | {
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"A Tor browser is used for truly anonymous browsing, typically on the dark web. It conceals the user's identity by routing everything through a long series of servers in foreign countries that can't be subpoenad so that nothing ever goes directly from a server to your computer or from your computer to the server, and preventing any data from being stored locally on your machine. To keep it simple, I'll skip some of the technical aspects. Normal browsers, such as Chrome, when you type a website in, basically the target website would know this computer at this place whose owner can be tracked by a search warrant on the ISP is the one that wants this webpage, and then sends data to your computer. Your computer also sends data to the website, or stores data on your machine that says which websites you've been to. If you were doing something illegal, that's supremely easy to track. If you're not, it doesn't really matter. If you're not doing anything illegal, you very probably don't need a Tor browser for anything, although some privacy advocates maintain that the anonymity can protect your data and privacy. Source: I'm a defense attorney and I'm acquainted with how police catch people.",
"Let's use a mail analogy. Let's say you want to send an anonymous love letter to someone named Alice. You don't want Alice to know it was you who sent it, and you'd prefer not to let anyone else know you have a crush on Alice either. Using a standard browser is like handing your letter directly to Alice. Obviously not going to work. Fortunately, there are thousands of strangers who volunteer to run a love letter anonymization network. Out of the thousands of strangers, you randomly select three of them. Let's call them stranger #1, #2, #3. So here's what you do: Take your letter addressed to Alice. Place it in an envelope, addressed to stranger #3. And put that envelope into another one addressed to stranger #2, and finally another one addressed to stranger #1. Now deliver the envelope to stranger #1. Stranger #1 opens it and finds the envelope addressed to stranger #2, which he delivers accordingly. Stranger #2 opens the next envelope, finding and delivering the envelope addressed to stranger #3. Stranger #3 opens it, finding the letter addressed to Alice, and delivers it to Alice. Since it is illegal to open an envelope not addressed to you, each stranger can only open up one layer. (In Tor, this is cryptographically enforced with math, not postal law.) So what's the final result? Stranger #1 knows who sent the letter, but not its contents nor its ultimate destination. Stranger #2 knows neither who sent it, nor the contents, nor the destination. Stranger #3 knows the contents, but not who sent it. Alice also knows the contents but not who sent it. Thus anonymity is achieved: nobody other than you knows both the contents and the sender. So that's Tor in a nutshell. There's also a lot of confusion out there about the differences between Tor and VPN. In this analogy, a VPN is like handing your letter to a trusted friend who hands it to Alice. Your friend is in a position of being able to know both contents and sender, so you're putting a lot of faith in your friend (VPN) to not rat you out. But it has the advantage of not letting a stranger (stranger #3) read your letter, and it's simpler with less hops making a VPN more suitable for daily browsing.",
"Though people say it's safe, it's not impossible to trace you. Many dark web sellers have been caught before. Search \"Australian drug dealer mom\" She got caught."
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c5vpcz | How do TV channels know their viewing figures and how accurate can they be with the numbers? | Technology | explainlikeimfive | {
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"Companies use Nielsen ratings to measure audience size and composition. You used to sign up to be a ‘Neilson family’ which just meant you agree to having our viewing habits tracked. Neilson, the company, uses this sample (people that opted-in to be be tracked) to infer about the larger US population. So if most of their users are tuned into a certain program, they can infer that most of the US population in also tuning in. Today, this is much easier data to collect and more accurate. Before our TVs we’re not connected to the internet, so you had to have a Neilson box to collect data. Today most of our devices are smart devices, smart TVs, Apple TV, Fire TV, etc, so now it is like we all have Neilson boxes. Neilson has acquired companies that collect this kind of information about smart devices, so they have access to all of that viewer information. As far as how accurate, I’m not sure but they are surely directionally accurate. Meaning that if they say 90mil people are tuning in they are correct that a lot of people are watching. Neilson also knows some demographics about the area you are viewing from (your zip code for example), so they can also make a general statement about the type of people that are viewing since people tend to form communities around people similar to themselves."
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c5x7v6 | If SF can ban e-cigarettes, why can't they ban real cigarettes? | Technology | explainlikeimfive | {
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"Big tobacco has money in their pockets, so naturally you’re not going to ban someone whose “donating/gifting” you large sums of money. They can lobby for or against other products, e-cigs can help nurse people off smoking they even have fluids with zero nicotine. Money"
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c65lpc | How do those electronic scales work that calculate your body fat percentage, water weight etc as well as your weight? | Technology | explainlikeimfive | {
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"Fat, water, muscle, etc all have different levels electronic resistance. These scales send a small electronic shock (so small you can’t feel it) through the pads you stand on. This shock travels through your body and are read by the pads on the other side. Depending on how much fat/water/muscle is in your body the ending signal is changed from the original. The scale reads this change and calculates the percentages based on the change. For the weight portion, it reads that the same way as most other scales. Just pressure on the scales sensors."
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c6arj8 | why are solar-powered cars not a thing? think of the battery recharge on a sunny day sitting in rush hour! | Technology | explainlikeimfive | {
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"There is not enough energy in the sunlight to make that efficetn Sunlight is around 1000W/m\\^2 but solar panes have around 20% efficenecy so around 200W/m\\^2 in full sunlight tilted toward the sun. A Tesla model 3 is 1.9mx4.6m so it cover a area of 8.7 m\\^2 but lest say it is 10m\\^2. So you would get around 2000W= 2kW of power from the solar panels. The batteries of the model is 50,62 or 75 kWh so it would take between 25 hours and 37 hours to charge the batteries. The range of the batteries is 220 miles (354 km) for the 50kWh and 325 miles (523 km) for the 75kWh If you assume that it is at 90km/h (55mhp) you can drive for 4h or 6h but the recharge time is 25h and 37h. So in the ideal case for sunlight the solar panel would provide 4/25=0.16 that is 16% of the power you need. So you can power a regular electrical car by the sun even in max sunlight condition with tilting solar panels with the same area as the car. It practice they panes will be tilted towards the sun and you get less power. In low sunlight condition the extra mass of the solar cell will decrease the range of the car. Building solar panel that cover the whole car would be increase the cost of the car and the weight and power use for the car so it is in general not a good idea. Is is a lot more cost efficient to install fixed solar power on buildings and use them to charge a battery that you can charge the car with when you are home. There are prototype design this [like this]( URL_1 ) that provide 12km of range per hour in the sun. So you can do that but they are expensive and the the more economical option is solar panel on the house and a battery You can build [Solar\\_car]( URL_0 ) that only use the sunlight but the are not like regular cars because you need to keep the mass and the drag down. So that do not provide enough energy for a car for everyday usage.",
"We currently don't have the technology to make solar panels that are small enough, yet powerful enough, that they are useful for everyday driving. Right now, the solar panels would be heavy enough, but not provide enough energy, that they would make it harder to drive. If we get better solar panel technology, we will be able to make solar-powered cars. But for now, we can't make it happen.",
"They are a thing, it's just not really viable unless you live in southern California or a place with a similar climate.",
"Simply put, an electric car uses a lot more energy than a car-sized photo-voltaic solar panel can collect. You would need many *many* times the size of a car in solar panels to power just one electric car. You can't drive that around! Those panels would be better off staying put on top of roofs, over parking lots, or out in the desert, with the electricity brought into the car by way of power cables when you plug it in between trips. You *can* put solar panels on a car, but it will only collect about enough electricity to maybe power the A/C at best, or more realistically the radio and on-board navigation functions."
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c6e6qc | Why do some credit card machines require you to remove your card quickly then decline your card if you’re not quick enough? | Technology | explainlikeimfive | {
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"Because it is the act of moving the magnetic stripe past the reader that allows it to be read. The mag stripe is made of magnetized particles, with the orientations in different directions. The act of moving the \"tiny magnets\" past the read head induces a current in the head which allows it to be detected. The faster the movement, the higher the current. If you move it too slowly, the data can't always be read reliably and there are too many read errors for correction."
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c6e99q | What is the 'Frostbite' engine in gaming and what does it do? | I have no idea what that thing is but EA advertises it like it's the greatest thing | Technology | explainlikeimfive | {
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"Ok, so Toyota designs a car and the spend most of the time working on the internals. They make a frame, engine, and a transmission. All the internals that make a car go. One of the last things they do is the body style and interior. The cosmetics if you will. They will change the body style and interior each year but the main working parts will stay the same. That way for all the research and engineering they do they can have that car for 5-10 years, maybe more. & #x200B; Well video game companies do the same thing. They design an engine. EA has Frostbite but there are others. Unreal and Source are others. They make them solely to handle physics in game as well such as Havok. These companies put a lot of time and effort into that engine and therefore they use that engine as often as they can and license that engine to other companies. Companies than build their games using those engines. The engine contains most of the core of the game. Think of it as an engine/transmission/frame of a vehicle. So now you as a game developer can use that and build your game around that adding your cosmetics and mechanics without having to code the other things. You can modify this engine to suit your needs within reason but most of it you won't do much to. & #x200B; The really popular and well done engines tend to be bragging rights and companies want to broadcast what engine they are using. Car companies do the same thing. You know what a Hemi is right? Thats a type of engine. When you see a truck or car with a hemi badge you think certain things. EA does the same thing with Frostbite."
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c6g4us | Why do some word processors convert "I'm" to some jargon-filled thing, eg "I’m currently out of the office" | Technology | explainlikeimfive | {
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"Computers only think in 1's and 0's. We have created several different ways to translate back and forth between 1's and 0's and other characters, like A-Z and different punctuation marks, called \"encoding methods.\" For example, here is a super simple encoding method that I just made up: > A = 00000000 > > B = 00000001 > > C = 00000010 > > D = 00000011 > > E = 00000100 Some encoding methods only cover very basic characters, like A-Z and basic punctuation marks. In these simple encoding methods, there is no difference between the quotation marks at the start and the end of a word. For instance, both of these quotation marks are the same: # \"test\" But some encoding methods cover a wider array of characters, including different punctuation marks for the left and right quotation marks surrounding a word. For example, if you look closely, you'll see that these two quotation marks are different: # “test” Microsoft programs, including Microsoft word, really like to use fancy punctuation marks, including separate characters for apostrophes, left single-quotes, and right-single quotes. So when you type \"I'm\", it will automatically convert the apostrophe to a fancy one: \"I'm\" Even though these two characters look the same on most screens, they actually have different values when converted to 1's and 0's: > Simple apostrophe = 00000011011 > > Fancy left single quote = 11111100010 When you write a message inside of Microsoft Word, then save it out to a file, all those letters and punctuation marks get converted to their 1's and 0's, like you'd expect. Then, all those 1's and 0's get sent to another computer, or another program, so that they can be converted back into letters and punctuation marks for the other person to read. If the other person is using the same program with the same encoding method, then nothing will be lost in translation! However, a LOT of programs don't use the same encoding methods as Microsoft Word, which means one of two things happens: either they don't know what \"11111100010\" stands for, so they display a \"missing character\" symbol (usually an empty box), or even worse, \"11111100010\" might stand for something totally weird and crazy - or maybe even multiple characters, like the \" **’**\" you used in your example. & #x200B; **EDIT** \\- Barring Rule #4, here's an even simpler explanation: Computers have their own language, and we've invented lots of different translators to help us talk back and forth with them. When you use two different translators to translate the same message, sometimes you end up with silly errors, like the one mentioned in OP's title.",
"Computers store everything as numbers. Letters are not numbers. To fix this, we agreed upon ways to encode letters as numbers. ASCII is one of the most influential examples. Basically, ASCII splits one large number, that is the file, into smaller numbers by groups of 8 binary digits, or bits. Bits sometimes confuse people, so I'll do a switcheroo, I'll use decimal digits instead. Details relating to the numbers won't be right, but you can check actual encodings later. So let's say computers use decimals instead, and store everything as numbers like that. So instead of 8 bits, let's say our imaginary standard splits large numbers into groups of 2 digits. So if a file was 14169455, you'd read that as 14, then 16, then 64, then 55. Simple. So now we'd just check from our encoding what each of these numbers mean. Like, maybe 14 corresponds to letter 'e'? But then comes trouble. There are many encodings, mainly because there are more letters than 100 we can write with two decimal digits(256 with 8 bits). Imagine Chinese for example. So lots of places try to make encodings that supports their own characters, and usually they try to make sure latin alphabet matches ASCII so American stuff mostly shows correctly with their encoding. Which puts programs into a tough spot, because many file types do NOT specify encoding used. They just have to guess. And when they guess wrong, you get something like in title. This story has a happy ending though. In the end, lots of people went together and made an encoding to encode all the letters and symbols on Earth. It used variable length where some numbers, say, 90 - 99, mean that the next two decimals are actually part of this letter. This meant they could have more than 100 options for what a single letter can be, but for latin alphabet, the system looks like ASCII(14 is still 'e'). All praise utf-8.",
"I'm is actually fine and will never mess up. I’m will break however. If you can't see the difference that is normal. The first has an apostrophe which is ASCII and the second is a closing single quote which is not. Not every program is good about how they are encoded especially when files on disk are involved so they can sometimes be messed up. UTF-8 is a common way to encode higher things as it represents ASCII as ASCII however if you interpret it as extended ASCII with a certain page you turn the three 8 bit numbers that make up how the computer writes the character into three arbitrary characters. For extra fun use a system that incorrectly does it in a non repeatable way. A single non ASCII character can grow every save.",
"The short of it is that some programs like to get fancy when it comes to punctuation marks and other programs are stupid and don't understand all that fancy stuff and get things wrong. There are different ways for computer to store text as a series of numbers. One that used to be one that most computers used is called ASCII. It is basically a lookup table for 128 characters and their corresponding numbers. For example \"A\" is 65 etc. A quarter of those 128 possible numbers gets taken up with stuff that isn't actually a printable character, but things that were used in the days of teleprinters. This leaves 96 values for actual letters and stuff. 26 for the letters from \"A\" to \"Z\" and another 26 for \"a\" to \"z\" plus the number digits \"1\" to \"0\". This doesn't leave much room left over for other stuff like ' `´\" etc. let alone all the different non-english alphabets that use different characters like \"ö\". There were for a while numerous different expansion of that table that assigned different values for different additional characters. When converting from one of these system to another you ended up with garbage for anything but the most basic letters and numbers which are the same in most of these systems. Nowadays we have Unicode which encodes all the characters there ever were and ever will be in a single unified system. Unfortunately some older system may try to read Unicode text as being meant for a different format. Text gets converted improperly and the result is that the letters and numbers are okay but any fancy characters aren't. There is a simple \"'\" character in ASCII it has the value 39 and is called an apostrophe. It can be used for a variety of different punctuation marks from single quotes to minutes to any number of things that look like an apostrophe. There is another in one of the extension of ASCII that gets commonly used that looks like \"´\" and is called and \"acute accent\". Word and other word processors like to get fancy however they don't want to use the simple one size first all characters in basic ASCII, they want special characters for each purpose and use whatever seems the best fit. For \"I’m\" a character called \"RIGHT SINGLE QUOTATION MARK\" in the unicode docs gets used by programs like Word. The ’ may look like a ´ or ', but it isn't. When the fancy word punctuation mark gets interpreted by a dumb program that things it is ascii it sees the three bytes used to write it 0xE2 0x80 0x99 and interprets them as three different basic characters in one of the old ASCII extensions instead of the Unicode character it is meant to be. The solution is to ensure that you use the right lookup table to understand which characters the numbers are meant to be or if you can't rely on the other program displaying the message getting things right to only use simple characters that can't be misinterpreted. Trying to get fancy only to be misunderstood is not really helping anyone.",
"Because Microsoft (and some others) thought it would be really nice to silently and secretly replace the standard ' or \" characters with fancier proprietary ’ or “” curly quotations (or other characters) which only work properly in the same character set and the same font (which at the time was often only on the same OS running the same software). And/or somewhere along the way, someone opened and re-saved the document in a standard format, so those nonstandard proprietary characters got scrambled. More recently, standards have been expanded (UTF-8) to include a lot more characters, including those old proprietary characters, so as long as everyone is using the same standard, and all the software is expecting the text in that standard, things should look fine. But the software often incorrectly assumes that things are or aren't from the older standards, or it just doesn't even do the new standards right, so it tries to convert and the text gets garbled. Never use word processors (or other major office software) for any important text. Stick to standard text editors that don't make assumptions or try to fancy it up for you.",
"Because different processors may use different encoding by default. So when converting the file, if they don't speak the same language, it makes up for the character it can't read with something else.",
"Computers store and transmit data as numbers; when dealing with text, they use something called a [character encoding]( URL_0 ). Think of it like Morse Code: `Hello` would be encoded as `.... . .-.. .-.. ---`, but instead of dashes and dots they use `0`s and `1`s. This would work because both the sender and the receiver have the same understanding of how to Morse Code works (i.e. what the combination of dots and dashes mean). On the other hand, computers can use a variety of character encodings and, unless the exact same one is used when creating/saving the text and when loading/displaying the text, some things might appear different than intended. In your case, [Unicode]( URL_2 ) was used to encode `’` to `11100010 10000000 10011001` as binary, which was decoded using [CP-1252]( URL_1 ) as `’`. This happens because both of these are defaults in various systems/programs and the information related to which encoding was used is sometimes ommitted, discarded or outright ignored. The other characters have the same binary representation in both encodings, so that's why not everything gets mangled.",
"Minor niggle, btw -- that's not \"jargon\". Jargon consists of terms that are unlikely to be known or understood outside of a particular community, especially a profession; for example, unless you're a programmer or doing a related job, you probably don't know what a lambda function is, and would be confused to hear someone say \"we should probably move that to a lambda\" -- \\_that\\_ is jargon."
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c6h6ge | How does black light work? | I've always been interested in hidden messages that can only be seen when exposed to black light. So I was wondering, what makes black light seem so special? - How is it different from the light we see everyday? -How would it look like if you uses it to light up (or not) a room? -Is it related to glow in the dark objects? (I noticed that invisible ink glows when exposed to black light). -Could your eyes also hurt when looking directly at it? -How is it made? *Maybe I'm asking too much sorry* | Technology | explainlikeimfive | {
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"It isn't the \"black light\" that is special, it is the compound itself. Black light is simply a frequency of light not in the visible spectrum (the UV) for humans. Certain chemical compounds can absorb UV light (the energy in that light) and in the process re-emit light energy but this time in the visible spectrum - basically it has the property of \"changing\" the frequency of UV light that hits it. This is a property known as phosphorescence."
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c6hk0w | How does changing a dns server solve packet loss ? | Technology | explainlikeimfive | {
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"A dns server is a computer that gives your computer the numbered address for the named address you are looking for, e.g., you ask for the address of [ URL_1 ]( URL_0 ) and it replies with 2607:f8b0:400a:800::200e. If one of these dns servers has the wrong information in it, then the packets your computer tries to send out go to the wrong numbered address, and the receiving computer just throws them away. Eventually, this dns server will probably get the correct information from another dns server higher up the chain, but in the meantime, it is best to just switch to using a different one that has the correct address right now.",
"DNS is the program behind the scene that translates web site names, like “ URL_0 ” into what’s called an IP address, kind of like a phone number. Think of it like the address book in your phone. You look the name up, it calls the person by phone number. Packet loss is something else. It’s to do with the “reliability” of your internet connection. More loss is bad. Basically, lumps of data are sent over the internet and some can get lost on their way. If they do get lost, your computer will send them again but this makes things slower. If someone told you to change your DNS so you can get to a server, it’s possible that that server may have been blocked by your internet service provider - often for legal reasons. Using another DNS may get round that. Google run free DNS servers but generally it’s not something you need to change. It’s quite possible your ISP actually uses the google servers anyway.",
"It will not. Unless the packet loss issue is between you and the old DNS server. The DNS protocol is not designed to handle packet loss very well and a single lost packet can cause several extra seconds to the domain lookup process. And as modern websites tend to introduce you to dosens of new domains each this means that most websites can take tens of seconds to load even with moderate packet loss. Changing the DNS server may reduce the DNS packet loss and make the websites load much faster.",
"It shouldn't. All that DNS does, is when you type in \"[ URL_2 ]( URL_1 )\" (which means nothing to your computer, as it only understands IP addresses), a DNS server will say \"Oh yeah, I know that server, it sits at IP address [151.101.1.140]( URL_0 )\", and your computer will try to reach that address The only situation I can think of where it matters, is if you are trying to connect to some big global service with multiple servers around the world. One DNS server might return one address of that service, while another DNS server could return another, which may or may not be closer to you than the first one. Those two addresses could be along different routes on the internet, and one could have more packet loss than the other. But this is very theoretical. It shouldn't matter. DNS only resolves addresses, nothing more, nothing less, and what happens after that (like packet loss to the resolved address) is outside the purpose of DNS. Also one DNS server could be faster than another, in replying to a request. This can be perceived by you as being on a slower line (as the time between you typing in \"[ URL_2 ]( URL_1 )\" and seeing the page load increases), but again this has nothing to do with packet loss between you and the server you're trying to reach."
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c6jguk | How do websites which ask for the X, Y and Zth letter of my password avoid storing it in plain text? | Edit: This is better than I expected! I've learned things - such as the actual secure part of the process is the 'Memorable Word' that you also have to type in with the 1st, 3rd and 9th letter of your 'password'. Use anything you can remember for the password, as it will likely be stored plain-text - use a password for the memorable word, as that's actually encrypted. Also - the internet is a terrible place for poor passwords. | Technology | explainlikeimfive | {
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"There’s no guarantee that they aren’t. They very well might be. It only takes one lazy programmer or someone on an “off” day to set to store in plain text.",
"Remember the site who told you whose password you typed when you tried to create one that was already in use? Security standards of websites differ greatly. Thats why you should use different passwords everywhere, some might store it openly in plaintext, some might even be more lax about your security.",
"The whole point of encrypting passwords *(that is, seeding and hashing them and others)* is that the then produced value cannot be converted back to the password. Okay theoretically it's possible but it'd take centuries or millennia to do that. So yea, if they ask you for the 7^th letter of your password they have the 7^th letter saved in their databases."
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c6nl1d | how are we able to put information on radio waves? I know how radio waves travel, but how do we get info on them like music or news? | Technology | explainlikeimfive | {
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"There are two* ways to get information onto light (which is what radio waves are): change the brightness (amplitude modulation or AM) or change the color/frequency (frequency modulation or FM). You can't extract information from the raw carrier wave, but, if you track how the wave changes from baseline, you can extract a signal. For the simplest of analogue AM radios, you can adjust the intensity of the carrier wave in time with the sound wave. Your radio will move its speaker cone a distance proportional to the strength of the signal; if the signal gets stronger, the cone moves forwards, and if the signal gets weaker, the cone moves backwards. Since the signal strength is moving in time with the sound waves, the speaker cone will move in time with the sound - *producing sound* in the process. FM radio does the same, but equates the frequency/color of the signal to motion of the cone. Digital works the same as both, but instead of adjusting the signal based on an analog audio signal, it adjusts it to simulate the bits of data in a computer, which a more advanced radio antenna can decode and feed into a computer on the receiving end.",
"Imagine the speech from two people talking as information carried by sound waves. If they talked in front of you, you can hear them but the sound can only project so far, so fast. Now, pit those two people talking on an airplane flying at high speed. This is the radio carrier wave that helps carry information quickly and to far distances. The plane is moving too quickly for you to even comprehend what is said if you are stationary. However, if you manage to synchronize the movement of say a spy drone at exactly the same air speed as the plane, you would be able to follow and hear the conversation. Tuning your radio frequency is effectively controlling the speed of your spy drone to match the information carried by fast moving radio waves. Using set speeds of aircraft that don't overlap, you can have multiple conversations (radio stations) all on the air.",
"In the simplest terms, you can “add” waves together. This is what AM does. The music is added to the carrier wave and broadcast over the air. The receiver then subtracts the carrier wave and is left with just the waveform for the music. [Here’s an illustration]( URL_0 ). Consider the top wave the carrier wave, the second wave the music and the third wave the sum of the two. The station broadcasts the third wave. You would then tune your radio to 100Hz and your radio would subtract the 100Hz from the signal it receives.",
"The word for \"putting information on a wave\" is modulation (the wave could potentially be of any kind). A lot of people try explaining this topic using AM and FM, but analog modulation is a nightmare to explain without discussing the math. So I'll describe some digital modulation for you (digital meaning occurring in discrete steps). One of the original experiments by Heinrich Hertz featured the use of a radio wave generating circuit, and a metal ring with a gap in it which acted as an antenna. Whenever radio waves were generated, a small spark would jump across the gap in the ring. Congratulations, you can now send ones and zeros (binary) by turning radio waves on and off. This is called [On-Off Keying]( URL_3 ), and you can imagine sending something like Morse code would be pretty easy with this (tap a switch to turn the generator on and off). This is only used in things like ceiling fan remotes and garage door openers these days, because its not very robust or reliable. This is a basic form of [Amplitude Shift Keying]( URL_2 ), where the strength (amplitude) of the wave is increased in steps to show different values. You can also change the phase of a wave to encode information. I can't really explain this very well, but you can imagine it as \"jumping ahead\" or \"skipping\" part of a carrier wave (a \"carrier wave\" is just a wave of a single specific frequency). [Phase Shift Keying]( URL_1 ) involves using different \"skips\" to encode different values (image is just 2 values, or binary, though). You can actually use PSK and ASK at the same time, without them affecting each other! This is going to give you way more information carrying ability, and is called [Quadrature Amplitude Modulation]( URL_0 ) (this animation is really cool, and shows 16 point QAM). First you wait for a few bits to be ready for transmission, then you choose the amplitude and phase that represents those bits from a constellation diagram. You adjust the radio wave to that representation for a short time, so the receiver gets it properly. The reciever can then reverse the modulation to recover the bits. QAM is awesome to learn about, because its used in WiFi and Cable Internet to get crazy fast speeds (WiFi 6 uses QAM with 1024 points in the constellation diagram!).",
"In the simplest terms , imagine you want to send a signal to me You can only whistle that signal You want to send simple yes or no signals What can you do? A simple constant whistle means nothing. You can change the whistle in two ways. Louder or softer. Or higher or lower pitch. You can choose, but let me know before. Now you begin to whistle. I ask you a question. You “modulate” your whistle to answer me.",
"Imagine two kids sending each other messages using flashlights to spell out Morse code. By turning the lights on and off, “dot dash dot dash”, they’re sending messages, or “information”. Radio waves are also light, but they’re not part of what’s called the “visible spectrum”. Imagine the rainbow, and now imagine it keeps going in colors your eyes and brain aren’t set up to see. In the same way, these radio “lights” blink. An antenna picks up that signal, and translates it into audio — similar to how the bumps and grooves on an old record can “record” sound. To get a little more advanced, radio and light are both “radiation”. Light is the common name for the radiation “frequency” we can see with our eyes. Radiation can be thought of as a wave. The faster that wave crests and falls, the higher the frequency. Really high frequency radiation, like xrays, can be dangerous. Low frequency radiation, like light and radio, are generally not dangerous.",
"you're on one side of a lake, and a friend is on another. you like share messages with her using the lake. you take a stick and start creating waves at your end so she can see them at her end. how to get information across? well, you both know Morse code, and you've agreed with her before that you're going to vary the strength of the wave; the harder you hit the water, the higher the wave (amplitude), so you keep varying the strength (modulation), to send Morse code signals. so if it's high high low, that's letter A.. and so on. this works for a bit, but you can only vary the strength so much. what to do? you decide to start varying (modulating) how quickly you hit the stick (frequency), so all she has to do is count the waves at the other end. you transfer information to her by going higher or lower waves per second. those two examples basically describe AM & FM, but with water waves instead of electromagnetic waves. why waves though? a clever mathematician called Fourier figured out that every signal in the world (music, speech, etc.) is made up of neat combinations sine & cosine waves, and it's possible to use them to transfer complex data. it's really hard to explain that to a 5 year old: needs some hard math to truly appreciate.",
"u/dilsosos - Electrical Engineering student and amateur radio operator here: ELI5: there are only two kinds of radios: \"talkers\" and \"listeners\". For the \"listener\" to understand what the \"talker\" is saying, they have to speak the same language. The language they speak is the information. Engineering: for information to be transferred via a radio wave, the information has to be imposed on top of the radio wave. This is called Modulation. The type of modulation, 'modulation scheme', must be mutually compatible between transmitter and reciever. The simplest modulation that I can think of is called CW (continuous wave). This is the basis for Morse code. The modulation scheme behind morse code is now called OOK (On-off-keying), where [at the reciever] the wave is either present, or not. For example: To send the letter A in Morse code, the code is: [ .- ] [dit dah]. I would send a short character followed by a long character. You, the reciever, would hear a short character followed by a long character. What the wave is doing at this point is simply what was described above: it is present for a short amount of time, then not, then present again for a longer period of time. Up until this point, I have neglected some of the engineering aspects here. The piece of the system that doest the most work is the reciever. It takes the wave recieved by the antenna and /demodulates/ it. Demodulation is the process that reverses modulation - the information imposed onto the wave is changed back into a useable, human readable form. The reciever demodulates the [ .- ] and makes it into a [ dit dah] that you can hear. Basic recap: the radio wave itself is useless, unless you impose information on top of it. The imposition of information is called modulation, the recovery of information from the wave is called demodulation. I hope this helps, friend."
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c6qk49 | how do they monitor speed by aircraft on highways? | I did a lot of driving recently and saw this sign frequently that says something like Speed Enforced by Aircraft. How does that work? | Technology | explainlikeimfive | {
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"There are marks painted on the pavement a known distance apart. The vehicle in question is timed from when it crosses one mark until it crosses the next mark. Divide the distance between marks by the time measured and you get speed. Then they radio down the details.",
"In Virginia they do not do it anymore for budget reasons. An aircraft has not been up for this purpose in over 6 years. It's expensive to fly the plane or helicopter. Plus, if the person fights the ticket then both the police officer and pilot must appear in court. Maryland stopped their program in 2012. A few states claim to still use their helicopters and Cessnas for speed enforcement but I can't find evidence of it actually occuring.",
"There are marks on the road every 1/4mi. From a plane, they time with a stopwatch how fast it takes a car to get from one mark to the next. If speed limit is 60mph, it should take you 15 sec to go from mark to mark. Let's say they give you a buffer of 2 sec... every car that goes mark to mark in less than 13 seconds, they radio to a patrol car up ahead and identify the vehicle to pull over."
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c6se1b | How come phones (iPhones) in particular lose charge at odd rates? | Technology | explainlikeimfive | {
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"I think this a very interesting read about lithium ion batteries and how Apple is addressing this very issue in IOS 13. [ URL_0 ]( URL_0 )",
"Charge memory. It is very much not an exclusivly iPhone issue. It is a lithium-ion battery issue. Li-on is the best to date battery for the way smart phones are used, but hardly anyone takes care of the battery in a healthy way. Anyway, if you always plug in your phone to charge at 30% life remaining, eventually it just assumes its only ever going to need to deplete up to that 30% mark. So after a while it just starts to give up and die at weird levels like 30. As it ages this can increase. Bad batteries also show leaps and bounds in battery depletion as apposed to a healthy battery which would deplete in a smooth curve. Li-on batteries ideally need to be drained till the device shuts of at least once a week, plugged in to charge at no more than 15% life, and never left plugged in to a charger after it has come back to 100%. This unfortunately is very far from being convenient to most people, so the batteries shit out in 2 years, but can last longer."
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c6sgaf | Photoshop. How does it work? | Specifically, how does photoshop crop out part of the image and fill in with what was behind it? Example: I crop out my friend from the photo, and it fills in where he was as if it knew what was behind him. | Technology | explainlikeimfive | {
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"It's not actually filling in what's behind your friend; Photoshop is actually making it up using its best guess. That content-aware fill is completely fake.",
"It's using the colors and light-dark values of adjacent pixels to calculate the replacement vales for the pixels you want changed. There's more logic underneath that, but that's the idea."
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c6vmm3 | How are ratings measured? Is there some sort of signal sent to the network after I tune in to watch? | Technology | explainlikeimfive | {
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"They don't *know*, exactly. Ratings are an extrapolated statistic based on some fraction of the population who has volunteered to have their TV fitted with a device which does indeed send such a signal. If 7% of the people that have devices like that are watching something it's estimated that 7% (plus, minus, and/or multiplied by a *bunch* of statistical corrections to adjust for the age groups and viewing habits of people that decide to get a ratings box installed) of the overall population is watching, so about 20 million. Note: this is for traditional broadcast television, for online streaming each viewer does send back a signal."
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c6vq39 | What is an API? | Technology | explainlikeimfive | {
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"Application Programming Interface. You can think of it like a TV remote, you want to be able to use the TV, but you don't want to go and manually change the channel from the circuitry in the TV and you don't need to understand how the TV works to use it. An API I a way for a programmer to create a set of functions (or way to interact with some software) that doesn't require the user to understand or read the source code. From my experience it is a bit of an abstract thing, there are no rules(AFAIK) that defines what an API has to be, so it can be kinda whatever you want."
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c6vyep | Why didn’t Thomas Edison use dead bodies when inventing the X-Ray machine so his assistant didn’t have to die? | I just read an article about his assistant, Clarence Dally, and it said he was subjected to more than 1,000 times the amount of radiation we use now, for hours on end. They included a picture of his hand and it was fucked up to the max. Knowing Edison was present during a majority of it, why couldn’t he use dead bodies to eliminate others dying? | Technology | explainlikeimfive | {
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"Noone knew the effect of radiation this time. People were carrying radioactive minerals in a wooden boxes, and even much later in 50th some photo lenses were made with radium and they are still radioactive, till now.",
"They weren't really aware of what damage it could do at the time. They did note that it had seemed to have poisoned him but this was likely far too late at that point. Also, he didn't really invent the X-ray machine. He improved the mechanism. Though modern machines are based off his design.",
"I don't know much about his research, but are you sure they knew it was dangerous at the time? I seem to remember that Marie Curie has no idea about the dangers of radiation...",
"Well, let's remember that radiation was discovered the same year that Edison began his x-ray testing, so it wasn't very well understood or potentially even known to him. No one knew the dangerous side effects of x-rays at the time, and when his assistant died, Edison famously ceased working with x-rays. & #x200B; And this was over 100 years ago, when medical testing was often done on living, healthy, adult humans instead of in the lab with mice. It wasn't until 1947 that we enacted laws to protect human test subjects. Prior to this, we often would use humans for all sorts of testing, which could result in their deaths."
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c71ksd | Data centers vs servers? | Technology | explainlikeimfive | {
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"A data centre is where servers physically live. The game company would rent space for their servers in a data centre. Using different data centres allows you to have servers in different locations. Benefits being resilience to problems at a specific data centre and allowing you to put servers closer to their users. Allowing the game to pick the data centre which will provide the lowest network latency for each user."
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c724ym | Video-Game streaming, how does it work in general? | When comparing the likes of Playstation Now, Xbox Game Pass and the upcoming Google Stadia, how could "streaming video games" be summarised in a general sense? Grateful for any answers. | Technology | explainlikeimfive | {
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"Normally a computer or console will calculate the game world and generate images of it many times a second which forms the video which is viewed by the player. This is extremely demanding in terms of processing power. With streaming a game a computer far away does the calculations to form the video of the game world and that video is simply immediately sent to the player over the internet. The player then is controlling the game remotely, and the processing demand on the device the player has is much lower."
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c72jc1 | Why do Cinema screens look so clear if pixels stretch with bigger screens? | If you stretched a 4K TV to the same size as your average IMAX meaning more than 10x it's current width, wouldn't it look extremely pixelated? Is it because of the distance being much further away for a cinema viewing experience? | Technology | explainlikeimfive | {
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"How pixellated a screen looks is based on how big each pixel looks to you. If each pixel takes up one millionth of your full field of vision, then it doesn't matter how big that pixel actually is. If you took an old and really low pixel count screen, and set it a hundred feet away, it would look just as pixellated as a really nice 4k screen ten feet away. The size of a pixel scales with your distance. If you're twice as far away, the pixel is one half the size.",
"If the projector is digital, then it's using a resolution that is set based on the distance between the projector and the screen so that the image is clear. If it's a film projector, film doesn't have a resolution, so it shouldn't look blurry anyway."
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c72x08 | why do some electronic screens look wavy when they’re being taken on a phone/digital camera? | Also when I turned the picture sideways, the waves looked different. Why? | Technology | explainlikeimfive | {
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"because most electronic screens have a refresh rate. the led's or lcd's or whatever are not continuously outputting the image. they are being refreshed 60 times a second in most cases. and your camera can pick up on that. if you change the shutter speed on your camera, you can make the effect more pronounced or make it go away. but most cheap/cell phone cameras shoot at a slower shutter speed where the effects are more apparent."
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c73b55 | How does a paper ballot protect the integrity of an election? | This has been coming up a lot lately as I’ve heard a few candidates talk about using certain protocols to make sure our votes are accurately counted and not manipulated. One of the first things I always hear mentioned is having a paper receipt that shows who you voted for and allows you to see that yes, I voted for candidate X and candidate X is on the ballot. What I don’t understand is, if the concern in this case is a hacked computer system or a broken computer algorithm, couldn’t the problem accidentally or intentionally be made to occur in a way so that your paper ballot says “you voted for Candidate X” but actually quietly records that you voted for Candidate Y? How would a paper ballot be protected from this? (I’m labeling this Technology because I assume it’s a tech issue but please let me know if I’m wrong.) | Technology | explainlikeimfive | {
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"The receipt you get is a mechanical duplicate of a paper record kept inside the machine. After the election, an audit can check that the machine's totals match what's on the paper. A recount could process all the rolls of paper, if the need arrises.",
"It's much harder to burn boxes of paper ballots than to change a digital database entry. Especially if you're doing it from a foreign country. As long as the physical paper still exists, there's a real record of the voters' intentions."
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c74tpl | How are companies able to manufacture each pixel on a screen, given how tiny they are and make them work the way they want?? | Technology | explainlikeimfive | {
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"They don't manufacture each pixel individually and then combine them to make a screen. They essentially \"print\" the pixels directly onto the screen in a process called [photolithography]( URL_0 ), which is the same process that is used to make CPUs. In a nutshell, it involves applying a layer of a UV-sensitive coating onto the base material that makes up screen (or the CPU in the case of making a processor). An image of the electronics that make up the pixels is projected onto the coating with UV light, which causes the coating to harden in the places where the light hits is. The non-hardened coating is washed off, and then other chemicals are used to etch the base material where it's *not* protected by the hardened, UV-sensitve coating. Then the UV-sensitive coating is dissolved with a different chemical, and you're left with millions of microscopic, etched electronic components. That process is then repeated on the material to create all the needed layers of electronics.",
"Imagine that you are screen-printing a shirt. You could place each spot of ink manually, but that would be a massive pain, so instead you make a negitive image of the print, and use that to apply the ink. You can do the same thing with electronics. If you use negitive images of where you want each material, and apply some chemical magic, you can make a decent sized panel of LEDs, and those LEDs become your pixels. Typically they can't make a whole 50+ inch screen at once, so they would make smaller panels, and link them together on a stronger backing material. Similar process was used for LCD TVs, but the thing they printed was the conductors that move the liquid crystals. And the phosper that makes the colors for a CRT TV would have had a similar process. TLDR: make an image of what the parts should look like, then apply magic."
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c75jdi | How do fiber optics work? | Technology | explainlikeimfive | {
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"text": [
"An optical fibre is...somewhat simplified, a very, very long strain of glass. A type of glass with some chemicals mixed in, so that it's somewhat bendable. The idea is that when you shine in one end of the cable with a light, it'll come out in the other end. If you use, say, a flashlight to flash morse code, it'll be possible to see the morse code in the other end of the cable. A flashlight is pretty slow to go on and off, so you can't send signals very fast. And that's why we use lasers instead. Because lasers are very, very fast at turning on and off. And that is pretty much what a fibre cable is. A very long strain of glass, with a laser beam light in one end. And a sensor in the other end, that detects if the laser is on or off. But, it get's better. You know how different colour light has different *wavelengths*? Just like you can, in theory, shine into the fibre with a red and a green light at the same time and be able to listen to two transmissions at the same time, you can also change the \"colour\" of the laser transmitter. The result is that you actually use several lasers that transmit at the same time. Often in both directions at the same time."
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c76935 | Why do WIfi devices have an easy time spotting the existence of weak network connections, yet have trouble connecting to them? | Technology | explainlikeimfive | {
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"text": [
"Well, because they're weak. It's like when someone is talking to you really softly. You can hear that they're trying to say something to you, but you can't make out what it is. The device can see that there's a network there, but it's too weak to move data back and forth.",
"Imagine a guy shouting into a megaphone, and you are a fair distance away. You can just barely make out what the guy is saying. Now try shouting back to the guy. Do you think he'll be able to understand what you're shouting back? Probably not - if you can just barely hear him with his megaphone, it's not likely he'll be able to hear your meek no-megaphone voice. A wireless access point is like the guy with the megaphone. They have beefy antennas that can \"shout\" very loudly because it is easy to put whatever kind of antenna you want into a device that just sits on a shelf, plugged into a wall. Your phone/laptop is like the megaphone-less guy trying to shout back. In a phone/laptop there is limited physical space for wifi antennas, and power consumption needs to be low to preserve battery life. So the wireless network shows up because it can \"hear\" the access point, but it can't connect because it can't \"shout back\" loudly enough for the access point to hear. There are several ways to mitigate this effect. One method is to simply turn down the broadcast power of the access point. That's like taking the megaphone away from the megaphone guy. This ensures that a wireless network will show up in your network list only if it is likely that you'll be able to connect, but it doesn't actually let you connect from longer distances. The other option is to put antennas with better receive sensitivity into the access point. That's like giving the megaphone-guy hearing aids. With this option the access point can both shout loudly, and hear quiet responses back. This method results in an increase in the usable range of the wireless network."
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c76nbg | What do the specs on/of a computer mean? | I always see people who know a lot about PCs compare specs, which usually consists of a bunch of names, numbers, and letters. I've even told people my specs. But I have no clue what they even mean. What are these names referring to/what are they even used for? I'm not someone who knows a lot about PCs, but I haven't been able to find an answer to this that I can understand. | Technology | explainlikeimfive | {
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"The big three specs on a computer are the CPU(the brain), the graphics card (what renders games and stuff), and how much ram you have (it is super high speed memory which can significantly impact how smoothly the computer runs). Other things might be what storage is in the computer or peripherals (like monitors, mice, keyboards or gaming keypads) Most of the \"numbers and letters\" are referring to specific products/brands/items. For example the GTX 1080 Ti is a graphics card designed by Nvidia but a number of other companies (like EVGA and Asus) have made their own versions so you might see their names in the title as well."
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c775o1 | How does a computer knows the length of a second? | I mean, there must be something that lasts 1 second and serves as the base measure for the system. But what? | Technology | explainlikeimfive | {
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"text": [
"There is clock signals in the computer with know frequency that you be used to determine progress of time by the circuits. The are based on technology like a [crystal\\_oscillator]( URL_0 ) often called quartz crystal that vibrate at fixed frequency because of there physical shape. It works a lot like a tuning fork or strings in instruments that is tuned.",
"When you pass an electric current through something like quartz it oscillates as in it vibrates back and forth at a frequency which you can work out by doing some math or getting a chunk of it and passing a current through it. This vibration is a constant vibration, for arguments sake say 25000 times a second or 25 kilo hertz now computers are very good at counting so a computer can count these vibrations and will have been told him w many of these vibrations is a second. Its called a crystal oscillator and there are different frequencies of crystal oscillator but they all function the same and can be found in pretty much anything electronic from wristwatches to computers."
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c777az | Tablet screens vs E-Reader screens | I know phones and tablets are lcd screens but what are screens for e-readers (kindle, etc) called? How can they not be lit up like a phone’s screen, still respond to touch, and be able to be seen very easily in sunlight where as a phone or tablet can be on the brightest setting and still be nothing but reflection? | Technology | explainlikeimfive | {
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"[E-ink]( URL_0 ). Instead of lighting up phosphor dots like a computer monitor, it's filled with dark, electrically charged capsules and they can use electricity to bring them to the surface. It's actually a lot like a very advanced Etch-a-Sketch (except electric instead of magnetic)."
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c77rg6 | How does usb to 3.5mm work? | Yup.. Like the title says! I don't get it, why is there no DAC involved? Edit: SOLVED.. I think | Technology | explainlikeimfive | {
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"There are two ways of building a USB to headphone adapter. One is the correct way that is compliant with the USB standards, and that is to include a DAC in the adapter itself. USB is digital only, so it's against the rules of the standard to send analog audio a USB port, so the only place for the DAC is within the adapter itself. But no one wants to buy expensive headphone adapters, and an adapter with a DAC would be quite expensive. It's against the standard, but why not just use the DAC on the phone and send analog audio through USB? There's no reason why you can't do that. USB has many pins. You only need a few of them to communicate with the phone to tell it that this is an audio adapter, so phone makers did just that. You plug in one of these cheap USB C to 3.5mm adapters, and the phone sends analog audio through a few of the pins, and you don't need a DAC in your adapter. The problem with this is that because it's not standards compliant, each phone manufacturer picked which pins to use independently. They didn't agree. So there are significant compatibility issues with USB C headphones and adapters. Some adapters won't work with some phones, some headphones won't work with some phones. But the standards compliant adapters that include a DAC do not have these issues. It's kind of a mess. And that's why.",
"Not an expert, but you usually only need a few cables to make certain functions work. Like, you couldn’t plug your phone into the usb to charge from an aux port, but you could totally use it to play music using the couple of connections on a usb that do that. Also, software and firmware are usually used toallow computers to figure out where information is coming from and what the info is."
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c79n32 | Why do some phone batteries 'die' before reaching 0%? | Technology | explainlikeimfive | {
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"Cell phone batteries as they get older often have issues with judging 0% to 100%. This in most cases leads to the phone shutting down below 10% as the phone is displaying incorrect battery storage info.",
"While it will vary by battery and with age, as a battery drains it won't be able to deliver the current (amps) it could otherwise at higher charges or if it was newer. If you try to force too much current out of a battery the voltage drops (this is part of the internal resistance someone else mentioned) and that can cause the phone to spontaneously power off since its incoming power is no longer within its voltage tolerance. If you have an old device that suddenly shuts itself off when put under load (eg: playing games) this may be why, and it's a big part of why Apple implemented that feature that slows down your phone with age. Also Lithium Ion batteries if over-drained will permanently die. So there is an incentive to shut them down a little bit early to keep them outside of that danger zone.",
"Because the phone doesn't really know exactly how much charge the battery has. It makes an estimation. When it tells you that your battery has 35% charge left, that's the result of a calculation that may or not be accurate. When a battery gets old, the estimation may become wrong. The battery also becomes less ably to deliver the power it was able to when it was new, so it's possible for the phone to ask for more than the battery can give. If that happens, the phone will shut down.",
"Voltage and Charge are different things. The voltage of the battery goes down when it discharges. If the voltage is to low the device needs to power off to prevent the battery from taking permanent damage. Aged batteries have a higher internal resistance that make the voltage drop further when under heavy load, causing the „emergency“ shutdown to kick in when there is still charge left. Apple put in a mechanism that reduces peak discharge for old batteries, making them not die suddenly. It does it by reducing the CPU speed, when the battery is low."
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c7bfir | The paradox of Asimov's laws. | AI is programed with asimov's 3 laws. AI is then asked to kill subject A in order to prevent the death of subject B. It can either kill subject A or do nothing. Either choice violates the first law. Am I missing something? | Technology | explainlikeimfive | {
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"Firstly Asimov's laws are [not to be taken seriously]( URL_2 ). AI is a developing field and there's certainly a whole lot more to learn but it's pretty clear at this point that Asimov didn't stumble across actual rules that would work, at least with the way things are going at the moment. You don't code AI using English sentences and coding \"don't harm humans\" is currently not possible. That being said, the problem is very real. What you're describing is essentially the [Trolley Problem]( URL_0 ) - if an AI has to make a choice that results in death either way how should it make the choice? Self driving cars have this exact problem. If a self driving car is going to crash and can either swerve left and hit stranger A or swerve right and hit stranger B then how does it make the choice? The truth is we don't really know how humans would even make that choice in the split second they have. We have no real answer at the moment to how an AI system should respond, but people are working on it. [You can help contribute with your own judgement too.]( URL_1 ) So no, you're not really missing anything. There are scenarios where an AI may be in this paradoxical situation and people are working on the problem. It's as much as a problem of ethics and morals as it is one of AI.",
"In this case, the robot would probably break down as its internal logic fails. e.g. the Asimov short story \"Liar!\", where whatever choice the robot makes, it will hurt a human. It screams and pleads, then 'goes insane' and breaks down. Note though that some robots in Asimov's world do seem to have the capacity to judge whether harming a single human could save many other humans (e.g. 'The Evitable Conflict'). So perhaps a robot could make a judgement call as to which human could be harmed as a \"least worst\" option.",
"Asimov's laws are far from perfect. Many of Asimov's stories are about how robots attempt to balance and deal with the laws when there's conflict between them. In some cases, the robot simply malfunctions because its internal logic breaks down.",
"Asimov wrote a story called \"Liar!\" which deals with this kind of \"damed if you do, damned if you don't\" scenario. As soon as the robot realizes that he's breaking the laws either way, he screams and his program crashes."
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c7bzur | Why aren't browsers able to block all pop-ups (some of them seems to "escape the filter")? | Technology | explainlikeimfive | {
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"There's a constant battle between browser developers and popup makers. Browser devs try to get rid of unwanted popups, while the popup makers are looking for ways to trick the browser into allowing a popup. Sometimes, the popup makers find something that the browser devs missed.",
"What MROctantis said, plus the fact that advertisers are, well, kinda dinkish. I remember the early days of web browsing, when the ads would just be there, as banner items at the top, bottom and sides. Sure, they made a web page smaller, but the ads just sat there. Which was fine and dandy. & #x200B; Then they started flashing and making noise ..."
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c7cyza | Why are OLED displays capped at 60Hz (according to Dave Lee)? | Dave Lee says in his recent video that OLED panels are capped at 60Hz ([ URL_0 ]( URL_0 )). However, the Oneplus 7 pro which has an AMOLED display runs at 90Hz. So what is true or do I miss something? | Technology | explainlikeimfive | {
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"text": [
"It has to do with the panel itself. OLED and AMOLED are completely different, and AMOLED offers a much faster refresh rate than a OLED panel. That's why OnePlus is able to achieve it due to AMOLED."
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c7dnf9 | How do pixels know when and what color to display? | Technology | explainlikeimfive | {
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"text": [
"They don't. The computer sets the pixel to whatever color is needs. I'm not quite sure why you think a pixel needs to \"know\" anything. Could you perhaps explain how you arrived at that idea? I should be able to better explain what's going on then."
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c7f4q8 | how are adblockers not undetectable? | why is it so difficult to program an adblockers that is undetectable by the website? The adblocker could do all the stuff the browser would do anyway (download as file, run script, move elements around) and then in the end just not show the ad image on the screen. it could be completely "transparent" to any JavaScript, server traffic or other interfaces. even the websites selling the ad space could not complain as there is no way the block could be detected (and would just pay them like a shown ad). So what is limiting the adblocker do do it's job on some sites ? | Technology | explainlikeimfive | {
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"Yes, all of that is possible. Some of it is tricky, though, some not very wanted by end users. For instance, one of the \"selling points\" of ad blockers is that they improve performance by decreasing bandwidth and memory usage. This won't happen if it still downloads images, and runs scripts. Downloading images and running scripts means compromising the user's privacy -- you're sending valuable data to the advertiser even if you don't actually see the ad. Another thing is that by removing ads the page becomes cleaner. To really maintain the illusion the adblocker would either need to keep the layout the same (otherwise blocking is detectable by checking element positions), or maintain a parallel simulation (which takes work and resources). Transparent ad blocking would also mean real war with ad companies. It would break their statistics and make it impossible to tell if anybody is seeing anything or not, which would pose an existential crisis to them. This would possibly mean legal trouble as ad companies would do all they can to survive."
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c7gpme | Why don’t law enforcement officers use tranquilizer guns to subdue perpetrators? | Stun guns require close contact with potentially dangerous individuals, and tasers require both of their prongs to make contact to actually work. Why are tranquilizer guns (like those used to sedate animals) not used on people? | Technology | explainlikeimfive | {
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"Cop here: There's several reasons. For one, tranquilizers require time to work. In an active use-of-force situation, you're dealing with seconds at the very most. You need instantaneous options. Another is that tranquilizers require specialized doses based on size and weight. It's fine to estimate for an animal, because ultimately if you accidentally kill it, it's not that big of a deal, legally. That's not the same for a person.",
"Because they don't work fast enough. When someone is charging you with a knife, you can't wait 20 seconds for drugs to take effect.",
"You know in the movies where someone gets shot by a dart or injected with a syringe then pass out in 3 seconds, yea that is not real life. & #x200B; Usually even in animals you shoot an animal and it takes 5-10 minutes before it passes out and falls asleep. Also its pretty dangerous to do , if the dose is too low the animal doesn't pass out or is sedated enough were it can still move but ends up injuring itself or its too strong and it dies. Also it would be hard to dose it on the fly and it could also interact with any drugs the person is on. & #x200B; Example if the person is drunk , it may be dangerous to give them another sedative",
"Knocking people out chemically without killing them is [difficult. ]( URL_0 ) Weight, age, preexisting conditions etc make it extremely dangerous to try a one size fits all approach. There is a reason anaesthetist is a profession..."
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c7ixqz | How a speaker is able to make two sounds at the same | Technology | explainlikeimfive | {
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"text": [
"When a speaker vibrates, it doesn't have to move in a single pattern. It can push out, pull back all the way, push forward a tiny bit, push back a little, push forward more, and so forth. When you consider the two frequencies of sound you mentioned, when they get added together- whether they were both played in front of you and you hear them together \"live\", or they were recorded separately and mixed with audio equipment, they produce one single \"wave\", but that wave is very complicated, containing the information of both signals. The speaker reproduces the same (or very similar, given that reproduction can never be identical) wave that you'd hear if you were physically present when the two tones were produced. It's your *brain* that does the work. It takes the complex waveform and essentially breaks apart the separate sounds that have been mashed together. What you \"hear\" isn't really what you *hear*, if that makes sense- your brain is doing a lot of work to let you hear multiple sounds."
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c7ksht | How come you sometimes see red-eye in cameras with flash on, but you cannot see red-eye when you look into a mirror with lights on, even shining directly into the eye? | Technology | explainlikeimfive | {
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"text": [
"Angle. When you get redeye in a photograph generally the person is looking directly at the flash and their pupil is dilated because it’s dark (hence the flash). When you’re in a lit room your pupil is smaller and you’re looking at the reflection of your eye, not directly at the light source. (Or you’re looking at the light source but then can’t see your eye) but mostly it’s the pupil dilation and angle."
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c7l5sm | How does bluetooth work? | Technology | explainlikeimfive | {
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"text": [
"It's very high frequency (2.4 gHz) radio waves that allow two devices to not only connect to each other but also to share data between one another. It's similar to other such protocols, like wi-fi - the router and your laptop communicate and share radio waves to transmit and receive data."
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c7l5sr | De-icing planes | I’m curious here and I just can’t understand the concept. How do planes wings stay de-iced? When you are traveling in the winter I know they spray de-icer on the wings sometimes. But, when you get moving to 5-600MPH how does the de-icer keep working? In the summers, they don’t spray but last week I was flying through a snow storm at 36k feet and I know they didn’t spray before the flight. How do the wings stay free of ice? | Technology | explainlikeimfive | {
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"text": [
"SOURCE: am airline pilot It’s two different systems for different things. De-Ice Spray on the ground, and Anti-Ice equipment for in flight. The spray does nothing to prevent ice build-up during flight. The spray comes in two types: the first is just hot water (or hot water with alcohol mixed in to lower it’s freeze point so it doesn’t just refreeze as new ice). To remove any accumulated ice on the parts of the aircraft that produce lift. This is because the ice changes the shape of the airfoil and makes your wings less efficient, so with Ice build-up... you might not make it off the ground before the end of the runway. Then there is the second type. Sometimes, if there is just ice buildup on the plane, but it is not actively snowing or raining... a pilot just takes the first type and off you go! But if there is active precipitation falling, we get sprayed a second time with this next material. This second spraying is a thick, gloopy, slippery slime that sticks to the aircraft. Depending on the manufacturer, it is rated for different absorption rates... and it is designed to absorb rain/snow as it falls and keep it from freezing and adhering to the plane. The , as you start to go fast and roll down the runway, it will slough off. Different manufacturers products have different time limits they can be in different levels of precipitation before they are considered fully-soaked and time out, and your plane has to be re-sprayed to reset the timer. Basically, the whole De-Ice system is just to keep ice from building up on the aircraft while it’s on the ground. None of this spray does anything while flying, and it’s designed to all fall off the plane very shortly after take-off anyway. Then, when airborne... we have Anti-Ice systems. These are usually electrically heated or pneumatically heated (with hot air from the jet engine) metal surfaces on the leading edges of the wings, control surfaces, sensor probes, and windscreen. They operate by just getting hot and melting the ice a little so the wind can knock it off. Not all aircraft have Anti-Ice systems, as they are very expensive. Most commercial aviation aircraft around the world do, but most smaller general aviation and private planes do not.",
"In my last life I worked on planes with a top speed of 400 mph: Our de-ice system was pretty simple. The leading edge of the planes had inflatable boots that filled with hot air from the exhaust."
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c7o0id | How can TVs playback content with a framerate thats not dividable by the refresh rate? | Technology | explainlikeimfive | {
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"text": [
"The most common is playing 24 fps movies on 30 fps TVs. It converts 24 frames per second into 29.97 frames per second. Roughly speaking, converting every 4 frames into 5 frames plus a slight slow down in speed. The first 2 output frames are original. Output frames 3 and 4 are a mix of input frames 1, 2 and 3. Output frame 5 is input frame 4. URL_0"
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c7odlu | once somebody takes the cap off of a honeycomb, how to they extract the honey? | Technology | explainlikeimfive | {
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"text": [
"They put the whole comb in a special kind of centrifuge and use centrifugal force to extract it."
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c7p9p9 | What is "PCIe 4.0" and what advantages does it have over its predecessor? | Technology | explainlikeimfive | {
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"text": [
"PCIe (Peripheral Component Interconnect express) is a standard for a type of socket in computers, generally on the motherboard, that other components like graphics cards, hard drives, wifi cards, etc, use to connect. PCIe 4.0 has a transfer rate of 16GT/s (Giga transfers per second), which is double that of PCIe 3.0 and has lower power requirements. PCIe 5.0 went up to 32GT/s for a total of 63GB/s with a 16 lane configuration, and PCIe 6.0 went up to 64GT/s, for 128GB/s with 16 lanes. PCIe 3.0 was released in 2011. PCIe 4.0 was released in 2016. PCIe 5.0 will be released sometime this year, and PCIe 6.0 in 2021."
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c7qfxy | What is a boltzmann brain? | Can someone elaborate? | Technology | explainlikeimfive | {
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"text": [
"It is an example of the general idea that if you wait long enough anything that is even the slightest bit possible will eventually happen. The general concept is not very different from the idea of the perhaps better know thought experiment of having infinite monkeys randomly bang on typewriters and having one of them by pure chance end up with the script to Shakespeare's Hamlet. If you have some random arrangement of stuff like a deck of cards that you continuously shuffle, the longer you keep at it the more likely it becomes that the cards per pure random chance will end up in the correct order. Usually we don't worry about stuff like that too much. The bit about shuffling a deck of cards will only result make it likely in timespans that compare with the expected lifetime of the universe. A human brain complete with memories and everything has a lot more variables than a deck of cards, but if you get right down to it, if you arranged every atom exactly as the atoms in your brain are arranged now it would be an exact copy of you. In the vacuum of space there is some constant low level random fluctuation going on of particles being created and destroyed. In the general view of things this equals out to more or less nothing. However there is a non-zero chance that randomly enough stuff might come into existence to actually matter on a big scale. It is sort of like the idea that a glass of water might randomly heat up by spitting out an ice-cube. In theory possible but you would never actually expect it to happen. When you wait long enough stuff that is merely extremely unlikely becomes inevitable given enough time. When taking the really long view. Eventually stuff that seems impossible will happen. The Boltzmann brain is an example of an absurd thing that could happen given enough time. Matter randomly assembling by pure chance into something that works like a human brain complete with memories and everything. A consciousness coming into existence full formed out of nothing at all. In a universe that goes on forever it seems like an inevitable result that such impossible things might happen eventually, which seems pretty stupid. Even worse is the idea that if Boltzmann brains are not only valid things that might occur at some point in time but actually inevitable things given enough time, how can you tell that you personally are a human being with a past that came into existence through evolution acting on arrangements of clumped together stardust and not just some random arrangement of matter which spontaneously came into existence a moment ago complete with memories of having been a human being for years. You can't really know if you are a person or just a brain floating in space with false memories of being a person. Both are possible. What might give you an existential crisis is the question of which is more likely. When talking about forever some really frighting stuff may result.",
"Looking for ways to explain the begining of the universe, Boltzmann came up with the idea of a primordial soup in which random fluctuations would create the universe. The thing is... It ended up infinitely more likely for fluctuations to create just brains with all our memories than our universe, thus birthing the Boltzmann brain thing.",
"Basically the idea that a soup of particles could randomly form a functioning consciousness given that the universe is old and huge. The idea is that this brain randomly hallucinating our whole existence is more likely than our actual existence under the laws of thermodynamics."
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c7qrxl | Why are the intellegence of video game NPC (specifically shooters) not seeing improvement or getting worse? | I've noticed that unlike graphical fidelity which we can see a steady improvement over the years, the intelligence of NPC and enemies in games such as Halo and Ghost Recon series are either just bad as always or getting worse. NPC teammates in the Ghost Recon series is just known to be not great and your squad in Halo 5 is worse than what we had back in Reach. The enemy NPC in all these games also don't seem to have improved that much over the years. Why can't we see a good progress when it comes to NPC programming? Edit: I think some of you are misunderstanding my question, I’m not asking why NPC enemies are unable to easily beat the players, I’m asking why we still can’t get a smooth experience when it comes to playing with NPC teammates and enemies. This is evident in games such as Ghost Recon Wildlands and Halo 5 where people have complained about the NPC in those games. | Technology | explainlikeimfive | {
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"I watched a video on what makes games fun for players. And it turns out we do not like it when a game is too hard, when it feels unfair. The AI has got so much better over the years but they give us a sense of being the main character",
"There's another thing and that people actually hate the unpredictability. Eg, if your goal is to kill everyone on a level, you don't want there to be a smart guy hiding in a closet. If he sees you coming and engages in a game of cat and mouse, that'd be even worse. They tried better AI in Oblivion and removed it, because it resulted in NPCs fighting with each other, deserting their posts, or doing various weird things. Many of those weird behaviors had quite human reasons for them -- but it's not that fun when the local smith gets randomly murdered, or a quest giving NPC randomly wandered into the forest.",
"It's very difficult to make the AI a convincing human player, and the effort wouldnt pay out well enough. I'm more an expert on strategy games but here we go: When you try to make the AI better it will simply outclass humans easily because it just minmaxes everything. If you make it worse it will feel very dumb. If you want to make it human-like you need to study what kind of mistakes humans make and then synthesize these into your AI one by one. This is a lot of work, because you also have to balance out how often they should do mistakes, and when the game updates you will have to rewrite the AI completely maybe."
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c7rx4d | How did we learn to distinguish between toxic and non-toxic plants and mushrooms, and especially treat some toxic plants so that they become edible? | E.g. some beans, almonds, false morels, seeds of certain edible berries. | Technology | explainlikeimfive | {
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"It was given to sheep, goats, dogs and if it were safe for them we would try. Trial and error",
"There's a safer method of testing foods before eating them. Each step requires waiting a day or two for any reaction to form before moving on, but first it's handled, touched to the lips uncut and cut, then a small nibble, then gradual introduction into diet if it's good. That keeps everyone out of the outhouse at the same time.",
"Effectively by trial and error. Some groups around the world still do this. Their method is to feed the oldest members of the family or community first with the new food to see what happens next. If they're alive after a few days then they give it a pass.",
"one factor many people are missing is starvation: in times of scarcity, you take a lot more risks and try different methods of preparing food since the alternative is starving to death. Take the case of olives. We didn't keep trees around for eating, but because we learned to make oil from them. (the rest is speculative) They are high in fat, and were grown plentifully (the oil wells of ancient civilization) but taste horrific if not brined. Imagine a grain shortage - so you have to feed your animals something. Creative farmers probably mixed the discarded pressings of the olive to up the caloric load of the feed. To water down the taste, they would have literally soaked the olives. Seeing the animals taking to them, a starving farmer might have given one a nibble and realized - hey, these aren't great, but we can eat them. What can I do to make them better? Accidents are another form. So, back to the olives. They were everywhere. Brining was also a common method of food preparation. I could imagine a huge vat of vegetables being brined in a house next to the olive press. A careless worker knocks a couple of olives into the brine. A few months later, someone scooping out the last of the veggies notices a shriveled round thing and tentatively takes a bite to try to figure out what it is. It tastes okay, but not great, so they approach the best briner in town to figure out how to improve it - some lye some ash, and the modern olive would be born. Mushrooms: After watching wildlife closely, you notice that they only eat specific mushrooms. Your family spends generations eating those mushrooms and you become adept at picking them out, knowing where they grow and avoiding the others. In a time of scarcity, or maybe just clumsiness, you pick a similar looking mushroom and give it a try. Maybe it kills you, and future generations avoid it, or maybe you get lucky and its tasty - it's then added to the menu.",
"I see a lot of interesting explanations in this topic but I share a question with OP: how did we discover wqys to make initially inedible or bad tasting food, edible. I am thinking specifically of olives, which I heard are absolutely horrible right off the tree and need to undergo quite a complicated proces before they are edible (and then still are an acquired taste for many people)."
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c7w7g0 | How do Radio Waves work? They have always been around? | Technology | explainlikeimfive | {
"a_id": [
"eshw25x",
"eshwaz6"
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"text": [
"Radio waves are electromagnetic waves, just like light is and X-Rays are. Radio waves have a larger wavelength than visible light, and they have always existed as a form of radiation just as every other electromagnetic wave has. They weren't used as a method of communication until the early 20th century though. We generate them using antennas that have high currents oscillating in them.",
"Radiowaves are a form of electromagnetic radiation. This means that they have 2 components, an electric wave and a magnetic wave (the electric wave induces a magnetic wave and vise versa). Radiowaves are just EMR with really long wavelengths and thus low frequencies. Increase the frequency (and decrease the wavelength) and you will get microwaves, do that some more and you get infrared waves, some more and it becomes visible light, some more and it becomes ultraviolet, a little more and it's considered xrays, and some more and you get gamma rays. Radiowaves would have been around for as long as there have been charged particles which as far as we know is about 13.8 billion years (IIRC) as we don't know what happened before the start of the big bang. When a radiowave is transmitted it can excite the electrons in a conductor which can induce a current in said conductor. This is the principal behind data transmission where we can change the intensity of the radiowaves from between some amount of 0 and send binary data over long distances at the speed of light."
],
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5,
4
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|
c7wq0r | Why can't we use nuclear fission to fuel rockets? | Why can't we harness enormous amount of energy generated from nuclear reaction to fuel rockets, since, conventional rocket fuel costs a ton? I get that, there would be threat of radiation but it would be very efficient and a big step towards space exploration. Is there any solution in theory that hasn't been tried yet? | Technology | explainlikeimfive | {
"a_id": [
"eshyux6",
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"text": [
"[We can.]( URL_0 ) But putting a nuclear reactor on a rocket is a horribly bad idea. And a nuclear rocket would still use rocket fuel, it would just ditch the oxidizer.",
"> I get that, there would be threat of radiation That is one of the big reasons it isn't done. Throwing nuclear dirty bombs around is bad form. > Is there any solution in theory that hasn't been tried yet? We can't know what we don't yet know, but any nuclear rocket requires carrying significant amounts of highly radioactive material onboard, and that is the deal breaker."
],
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"text_urls": [
[
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[]
]
} | [
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c803bh | What is Gradle? | Can someone explain to me what is Gradle and the purpose of it? | Technology | explainlikeimfive | {
"a_id": [
"esiphpt"
],
"text": [
"Gradle is an automated build system. It takes a change that you made in the source code and builds a new version of the software, bringing in all the 3rd party libraries and modules dependencies, and runs tests that you define to make sure your software is doing all the behaviors that it supposed to be doing."
],
"score": [
7
],
"text_urls": [
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c80ryh | How do Captchas know if I'm a robot or not? | Technology | explainlikeimfive | {
"a_id": [
"esisd2d"
],
"text": [
"IIRC a captcha collects data such as mouse movements and speed of input and such. I may be wrong though"
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
c80x61 | What is the difference between Inkjet, Laserjet and Matrix printer? | Technology | explainlikeimfive | {
"a_id": [
"esisjhe"
],
"text": [
"An inkjet printer uses ink and is better for low volume (amount) printing and is normally better for home owners. A laserjet printer uses toner (dry powdery substance that gets electrically charged [stuck] to paper). This printer is much better for high volume (amount) printing and is seen much more in office settings. A matrix printer is most simile to a typewriter, meaning that it has a ribbon or sheet that is struck by a series of “hammers” against the paper."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
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|
c829he | Can someone explain blanks, squibs and live ammunition and their uses? | Technology | explainlikeimfive | {
"a_id": [
"esj6049",
"esjdst0"
],
"text": [
"Blanks are fake bullets. They make noise, but no bullet comes out of the gun. Squibs are packets placed under clothes, triggered by SFX people to make it look like you got shot. Live ammo... Well, real bullets come out, and you don't need squibs... Edit: As another poster mentioned, even blanks can be dangerous. They don't have a bullet, but they do blast hot gas and possibly a paper or plastic wad out of the barrel. If you get hit with the blast or the wadding, it can be dangerous. Back in 1984, [an actor shot himself in the temple with a blank,]( URL_1 ) [ and died from the injury that it inflicted.]( URL_0 )",
"Your normal round has four things that are needed to be a true round. You have the [primer]( URL_0 ) which is struck by the firing pin to ignite the powder, the [casing]( URL_7 ) which holds everything together, the [gunpowder]( URL_6 ) which creates the needed gasses and pressure, and the [bullet]( URL_3 ). Most people call the entire assembly the \"round\". •[Blanks]( URL_4 ) consist of the primer, the case, and the powder, but don't have a bullet (the edges are crimped so that the powder can't fall out). They are mostly used for training. Most guns have \"[blank firing adapters]( URL_1 )\" (known as BFA's) that blow gas back into the gun so that there aren't cycling issues that come with the lack of a bullet. •A [squib]( URL_2 ) isn't a round, and more of an event. When a round, for whatever reason, doesn't go off properly the bullet can get stuck in the barrel. Most shooters probably know this as an \"audible pop\". If another bullet is fired, the next bullet and extra gas has nowhere to go and can destroy the gun barrel or action. It's essentially a dangerous blowback caused by a blocked barrel and too much pressure inside the gun. •[Live ammunition]( URL_5 ) is just a standard round."
],
"score": [
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"text_urls": [
[
"https://ew.com/article/1994/10/14/jon-erik-hexums-fatal-joke/",
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"https://c8.alamy.com/comp/BX0J25/view-of-primer-end-of-a-number-of-50-bmg-cartridges-BX0J25.jpg",
"https://www.rangerjoes.com/GetImage.ashx?Path=%7E%2FAssets%2FProductImages%2FA3077.jpg&maintainAspectRatio=true",
"https://youtu.be/qcHJajwkWyM?t=94",
"https://d2bz5a3a8phucs.cloudfront.net/wp-content/uploads/2018/07/223-556-non-cannelure-6-e1527269718117.jpg",
"https://www.perfectshotllc.com/wp-content/uploads/2017/11/100_4785.jpg",
"https://image.sportsmansguide.com/adimgs/l/5/584328i_ts.jpg",
"https://s3.amazonaws.com/s3.timetoast.com/public/uploads/photos/9585068/gunpowder-pile.jpg",
"https://www.petersoncartridge.com/media/1092/first-taper.jpg"
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|
c82mv2 | How does closed captioning work for live television commentary? | Is there someone writing it as the show goes along like in a courtroom? And if they mess up, how long is the delay before being broadcasted? | Technology | explainlikeimfive | {
"a_id": [
"esj9ws2"
],
"text": [
"Yes. Someone (called a stenographer) is usually typing along as the people talk. So there's about a three-sentence delay between what someone says and when it shows up in the captioning. If they mess up, it usually just gets put up as-is, and you might see active backspacing, because it's more or less a live-feed. You also need to understand that stenographer's computers don't have letters like yours, but sounds (I learned this on LegalEagle). So the typos look different *and* they usually type faster."
],
"score": [
9
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"text_urls": [
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c83uzf | How are so many nuclear weapons regularly tested if we know what consequences they cause? | Technology | explainlikeimfive | {
"a_id": [
"esjn7hd",
"esjltla",
"esjvb1d"
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"text": [
"There are not regular test of nuclear weapons today. Non of the major nuclear powers have tested there weapons for a long time. The last US test was in 1992, Russia(USSR) in 1990, UK in 1991, France in 1996 and China in 1996, & #x200B; After that only India and Pakistan in 1998 and North Korea 2006-2017 have tested nuclear weapons. For Pakistan and North Korea it was there first test ever so the needed for validate there designs. India had a single test back in 1974 to send the message to China and Pakistan that thy could developed nuclear weapon if it was needed and after So the statement that there is many regular test today is not correct. & #x200B; Most test in not to determine the destructive effect of nuclear weapons even if there was test back in the 1940-60 for that but to validate design of nuclear warhead and to show that they will work even if stored for a long time. Since the Partial Nuclear Test Ban Treaty back in 1963 there have not been any test above ground so no test after that is to determine effect of nuclear weapons on the surrounding area but to show that the design works as expected.",
"Testing serves two main purposes: (1) to measure the effectiveness of new designs, and (2) to measure the effectiveness of aging weapons that have been in storage for years.",
"The only nation that has tested nuclear weapons in the last 20 years is North Korea, and has done so only 6 times since 2006. This has been done in a highly calculated fashion, RNK is a very strange country with a strange power structure and shouldn't necessarily be expected to do things that are in it's best interest. RNK has not participated in a range of multi national treaties that have worked to ban nuclear testing and nuclear development. Iran may seek to develop and test a nuclear weapon since the current US president has chosen to violate treaty arrangements with them and imposed a host of sanctions with no treaty justification. (This is of course moronic for a host of reasons and doesn't benefit either party.) Iran may see developing a nuclear arsenal as the only way to get the US to honor it's own agreements."
],
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|
c87ybi | How is it that large LCD flat panel displays have gotten so cheap?. I remember hearing 20 years ago that the LCD displays were created from a single crystal, but this can't be possible for the 100" panels now available. What advancement in manufacturing made this possible? | Technology | explainlikeimfive | {
"a_id": [
"esknxek",
"eskjio6",
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"text": [
"In a lot of cases it's not a major breakthrough, just progressive improvements in the process and tools. If you start out with 1 panel in 10 being defective, you're wasting a lot of time and materials and have to price the other 9 to compensate. Think about how common \"dead pixels\" were 10 years ago. Defect rates were so high that consumers were even willing to accept minor ones. Then as you continue to refine your process that number becomes 1 in 30, then 1 in 500, and as the amount of panels wasted to defects drops so does what you need to charge just to recoup costs. Couple that with economics of scale (sell more - > charge less) and you see substantial price drops.",
"> I remember hearing 20 years ago that the LCD displays were created from a single crystal, The entire foundation of how LCD TVs work is rotating tiny sections of liquid crystal. If they're \"a single crystal\" it's not in the sense you're probably thinking. > What advancement in manufacturing made this possible? Competition, mainly, with scale and improvements in manufacturing playing a much smaller role. With China and India competing about who can churn out the cheapest factory workers, factories competing on who can pay them the least, shipping companies competing on who can spend the least fuel and crew to move your TV around the world, retailers and website competing on who will take a marginally smaller profit margin to get more costumers, and demand for LCD TVs dropping now that most people either have something \"good enough for them\" or choosing to wait for AMOLEDs to become affordable, prices were bound to drop.",
"Simply put mass manufacturing. As you make more you get better at it and more efficient and the price keeps coming down. Of course during that process the manufacturers also start reducing their vendors and soon they are producing everything on their own or there's only one major player producing everything. Earliest example would probably be the Ford Model T. Look at the price and production section to see how prices went down every year starting from $ 850 in 1909 to $ 290 in 1925.",
"One reason the prices have dropped is there is actual competition now. Previously there was a group of companies price fixing the prices of LCD/TV's. This kept the prices artificially high. & #x200B; \" Did you buy a computer notebook, computer monitor, or big-screen TV anytime from late 2001 to 2006? If you did, odds are that you paid too much for it because of an international criminal conspiracy to fix the prices of the LCD (liquid crystal display) panels used in these products. Recently, AU Optronics Corportation—the largest Taiwanese producer and seller of LCD panels—and two of its former top executives were sentenced for their roles in this conspiracy. The company was ordered to pay a $500 million criminal fine, and the executives each received three years in federal prison. AU Optronics is the eighth company convicted as a result of a joint FBI-Department of Justice (DOJ) Antitrust Division effort to uncover this worldwide price-fixing conspiracy.\" & #x200B; & #x200B; [ URL_0 ]( URL_0 )"
],
"score": [
29,
11,
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"text_urls": [
[],
[],
[],
[
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]
]
} | [
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|
c88g98 | why can people who aren’t able to see properly IRL, see in VR? | I just saw a post about a 93 yo woman (who could barely see and only in her peripheral vision) using a VR headset and the post said that it turns out she could see properly in VR. So she experienced Google Earth and various places and she was mesmerised. It was also mentioned that she hasn’t seen colours like that in years. There were also multiple comments about people who could see in VR but not IRL. What is the explanation for this? | Technology | explainlikeimfive | {
"a_id": [
"esksyp2",
"esl524e",
"eslu4sv"
],
"text": [
"VR technology isn't some miracle that can let blind people see color. What is most likely is that the old woman has something that makes absorption of light via her lenses difficult. For example, cataracts, clouding of your eyes' lenses as you grow, can do this and lead to blurry or unfocused vision that might appear faded. VR, which is actually very close to your face, only simulates the appearance of distance and depth, much like a hyper-realistic painting. This is the best explanation I can come up with.",
"There is a lot of things VR compensate for as a side effect of the technology. If you need lots of light, it can be set plenty bright. If you need saturated colors, it can be set plenty colorful. If you can only see sharp at a specific distance (short or long), it can put the entire field of view at that distance. That is, if you don't artificially make depth of field blur, it does not have any blur. Glasses instead can't increase the amount of light, or make it more colorful, and they can move the focal distance closer or father apart, but they can't put everything in focus at once. That's also why if you have vision problem and can't find your glasses, looking at your smartphone screen through the camera actually allow you to see clearly!",
"Screens are very close to your face with VR obviously, and only simulate depth. People who are nearsighted can generally see in VR pretty clearly, even without glasses. In terms of her perception of color, it’s possible the headset she used had OLED panels (like the Vive, Rift, or Quest). OLEDs have much better contrast than LCDs or LEDs which will make the colors ‘pop’ much more."
],
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6,
3
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c8al1v | How do satellites distinguish between all the billions of signals emitted by all the devices in the world? | Technology | explainlikeimfive | {
"a_id": [
"esllqd1",
"eslb4bl",
"esl9itp"
],
"text": [
"Very few of the devices that people use day-to-day communicate directly with satellites (aside from GPS, but it only receives data broadcast from the satellites to every GPS devices). If you do not own a boat or an airplane, you likely also do not own any device that can transmit to a satellite (this is actually true even if you do own a boat or airplane, but you're more likely to find satellite phones and similar devices in these places). You of course *can* buy such a thing, but they're expensive to operate because two-way satellite communication has very limited bandwidth. Satellite TV can send lots of data because it sends the exact same data to every device listening. Rather than working like a whole bunch of individual telephone calls, it's essentially just one big loudspeaker aimed down from space.",
"Satellites work on certain frequency ranges that differ from those used by most devices on the ground - usually satellites use higher frequencies and don't overlap to much with those used on the ground. Additionally, most of the devices on the ground are not even close to powerful enough to send a signal that could get picked up by satellite, those signals are not much more than background noise that gets filtered out easily. To get around the power requirements and to reduce overall signal noise for everyone often enough signals are somewhat targeted/directed at the satellite so it becomes easy for it to distinguish the strongest signal that is meant for it. Also, certain encoding techniques are used so the satellite can read the 'signal ID' to discern whether the signal is meant for it or not.",
"They pay attention to the signals that are aimed right at them. Very few of the billions of devices in the world have enough power to be picked up by a satellite 23,000 miles up."
],
"score": [
7,
5,
3
],
"text_urls": [
[],
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} | [
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|
c8bxto | what does it mean when a game engine is tied to the fps? why is high fps sometimes casuing problem? | playing ff14 atm and the devs said any fps above 90 fps causes game enging problem problem and apparently causing out of bound issues and stuff, how is that related to fps? isnt that more like model collision? | Technology | explainlikeimfive | {
"a_id": [
"eslndsf",
"eslm39l"
],
"text": [
"So tying a game to frames per second means that certain actions are updated on a per-frame basis. The simplest way to think about this is, consider a ball that bounces up and down. To create this we need to track acceleration, velocity, directional, and current position. Given we have finite resources, we can not track this in a continuous manner. Instead we need to update all these on a schedule. We could set this schedule to be every **X** milliseconds. Alternatively, we can tell the engine to update the numbers every time a frame is rendered. The issue with this, is that as frames increase or decrease, we change how often we update numbers. In this toy example that isn't necessarily a problem. I will give two real world examples where this does become a problem. The first is Skyrim. Their engine is tied to FPS. In fact, when you go over 60 FPS everything tends to go berserk. But a real issue is with attacking and damage. Attacks occcur and then there is a \"cool down\" before another attack can happen. At higher FPS, these attacks can occur faster than at slow FPS. On the flip side, the player can take far more damage in the same \"wall clock\" amount of time. So in a way the game does not have \"damage per second\" but rather \"damage per frame.\" So at 90 FPS, you can take 50% more damage per second, because there's more frames for this damage to occur in.\" It doesn't work exactly like that, but you get the picture. The other example works exactly like that is Call of Duty Advanced Warfare. One of the weapons in that game was a laser cannon that dealt damage every frame. This is fine on consoles which all run the same frames per second. On PC however many players have 100+ FPS. Console generally run between 30 and 60 FPS (I believe AW was locked to 30 FPS.) This meant on PC this laser cannon did over three times the damage it did on consoles. The moral of the story? Don't use frames to updated your game.",
"I know one example is that some games have physics engines that are tied to FPS so if a game were to be forced to run faster, the originally intended animations and movement of objects can get all crazy and accelerated."
],
"score": [
43,
5
],
"text_urls": [
[],
[]
]
} | [
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"url"
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c8d6oe | Why do wine bottles usually use corks instead of lids or caps? | Technology | explainlikeimfive | {
"a_id": [
"esm1fa9",
"esmg4uj"
],
"text": [
"Yes, it is to do with the fermentation process and allowing oxygen to enter the bottle as it ages. Fermentation is what we call it when the yeast (living organisms) change the grape juice by eating the sugar and creating the alcohol and flavors of the finished wine. *Many wines develop undesirable aromas under anaerobic –no oxygen– conditions; a small amount of oxygen will eliminate those trace* [*thiol compounds*]( URL_1 ) *responsible for the aroma of rotten eggs* [*or burnt rubber*]( URL_5 )*. Oxidation products also react with the* [*red anthocyanin molecules*]( URL_4 ) *from the grapes to create stable pigments in red wine.* *The way a bottle is sealed will directly affect how much* [*oxygen passes into the wine*]( URL_2 ) *each year. That will directly affect the aging trajectory and determine when that wine will be at its “best.”* [* URL_0 *]( URL_0 )",
"It's all marketing. Our preconceived notion of a \"good\" bottle of wine is a bottle with a cork, and a screw cap doesnt fit that notion. I know that in the US markets some wines are sold with cork bottles, while in other parts of the world that very same wine is sold with a screw cap. Ultimately it makes no difference"
],
"score": [
27,
4
],
"text_urls": [
[
"https://winefolly.com/review/chemist-explains-corks-matter-storing-wine/",
"https://winefolly.com/review/where-wine-flavors-come-from/",
"https://winefolly.com/tutorial/the-truth-about-oxygen-and-wine-aging/",
"https://winefolly.com/review/chemist-explains-corks-matter-storing-wine/*",
"https://winefolly.com/update/young-wines-better-than-old-wines/",
"https://winefolly.com/tutorial/33-bizarre-wine-flavors/"
],
[]
]
} | [
"url"
] | [
"url"
] |
|
c8d83e | what is the difference between Hz and FPS? | I have seen some phones advertised as having 60 Hz display and the phone being ultra smooth. But recording and watching videos in a higher FPS is also a measure of smoothness right? | Technology | explainlikeimfive | {
"a_id": [
"eslyapn",
"eslxxfu"
],
"text": [
"Hz is just more general. Hertz is a generic unit of frequency. The number of something per second. For example sound waves are measured in Hz, the number of oscillations per second. Or for a CPU, the Hz is the number of clock cycles it does per second. So Frames per second can also be expressed with Hz. In the context of say a video, FPS and Hz are the same thing. Although you might have a display that's 60Hz, i.e. it updates 60 times per second, but you might be watching a 30 FPS video on it. So while the display refreshed 60 times a second, the video only outputs a new frame every other screen refresh.",
"Hertz (Hz) is the SI unit for frequency measured in 1 cycle/second. It is the unit used to measure the refresh rate of the monitor (i.e., how often the monitor updates the image displayed). A 60Hz monitor, for example, will refresh 60 times/second. Frames-per-second (FPS) is the number of frames that your GPU will output per second. So 60fps means that your GPU is outputting 60 frames each second. FPS is also a measure of cycles/second, so it could be measured in Hertz. However, we often don't do this because using the same generic unit to refer to the number of frames as well as refresh rate can be confusing. Having these two numbers mismatched can lead to something called [screen-tearing]( URL_0 ), where the screen will display two or more partial frames (i.e. the top half might be a new frame, and the bottom half an older one)."
],
"score": [
4,
3
],
"text_urls": [
[],
[
"https://en.wikipedia.org/wiki/Screen_tearing"
]
]
} | [
"url"
] | [
"url"
] |
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