ELI5: What does it mean for a bomber plane to be nuclear weapons capable? Is dropping nukes that different from dropping conventional bombs?

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physically, kinda.

Bombs are not ‘standard’, in that any bomb can fit into any mount point. Many will fit into most, but each needs their own specific mount point, and hookup (for sensors if guided, weight-appropriate release etc) so an aircraft needs an appropriate mount.

Politically, VERY MUCH SO.

Nuclear weapons are very strictly regulated, in their use. they need specific authorization codes, they need multi-person release authorization. So most of the time, the thing that makes them ‘nuclear weapon capable’, is the authentication gear to meet the multiple codes needed to release it, and to enable the weapon by turning off the failsafes.


To be “nuclear capable” an aircraft has to have a specific arming system installed that the operators can control in flight. It’s typically just an extra switch in the cockpit. Plus a whole bunch of other bits elsewhere that deactivate the nuclear failsafes. Mostly electronic.


I worked as a munitions loader on USAF fighters and bombers, and was responsible for converting the B1B, from a nuclear capable aircraft to a non nuclear aircraft (I did all the conversion work).

In short, the only real difference is in the programming of certain computers and in some cases, hardware (such as wiring….it isnt replaced or removed, but cut/disconnected).


We have had air crashes with nuclear bombs and they didn’t go off because they are not armed in till just before release.
If you could do it on pylons under wings and belly would you even want to and risk a accidentally release.


In the WW2 era the biggest bomber aircraft could carry 20,000 kg of bombs but they were designed to hold racks of bombs that individually weighed 500 to 1000 pounds. Early atomic bombs weighed 10,000 to 20,000 each so while a plane might be able to carry that weight in theory, in actuality the nuke might not fit. Bomb doors might not be big enough, dropping just 1 can cause balance issues, etc.

Nuke capable used to be a distinction that the aircraft could handle very large/bulky bombs or sometimes just a single bomb. Later on it also meant they possessed specific nuke monitoring sensors


Eli5 – If a car speedometer is inaccurate, is the odometer also inaccurate?

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I love how almost no one is even addressing the question, they’re all just pointing out that all speedometers are inaccurate and describing why.

This is a difficult question because modern cars often do things in different ways than they used to, but generally speaking yes, the speedometer and odometer are driven by the same mechanism. Up until maybe the ‘90s or 2000s this was always a physical cable that leads from the transmission to the dashboard. There is a small output shaft on the transmission that spins a gear at a certain speed, which spins the cable and is measured by the speedometer. In theory you are supposed to replace the gear if you do something that would make the reading inaccurate, like changing the tire size. Anecdotally I have a car with a failing speedometer cable and when the speedometer isn’t spinning the odometer isn’t spinning either.

Eventually these physical cables started to be replaced by an electronic sensor on the transmission that read the rotation of the gear and sent that information over wires to the speedometer, which had a motor in it to mimic how a cable-driven speedometer works. Again in these cars the speedometer and odometer are driven together, I had a car with a flaky electronic speedometer and once again the odometer would stop updating whenever the speedometer wasn’t working.

But lately there have been other new changes. Digital odometers (and also digital speedometers) have replaced mechanical ones, as far as I’m aware they use exactly the same concept of having a sensor read a gear driven by the transmission but where that information goes and how it’s used is much more complex. But since the information is coming from the same place via the same mechanisms I don’t see any way it could be any more accurate or precise.

So yes, with possible exceptions the speedometer and odometer are almost always driven by the same data so any discrepancy in one will be in the other as well.


Edit: a lot of great points are being made in the replies, I guess I should emphasize that the newer and more high-tech a car is the harder this question is to answer. Nowadays there are so many different ways to do things and so much processing done to the raw speed data before it even reaches the speedometer or odometer. So there are certainly going to be exceptions to the way I described things working, that’s just traditionally the way it’s done and it doesn’t really make sense to take speed and odometer readings in different ways since that data is inherently correlated.


If your speedometer is off because your wheels don’t have exactly the air pressure they’re supposed to have (or similar), then your odometer will also be off.

However, your speedometer measures revolutions over time, so for a speedometer the time measurements can also be off (and for older cars that don’t use a digital speedometer the whole mechanism is by nature less accurate than the odometer).


The speedometer is generally off by a percentage, so yours showing 70 when you’re actually doing 68 should show 35 when you’re actually doing 34.

In the EU there is a law that says that a speedometer is not allowed to show a speed *below* your actual speed, and cannot show a speed more then 15% *above* the actual speed.

Most cars I’ve owned have been out by around 6-8% — when I’m actually doing 100km/h they are showing 106 to 108km/h. (For this reason I tend to sent my cruise control to be about 8% higher than the speed limit).

Manufacturer will add this error intentionally so that they definately do not show a speed *below* the actual speed — they would be a fined a very very large sum of money if that were to happen.

As for the odometer, I can only surmise that that too will be inaccurate by the same amount. You can probably test this yourself — when driving at 60mph (by your speedometer), time yourself for 5 minutes and see if your odometer has moved on exactly 5 miles. Or 15 minutes and 15 miles. Use cruise control to maintain your speed (if you have it).


All speedometers are inaccurate. So, in order not to be sue, company always overestimate speed by 3%. So if you see 100 kph it’s really 97 kph (check with your phone gps app). The risk of getting a ticket is lower and companies don’t risk to be sue because the speedometer lied to you.

And in the meantime, they save 3% on warranty because when your car just go over the guarantees mileage, let say at 100,000km, in reality your car only has 97,000km and is still under warranty.


Lots of modern cars in the UK deliberately misreport the speed, telling you you are going faster than you are, by about 2mph. This is due to a law that makes an offence to report the speed as slower than you are actually going, and since the speedometer can’t be guaranteed to be 100% accurate this is a trick to prevent them illegally reporting the wrong speed.


ELI5 Why isn’t more antibiotics injected rather than oral?

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Not really, because if you inject something it goes into your blood, and blood goes everywhere. But giving antibiotics orally is very much less invasive than IV. if treatments are not invasive, then patients are more likely to take them.


The injection is more complicated, you need some training to do it correctly, and there is also the risk of infection.

Most antibiotics are taken at home by the one with the infection that likely has no medical training. Swallowing a pill is simpler. Injection yourself or having someone else do it is not simple, it requires training to do it in a safe way. The result is there are very few medical interventions that are done at home that require injection. If there is a requirement there is some training involved.

So injected antibiotics are used in a hospital setting if the oral variant is not appropriate. There you have trained people that can handle it.


Because injections need to be performed by medical professionals and that would require people to make a LOT of trips to hospitals or GP’s and it’d put a huge strain on those facilities.

Also, the more effort it takes to do something, the higher the odds people will quit doing it before it’s safe to quit.


Purely from a medical standpoint its a good idea.

But it’s not practical in the real world


Probably be a bit less convenient if the treatment lasts for 5-7 days or longer and having to get that person into a setting to make the injection daily, or twice daily. Doable but rather impractical for most people.

If there is a serious infection (like blood sepsis), then the patient will be hospitalized and IV antibiotics given.


That is not how antibiotics work. Well, at least not how all of them do.

If you have a pneumonia (infection of the lungs) you will still get the antibiotics i.v. (intravenous) or p.o. (per os – oral) because the active substances go through the bloodstream to the bacteria.

If you have an infection of the gastrointestinal system you will most likely receive antibiotics p.o., and if you are lucky and your type of bacteria is susceptible to non-absorbable antibiotics than you will get one of those. For example C.Difficile can be treated with Vancomycin which does not get absorbed from your intestines and works only inside the gastrointestinal tract. This will help you not get problems with the bacteria in your skin and mucosa causing mycosis (infections with fungus).

To sum it up: it does not matter how you give the antibiotic (almost never, an exception I have mentioned), it will sadly almost every single time destroy the good bacteria reaching it through the bloodstream.


Side note: there are other options nowadays and we are trying to use local antibiotics. For pneumonia we can also do inhalative therapy. For urinary infections we have some antibiotics that get excreted in urin and for other types of incetions (skin, eyes, ears) we have drops or ointments.


ELI5: in the military, what are NCO’s, how do they differ from normal officers, and why do some countries not have many of them?

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In general, an officer is a soldier who has authority over other soldiers. In modern militaries, a commissioned officer is an officer who is formally granted that authority by a government.
This document granting such authority is called a commission, as in the officer is literally commissioned by the government to lead. A non commissioned officer is an officer who was not expressly commissioned, but has been promoted to the office.

What this means is that commissioned officers are, usually, trained at an academy, commissioned, then assigned a duty. These officers are generally trained for leadership or specific roles *before* they do them. Non commissioned officers enlist, are assigned a duty, then promoted to leadership as they prove competency/gain seniority.

Commissioned officers are the “educated” academy folks, the ones who are trained to lead, command, or perform specialized jobs such as fly a fighter plane, or command a platoon of tanks. Non commissioned officers are from the common soldiers, the enlisted troops. They start at the bottom, they do the “grunt work,” are the ones “on the ground,” and make up the bulk of the military.

This is with regards to a modern national military. Older militaries were very different in not just organization, but in their function and purpose.

While not part of the original question, anyone interested should read the other posts regarding warrant officers, another important part of military leadership.


NCOs are sergeants (or petty officers or whatever). They are enlisted personnel who have lots of experience. This is in contrast to officers, who in most militaries join directly as officers after having undergone some sort of advanced training.

NCOs are important in that they can basically help soldiers learn how to be better soldiers. An officer trying to help an infantryman is like an MBA trying to help a programmer: they can give high-level advice about tactics and motivation and stuff, but can’t give good advice on how to pack things in your backpack for best balance and accessibility in the field, or which field rations taste best, or that the #3 engine needs more oil than the others.


Officers handle the big-picture red-tape stuff and issue orders, while NCOs relay the orders to the troops, supervise, adapt, and accomplish the task in accordance with the commander’s intent.

NCOs are generally much more experienced than officers at ground-level, and are familiar with possible undesirable outcomes for a given plan.

At a company level, it is the unwritten job of the senior NCOs to tell the much more junior officers why their plan is stupid (behind closed doors), and help them amend it in a way that still achieves the intent of the order. The junior NCOs take the finalized plan and direct their men to execute it.


From an episode of *Hornblower:* “The Petty Officer’s job is not to do the task — it’s to see the task is done.”

Watch *Band of Brothers* to see how WWII Army responsibilities and authority developed and were assigned.

Speaking very generally, the Officers are assigned a mission and various resources (people, equipment) to perform that mission. The mission may be to operate a supply depot involving hundreds of people and thousands of tons of stuff. The mission may be to occupy a hill top and hold it against enemy action. Obviously, one Officer cannot do this alone, and has subordinates to complete the many tasks involved.

Here’s where the division occurs — the Officers are concerned with the Goal, the NCOs are concerned with the Method of achieving that goal. A good Officer will give clear goals to the NCOs. The NCOs will train the unit personnel on how to reach that goal — weapons training, medical, cammo, transportation, and more. In turn, the NCO tasks the officer to get the material needed for the training.

Once ready and in the field, now the Officer directs the general situation (take that hill) and specifies methods (tactics) to be used (flanking, mortar fire, coordination with other units). The NCOs then act with their teams to carry out the overall plan. The NCOs are on the front line and can react to local situations. The Officers are a bit further back, seeing a wider view (enemy approaching our left flank!) and give orders accordingly.

You trust your NCOs to lead you through situations you can handle (training, resources). You trust your Officers to put you in situations that are worthwhile to risk your life (tactics serving a strategy).


The US bases everything off small unit leadership. We get a task from officers and we carry out those task in the way we see fit.
Many nations don’t utilize an NCO corps Because their training is more abput listening to direct order vs figure it out as you go.
Every NCO in the US is essentially a Cpt. Jack Sparrow.


eli5: what does a ‘think tank’ do?

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Think tanks are companies that produce ideas. They employ, depending on their industry of focus some or all of the following: experts with industry experience, scientists, researchers, data analysts, consultants, marketers, writers, and PR people. Some exist to do genuine research and advance the intellectual state of their industry in good faith, for the greater good. Others are “legitimizers for hire”, cherrypicking facts and data to back up an existing claim or agenda.


A think tank is usually an organization using different scientists, researchers and analysts to provide analysis, recommendations and research papers for specific topics, often on a strategic, long-term level.

Often think tanks specialize on a certain topic (military, economy, foreign politics for example), and in some cases have a clear political colour.



originally they were a way to connect high level technical expertise with government. They attempt to identify and solve problems for government as a separate 3rd party. The first think tank was the Rand Corporation, itself the offspringof the US military’s Research ANd Development department, under which the Manhattan project was carried out. The Rand corporation worked on the theoretical side of nuclear weapons and the cold war, and is the origin of the term game theory among other things. While initially not intended to be partisan, they’ve increasingly become ways to theorize and formalize potential policy under the guise of academia. Effectively many of them are the other side of lobby culture now


The main political think tanks in D.C. operate like sitting governments.

A particular ideological faction will employ people who filter in and out of the different branches of the US government and they will conduct, or pay, for political science research, write policy papers, and draft legislation. When a new president with shared ideology gets elected, they will pick cabinet executives and management from those think tanks and they will then start the process of trying to pass legislation that was developed in the think tank, or use their papers to develop executive action.

Following what think tanks are doing is what political insiders inside the beltway do every day because they have a huge influence on future legislation and they keep people from the operational management levels of the executive branch in the loop so they can hit the ground running when a transition happens. The same goes from the transition from one Cabinet level official to the next inside the same presidential administration.


They’re private bodies that conduct research into (existing or proposed) government policies and then work to disseminate the results to the public, the media and the government. They almost always have some specific political goal in mind, which can be something noble like “reduce CO2 emissions” or “improve cancer treatment”, or something selfish like “increase the profits of the tobacco industry” or “get the Evil Bastards Party elected”. Often they aren’t very honest about their goals. They tend to get their funding from some combination of rich people, businesses, charities, political parties and governments. Some of them actually hire respected academics and do serious research, while others just do the bare minimum to make it seem like there is scientific support for their preferred policies.


ELI5: How do maggots get into the fridge if food has been left there too long with the power off?

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Not to gross you out, but the eggs are already in the food. It’s really no different than a little bit of protein from regular chicken eggs. But food isn’t typically “sterile”. Like those potatoes and carrots in the fridge? They used to be in dirt. For most things, as long as you don’t eat too much, you’ll be fine and your stomach acid and intestines just take it in stride.

But this is one of the reasons you don’t want to eat raw flour. Milling it into flour doesn’t kill bacteria.


Leave fruit in a sealed container. Watch it rot into a nest of fruit flies.

The eggs are already on the food. Normally, it doesn’t matter, your digestive system destroys them and/or consumes them and/or excretes them, so it’s really not that big a deal.

But if you let them grow, that’s what happens. Everything you eat, no matter how sterile you think it is or what food standards it conforms to, has had an insect of some kind land on it at some point in its life, and if it laid eggs, those eggs wait for the ideal conditions before they hatch. Fortunately, those ideal conditions are normally long after a human would ever touch that food, when it rots.

Unless your food was produced in an entirely insect-free laboratory-sterile environment (something that we’ve found almost impossible to do on Earth… even the “simulate Mars” or “attempt to leave in a bubble” experiments are often contaminated by living insects getting in), it’s going to have something on it, whether that’s bacteria, mould, eggs, parasites, or whatever else.

And, to be honest, trying to grow food in such a perfectly sterile environment is not only incredibly expensive such that you’d never try to do it, but also not conducive at all to growing produce – those insects, bacteria and moulds are a vital part of the process.

It’s one of the biggest problems in space travel: You can say what you want about propulsion, building cities on other planets, powering them from the sun, etc. but the fact is that no human has survived even a day solely on food that has been grown in space (only by sending food to space from Earth). Because it’s almost impossible to grow sufficient quantities due to the expense, very difficult to make them grow well because of the sterility, and propagating food forever more needs enriched soils, nutrients and the same moulds, bacteria and insects.


Others have answered.

They are already on / in the food.

We had an issue years ago at home where some cereal we bought had moth eggs in it and when we opened the plastic packaging we could see the eggs and baby moths moving about.

Out of disgust and stupidly we left the bag open to take pics for a complaint when our cat knocked it off the counter and the content went everywhere. We then had to clean up cereal, egg dust, and moth larvae off the floor. We obviously didn’t get everything as we had an issue with moths in the house for a while afterwords.

In short always keep your food in air tight containers if possible.


If you get maggots in the food they were already there. More exactly the eggs that they came from were already there. Maggots are the larva of flies, another insect also lay eggs that become larva that might look similar but they are long maggots.

The eggs might be there when you purchased the food but they can also get to the food in your house. A fly can lay hundreds of eggs at once. It can also be that there is insects in the fridge that lay the eggs after you close it for the last time.


Most/all fridges have a drain so condensed water can escape.

If you have a fridge full of rotting food all types of bugs will follow that scent.


ELI5: Why does the pitch of American movies and TV shows go up slightly when it’s shown on British TV Channels?

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Movies (and some, but not all modern US TV shows tend to be shot at 24 frames a second)

British TV runs at 50hz thus to fit nicely in with the refresh rate they play the movie at 25fps.

This results in a tiny speed increase, and also audio pitch shifting up ever so slightly.


American TV is 59.94 fields per second, while British TV is 50 fields per second.
Movies are shot at 24 frames per second.
So in order to broadcast a movie:

1. If it’s for British TV, 24 and 25 are so close to each other that you can just get away with speeding up the movie by ~4%. While this gets unnoticed for video, you can hear the change in audio pitch, especially if a song you know is playing in the film. After the 24fps to 25fps speed change, you just double each frame so it’s 50 fields per second.

2. If it’s for American TV you can’t get away with speeding it by 25%. So a process called 3:2 pulldown is used. First you slow it down by 0.1% so you get 23.976 frames per second and then you split every frame into two fields and every second frame into two fields with one duplicated, so you get a 2-3-2-3-2-3.. pattern and with that 59.94 fields per second with only 0.1% speed change.

So why aren’t British TV shows faster when broadcast on domestic TV? Because they are shot at 25 frames per second and then you just have to duplicate each frame to fit into 50 fields per second. While American TV shows are shot at 24 fps.


Me and my girl watch movies over discord, could this explain why she somehow is always drifting ahead of me even though we start at the exact same time? She’s in Australia


When shows are syndicated in the US, I noticed a higher pitch on some channels. This is because they speed up the show slightly to squeeze in more commercials.


beside what has been mentioned here already with FPS differences it may also be another reason that some channels simply show any movie sped up by 10% because that allows you to fit in an entire extra ad break.


ELI5: How do they prepare sand dunes to build roads, houses, and other projects on top of?

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Piles and different foundation setups. There are many kinds you can use actually and correct one is down to what the engineers are experienced in and what the project needs.

But imagine you put two phonebooks together, so that the leafs are neatly laid from both sides evenly. The friction between two sheets of phone book paper is basically nothing, but if you multiply it by 1000, you get lots of friction. And this is how piles work. They are long and have lots of surface area against anything you push them in to, even soft sand. These prevent the foundations on top from moving sideways, or up or down. After this you can connect these to make a raft foundation. This setup is so solid and permanent after it’s natural settling that it can be considered to not move at all. Often you can find a sort of a strange hump near old building development, these were the foundations of the tower crane used for them. They don’t move, but the ground around it will move, so they can become quite pronounced. After the you lay a cast foundation on this all.

But now… How do you do this for something that doesn’t have “foundations” in the same traditional sense. Like a road; no one is driving piles for a road. Well here we start to utilise the natural properties of the ground, or sand in this case.

First you dig ditch, basically with 45 degree slopes on the sides (this is important). Then you place some special fabric at the bottom, fill a layer of sand, then another layer of fabric, another layer of sand… so on and so forth. You are basically creating sand and fabric sandwich composite.

Why fabric? It tends to be soft and fragile, what good does it do? Well consider something like a cotton blanket. Yeah it doesn’t really have shape it’ll compress if you put something on top of it, you can’t build up with it, if you tear it from the side it’ll rip apart. But here is the funky engineering, it doesn’t need to. That an average cotton dish towel, hold it perfectly so it is a plane, and now pull on it as hard as you can. You can’t rip it apart by evenly pulling it. The threads it is made of all share the load equally and therefor they all take very little of it. Anyway back to the sand layers. As we know from playing in a sandbox, loose sand is soft and it flows out under you if compressed. it is like liquid in a way. Right now, remember the properties of the dish rag? How you couldn’t pull it apart? Now lets combine these two. The fabric prevent the whole layered foundation from spreading, the sand prevents it all from compressing. So now you have a foundation that doesn’t want to really move made entirely from fabric and sand. On top of this you build your road. Last question remains: Why 45 degree slopes? Because triangle is the strongest shape, and 45 degrees has the properties of using least surface area (volume of sand or dirt) while having the greatest tringle properties. If you take a perfect square and cut diagonally from point to point, you get a triangle with 90 degree and 2 45 degree angles.

With these methods of piles, fabric, dirt and foundations, you can build anything on just about anything. You could basically even build on water in theory, in an ideal setup. But as we know cows in a frictionless vacuum don’t live for long.


Depends what’s under them.

I worked building roads through the desert. Mostly the dune was scraped flat then some form of grave base was laid down, more layers of gravel then tarmac. You needed a lot! Then you find the dunes move / get blown and you’re forever clearing sand off the road 🙄


Millions of dollars in foundation materials

The burj khalifa used multiple, thick concrete pillars going 50+ metres down into the dunes, with a solid 15m thick slab of thick concrete to act as a foundation.

The weight of all the sand around the pillars keeps them straight, while the final slab is thick enough to support things

This wasn’t your papi’s house by a long shot, it was really a case of “I’m gonna build this here, and if mother nature wants me to fail, she can suck my magnum dong”. Not practical, but the only real option.


If it’s like other beach construction… they go through the sand to bedrock. Usually the sand layer isn’t so thick and it’s easy to move.


One of the key ideas missing from the discussions below is the concept of “buoyancy”.

For sand, the concrete pilings are driven into the (dense) sand, so much of the downward force of the pilings + roadway, the weight, is offset by the upward force of the displaced sand.

Also, there is also a component of the ‘movement resistance’ of sand that also counters the weight of the pilings and roadway, which can unfortunately vanish with the precise ground vibrations, like what occurs during an earthquake, i.e., soil liquefaction. I don’t know the frequency of earthquakes in the desert, but they make life in California a bit *too* interesting.


ELI5: Why is it so difficult for us to just replicate a bird instead of the kind of fixed wing aircraft we have?

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Flapping bird wings are kind of inefficient. They’re great for picking yourself off the ground, but require a lot of energy to keep going

Larger birds, which are still small and light compared to an airplane, achieve flight easier by riding updrafts in the air and gliding, with very little flapping at all.

This is what the fixed wing aircraft replicates. This has added benefits of less turbulence, with the plane not being pushed up by the periodic addition of lift.


Number one reason is there is no need to.

The mechanics and engineering behind a pivoting wing that is also supporting of the weight needed would be complex. Also, the thrust provided wouldn’t compare to that of modern engines.

So more complex with more things to go wrong for less benefit.


It’s not hard…. At the size of a bird. Beyond that, things start to fall apart

Birds wings cannot carry much. There’s this fact of the universe called “the square cube law”. Tldr: if you make something bigger, it’s weight will increase faster than its size. This law is why there aren’t many elephant sized birds. If they got too big, their bones would be too heavy.

We can technically make bird-sized machines, but bird-like wings don’t really scale up well. They get too big, they just can’t support their own weight. In fact, it’s why there aren’t many elephant-sized animals. Most could not handle the weight of being that big

Tldr: Birds just aren’t the best at flying. That goes to aero engineers.


Actually, I know it may not be intuitive, but helicopters fly like birds. Unlike fixed wing aircraft, helicopters manage lift, direction and thrust with their blades, as birds do to their wings. While airplanes handle lift with their wings (and other lifting areas), thrust with the motor and direction with flight control surfaces (e.g. ailerons).

If your question is why don’t we have airplanes which flap their wings: basically we don’t have any kind of material which could handle that kind of forces. Additionally, as others have said, it would be very inefficient.


One thing that hasn’t been mentioned either is that the wing shape of a plane (airfoil) does in fact replicate/is very similar to a birds wing in cross-section.


ELI5: Why does old software get buggy when it hasn’t been updated for a while? Shouldn’t have the same amount of bugs as it was when that version was released?

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Software running on a a totally closed system will not generate new software bugs. Examples might include old-school arcade games, appliances like a microwave oven, and old digital watches.

These systems might show new errors as the hardware gets old and fails in ways the software was never written to handle.

But any software that has to talk to other software will show new bugs over time because the writers of the code could not predict every possible new change.


The software needs to be able to keep up with all the other software that it interacts with.

If you have a moped on a road it works well. What happens when that road becomes a 4 lane highway and suddenly the other mopeds are now cars? Kinda like that.


**Software when new**: “Windows, can I have X, Y, and Z?”
**Windows**: “Absolutely!”

**Software 10 years after last update**: “Windows, can I have X, Y, and Z?
“**Windows, after having just received a new updates**: “I can give you X, but y has been replaced with y1, and Z has been deprecated since June due to safety concerns”
**Software, never written to handle this**: “Error!”


It’s not that the software itself gets more buggy, it’s that compatibility with the libraries and the operating system is lost, so things little incompatibilities might result in small bugs.

One of my favorite examples is that some games used the PC clock speed for the game speed. So modern faster cous result in a game that is unplayable because it’s so fast.


The code that makes up the program is a set of precise instructions. Those instructions only work properly in the environment they were made for. If the environment changes, then the instructions wont work correctly, even if the instructions themselves remain unchanged.

Imagine someone wrote down directions for how to walk from their front door to their bedroom, but really specifically. Like, REALLY specifically. “Take exactly 17 steps forward, then turn 90 degrees clockwise, then take 42 steps, then turn 90 degrees counterclockwise, then climb 27 stairs, then turn 45 degrees clockwise, then reach forward and grasp the doorknob located exactly 22 inches in front of your left hand and 45 inches above the ground, then walk forward 12 steps” and so on and so forth

Now, imagine that those instructions were written years ago, and the layout of the house has changed. They got a new couch so if you walk those first 17 steps as instructed, youll bump into it. They replaced the old door with a new one and now the doorknob is 2 inches higher. If you follow the instructions, youll miss the doorknob.

Thats the general idea. The instructions are the same, but the environment in which those instructions will be executed has changed, so you can sometimes run into problems.