litchralee @ litchralee @sh.itjust.works

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2 yr. ago

1 - I get that light is flashed in binary to code chips but how does it actually fookin work ? What is the machine emmiting [sic] this light made up of ?

This video by Branch Education (on YouTube or Nebula) is a high level explanation of every step in a semiconductor fab. It doesn't go over the details of how semiconductor junctions work, though. That sort of device physics is discussed in this YouTube video by Ben Eater, "how semiconductors work"

2 - How was program's, OSs, Kernal [sic] etc loaded on CPU in early days when there were no additional computers to feed it those like today ?

When the CPU powers up, typically the very first thing it starts to execute is the bootloader. Bootloaders will vary depending on the system, and today's modern Intel or AMD desktop machines boot very differently to their 1980s predecessor. However, since the IBM PC laid the foundation for how most computers booted up for a nearly four decades, it may be instructive to see how it worked in the 80s. This WikiBook on x86 bootloading should be valid for all 32-bit x86 targets, from the original 8086 to the i686. It may even be valid further, but UEFI started to take off, which changed everything into a more modern form.

But even before the 80s, computers could have a program/kernel/whatever loaded using magnetic tape, punch cards, or even by hand with physical switches, each representing one bit.

But how does the computer decode this binary "machine code" into instructions to perform? See this video by Ben Eater, explaining machine instructions for the MOS 6502 CPU (circa 1975). The age of the CPU is not important, but rather that by the 70s, the basics of CPU operations has already been laid down, and that CPU is easy to explain yet non-trivial.

3 - I get internet is light storing information but how ? Fookin HOW ?

The mechanics of light bouncing inside a fibre optic cable is well-explained in this YouTube video by engineerguy. But for an explanation of how ones-and-zeros get converted into light to be transmitted, that's a bit more involved. I might just point you to the Wikipedia page for fibre optic communications.

How the data is encoded is important, as this has significant impact on bandwidth and data integrity, not just for light but for wireless RF transmission and wireline transmission. For wireless, this Branch Education video on Starlink (YouTube or Nebula) is instructive. And for wired, this Computerphile YouTube video on ADSL covers the challenges faced.

Quite frankly, I might just recommend the entirety of the Computerphile channel, particularly their back catalogue when they laid down computer fundamentals.

4 - How did it all come to be like it is today and ist it possible for one human to even learn how it all works or are we just limited one or two things ? Like cab we only know how to program or how to make hardware but not both or all ?

As of 2024, the field is enormous, to the point that a CompSci degree necessarily has to be focused on a specific concentration. But that doesn't necessarily mean the hard stuff like device physics are off-limits, leaving just stuff like software and AI. Sam Zeloof has been making homemade microchips, devising his own semiconductor process and posting it on YouTube..

Specifically to your question about either software or hardware, the specialty of embedded software engineering requires skills with low-level software or firmware, as well as dealing with substantial hardware-specific details. People that write drivers or libraries for new hardware require skills from both regimes, being the bridge between Electrical Engineers that design the hardware, and software developers that utilize the hardware.

Likewise, developers for high performance computers need to know the hardware inside-out, to have any chance of extracting every last bit (pun intended) of speed. However, these developers tend to rely upon documentation such as data sheets, rather than having to be keenly aware of how the hardware was manufactured. Some level of logical abstraction is necessary to tractably understand today's necessarily large and complex systems.

5 - Do we have to join Intel first or something to learn how most of the things work lol ?

Nope! Often, you can look to existing references, such as Linux source code, to provide a peek at what complexities exist in today's machines. I say that, but the Linux kernel is truly a monster, not because it's badly written, but because they willingly take code to support every single bleeding platform that people are willing to author code for. And that means lots and lots of edge cases; there's no such thing as a "standard" computer. X86 might be the closest to a "standard" but Intel has never quite been consistent across that architecture's existence. And ARM and RISC-V are on the rise, in any case.

Perhaps what's most important is to develop strong foundations to build on. Have a cursory understanding of computing, networking, storage, wireless, software licenses, encryption, video encoding/decoding, UI/UX, graphics, services, containers, data and statistical analysis, and data exchange formats. But then pick one and focus on it, seeing how it interacts with other parts of the computing world.

Growing up, I had an interest in IT and computer maintenance. Then it evolved into writing websites. Then into writing C++ software. Right before university, I started playing around with the Arduino's Atmel 328p CPU directly, and so I entered uni as a Computer Engineer, hoping to do both software and hardware.

The space is huge, so start somewhere that interests you. From the examples above, I think online videos are a fantastic resource, but so can blog posts written by engineers at major companies, as can talks at conferences, as can sitting in at university courses.

Good luck and good studies!

I vaguely recall a (probably apocryphal) story of an early washing machine-sized hard drive that lurched its way across the floor during a customer demo, eventually falling over once the connecting cables pulled taught.

That said, those hard drives did indeed move themselves: http://catb.org/jargon/html/W/walking-drives.html

Can you clarify what style of garage door this is? I'm aware of two main styles: 1) a one-piece door which tilts upward, kinda like a doggy door, and 2) a door with four horizontal panels that rolls straight up on tracks. The first type has giant springs on the left and right, whereas the latter has an axial spring situated just above the door.

In both garage door styles, it should be the case that once the opener is disconnected, the door can be manually lifted and opened, to get the car out during a power cut. If this is not possible, something is wrong and the door itself needs to be serviced first, to avoid cascading issues.

If you do replace the opener, consider models which have a small backup battery, to operate when there's a power cut. The door must still be in working order, but the battery will slowly open the door using the remote control, as normal. Some openers have WiFi connectivity -- which I think is mostly a gimmick, except if there's an app to indicate if I've closed the garage door or not.

In a nutshell: https://terikanefield.com/criminallawfaqs/

I would advise reading that page in order, and in full. It lays a lot of foundation as it goes. There is indeed a call-to-action at the end.

Our system resembles an obstacle course. One consequence of the hard work of people like Thurgood Marshall is taking power away from law enforcement and subjecting law enforcement (including prosecutors) to stringent rules. Federal Criminal Procedure is a full-semester law school course. It is mindbogglingly complex, but keep this in mind: The complexity is to create fairness.

Dear people who want the process to move more quickly: Be careful what you wish for. Giving more power to law enforcement (and prosecutors are part of law enforcement) might bring about the short-term results you want, but is not a good idea in the long run.

In agreement with the other comments, this is indeed a very dense diagram, specifically the right-side. Focusing on that some more, my chief concern is that this novel triangle representation is very easy to misread.

Let's take the dot in the middle which has the arrow with "10M". What would you say the car percentage for that dot is? The axis along the bottom of the triangle is labeled 0 to 100%, and the dot is just to the right of the 50% demarcation. So maybe 52% or 55% seems reasonable, yeah?

But the axis is deceiving: notice how the demarcation are all slanted at the bottom. The dot is actually representing about 42%, since although the axis is marked horizontally, the line which is 50% slopes north-east rather than straight up. You can see the 50% number itself is actually rotated 60 degrees counter-clockwise.

The public transit axis on the left of the triangle has its demarcations tilted clockwise by 60 degrees as well. Only the active transport axis matches the conventional Y axis.

For that UI/UX reason alone, I wouldn't endorse this as a "great" depiction of statistical data. If a diagram can -- intentionally or not -- be used to mislead a casual reader, it's not one we should put up on a pedestal.

I also had a gripe about the successive colors not being consistent for each mode of transport, but that's minor and easily corrected. The tilted axes may require some reworking though.

I think this can be more generalized as: why do some people eschew anonymity online? And a few plausible reasons come to mind:

• a convention carried over from the pre-Internet days to be honest and frank as one would be in-person
• having no prior experience with anonymity or a basis to expect anonymity to last
• they're already a real-life edgelord and so the in-person/online distinction is artificial, or have an IDGAF attitude to such distinctions

IMO, older people tend to have the first reason, having grown up with the Internet as a communication tool. Younger, post-2000 people might have the second reason, because from the events during their lifetime, privacy has eroded to the point it's almost mythical. Or that it's like the landed gentry, that you have to be highly privileged to afford to maintain anonymity.

I have no thoughts as to the prevalence of the third reason, but I'm reminded of a post I saw on Mastodon months ago, which went something like this: every village used to have the village idiot, but was mostly benign because everyone in town knew he was an idiot. One moron in every 5 or 10 thousand people is fine. But with the Internet, all the village idiots can network with each other, expanding their personal communities and hyping themselves up to do things they otherwise wouldn't have found support for.

Coming back to the question, in the context above, maybe online anonymity is a learned practice, meaning it has to be taught and isn't plainly natural. Nothing quite like the Internet has ever existed in human history, so what's "natural" may just not have caught up yet. That internet literacy and safety is a topic requiring instruction bolsters this thought.

I don't have specific movie examples, but the narrow depth of field of a zoom lens would certainly require careful cinematographic considerations. It would be hard to compose a shot that has a typical foreground and background, without accepting that the background might be massively blurred. But I can sort-of see the appeal of having things chronically out-of-focus, as a way of hiding "obvious" details from the audience, until the focus changes and makes the big reveal.

Maybe such a film would be trying to artistically emulate human "tunnel vision", where depth perception is severely reduced.

Obligatory link to Statistics Done Wrong: The Woefully Complete Guide, a book on how statistics can and has been abused in subtle and insidious ways, sometimes recklessly. Specifically, the chapters on the consequences of underpowered statistics and comparing statistical significance between studies.

I'm no expert on statistics, but I know enough that repeated experiments should not yield wildly different results unless: 1) the phenomenon under observation is extremely subtle so results are getting lost in noise, 2) the experiments were performed incorrectly, or 3) the results aren't wildly divergent after all.

As with most things in life, it depends. Two people at different stages of life and career might evaluate the same investment drastically differently, against the criteria of their own priorities.

Years ago, I read the Bogleheads' Guide To Investing which thoroughly discussed, among other things:

• Why people pursue investments in the first place
• The juncture of: time, income, financial timelines, and financial priorities
• How doing almost nothing (index funds) can and does outperform active mutual funds; KISS
• Success criteria, aka not running out of money in retirement

Needless to say, most everyone would prefer a higher rate of return. But the caveat is how much it will cost. Some higher rates of return are almost without cost, such as switching from a brick-and-mortar savings account (0.01% APY) to an online savings account (~4.30% APY). This is almost a no-brainer.

Other investments have fantastic returns but have opportunity costs: buying into large infrastructure can pay huge dividends but take decades to become profitable, tying up the money and sometimes nearly bankrupting the Earl of Grantham. Even still, this could be advisable when viewed in the long-term.

Likewise, some investments have a paltry rate, but carry (almost) no risk of missed payments. Someone looking for a income later in life might be fairly pleased to have a steady stream of inflation-adjusted money.

Even corporations and governments evaluate investments differently than people, since corporeal legal entities aren't mortal and death is optional. Indeed, investment priorities are a lot different for sovereign entities, which cannot declare bankruptcy precisely because of their power to raise taxes.

I hope these examples show that the qualities of an investment -- independent of quantitative measures like return rate or revenue per share -- can be "good" in different ways.

As an aside, a "slow motion camera" and a "high speed camera" are understood to be the same object, being a camera that can capture at high frame rates, to slow down apparent motion in the video output.

I'm reluctant to upvote this, since it's leaving out a lot of rather important caveats about the dataset. This depiction is presented as "the number of aviation incidents between the two giants since 2014 in the U.S. and international waters". Here, "international waters" means the regions of the North Pacific Ocean, north Atlantic Ocean, and Gulf of Mexico, whose airspace services are delegated by ICAO to the United States, administered by the FAA. It's not US airspace, but it's administered as if it was, meaning accident reports get filed with FAA and NTSB, the source of this data.

The other caveat is that the total size of the Boeing fleet flying through FAA-administered airspace versus the total Airbus fleet is closer to 2-to-1, with nearly twice as many Boeing aircraft as Airbus aircraft, using 2018 estimates. This is including all the aircraft which US airliners currently operate, not just the newest ones they've bought in recent years.

Finally, in the reporting parlance, an aircraft "incident" means a non-serious injury event that happened. If major injuries or death occurred, that would be an "aircraft accident". So an incident could include anything like:

• Returning to the airport because of an unruly passenger
• Another aircraft getting too close but not requiring evasive manoeuvres (aka minimum separation violation)
• Overspeeding of the aircraft, such as exceeding 250 knots while still below 10,000 ft
• An engine failure
• A door plug falling off, causing minor injuries to three people but no deaths
• A passenger getting their arm stuck in the toilet while reaching for their dropped phone

What reasons could Boeing aircraft have more incidents? Sure, they might be shoddily assembled. But it could also be a matter of fleet distribution: if Boeing makes more wide-body aircraft than Airbus, and thus carry more passengers, then passenger-related incidents would be higher represented for Boeing aircraft. Suffice it to say, this single graphic isn't giving enough depth to a complicated situation.

I may be confused, but is this a common endeavor? I have used xxd -i before, but have never found its speed of operation lacking.

I didn't include it in my original comment because it's kind of tangential, but carpets also trap rusty staples and -- very strangely -- rusty finish nails. Over six years, my feet have found dozens of these staples and nails twisted within my house's carpet, each of a shape which I have never owned.

I honestly don't know what the previous owners of this place did, but I recently had every shred of carpet ripped out and replaced with wood-look tile. I bought myself some indoor slippers for winter and haven't looked back since.

Beyond that, there's dusting, cleaning windows, sinks, countertops, bathrooms, and probably things I don't even consider.

Of all the items you've listed, I personally rank floors as the most important to clean, followed by bathrooms, countertops, sinks, windows, and finally dusting. These are in order of which are used more frequently and how easily they'd be noticed. A dirty window (on the outside) is rarely dirty enough to outright block the sunlight, but grime on the floor will be tracked into other rooms, worsening the issue. Bathrooms are used daily, so would bother me if they're not at least reasonably seemly.

For keep floor clean, the zeroth step is to prevent dirt and grime from coming in at the onset. A shoes-off policy in the home is probably the most substantial in this effort. That's not to say you have to go barefoot -- although I do think it's quite nice -- since indoor slippers or shoes are an option. The next step would be to rip out all wall-to-wall carpet, if possible. I have a full rant about the drawbacks of carpet, but it will suffice to say that carpet traps dust and dirt whereas hard surfaces like tile or laminate do not.

After that, you may need to identify what exactly is dirtying your floors. If it's loose particulate (eg food crumbs), that's going to need a different solution than if it's loose hairs, which is different than dust or clothes threads. Crumbs or hair might suggest localized sweeping in the kitchen or bathroom will be most effective, while dust or threads suggest you need to adjust your clothes dryer settings, or your central air system needs a new/different filter.

The thing to keep in mind with all this is that grime does not come from nowhere: there is always a source, and the evidence will lead you to what's most effective to keep your home maintained. Even if you conclude that the dust is fallout from the nearby coal-burning power station, there will still be things you can do, such as campaigning for a fossil-fuel free world electrostatic air filters or keeping doors closed when not needed.

It's for this reason I sometimes spell out the Bytes or bits. Eg: 88 Gbits/s or 1.44 MBytes

It's also especially useful for endianness and bit ordering: MSByte vs MSbit

The knot is non-SI but perfectly metric and actually makes sense as a nautical mile is exactly one degree meridian

I do admire the nautical mile for being based on something which has proven to be continually relevant (maritime navigation) as well as being brought forward to new, related fields (aeronautical navigation). And I am aware that it was redefined in SI units, so there's no incompatibility. I'm mostly poking fun at the kN abbreviation; I agree that no one is confusing kilonewtons with knots, not unless there's a hurricane putting a torque on a broadcasting tower...

No standard abbreviation exists for nautical miles

We can invent one: kn-h. It's knot-hours, which is technically correct but horrific to look at. It's like the time I came across hp-h (horsepower-hour) to measure gasoline energy. :(

if you take all those colonial unit

In defense of the American national pride, I have to point out that many of these came from the Brits. Though we're guilty of perpetuating them, even after the British have given up on them haha

An inch is 25mm, and a foot an even 1/3rd of a metre while a yard is exactly one metre.

I'm a dual-capable American that can use either SI or US Customary -- it's the occupational hazard of being an engineer lol -- but I went into a cold sweat thinking about all the awful things that would happen with a 25 mm inch, and even worse things with 3 ft to the meter. Like, that's not even a multiple of 2, 5, or 10! At least let it be 40 inches to the meter. /s

There's also other SI-adjacent strangeness such as the hectare

I like to explain to other Americans that metric is easy, using the hectare as an example. What's a hectare? It's about 2.47 acre. Or more relatable, it's the average size of a Walmart supercenter, at about 107,000 sq ft.

1 hectare == 1 Walmart

I'm surprised there aren't more suggestions which use intentionally-similar abbreviations. The American customary system is rich with abbreviations which are deceptively similar, and I think the American computer memory units should match; confusion is the name of the game. Some examples from existing units:

• millimeter (mm) vs thou (mil)
• meter (m) vs mile (mi)
• kilo (k) vs grand (G)
• kilonewtons (kN) vs knots (kn)
• statute mile (m/sm) vs survey mile (mi) vs nautical mile (NM/nmi) vs nanometer (nm)
• foot (ft) vs fathom (ftm)
• chain (ch) vs Switzerland (ch)
• teaspoon (tsp) vs tablespoon (tbsp)
• ounce (oz) vs fluid ounce (fl oz) vs troy ounce (ozt) vs Australia (Ozzie)
• pint (pt) vs point (pt)
• grain (gr) vs gram (g)
• Kelvin (K) vs Rankine (R; aka "Kelvin for Americans")
• short ton (t) vs long ton (???) vs metric tonne (t) vs refrigeration ton (TR)

I'm afraid I have no suggestions for DoT servers.

One tip for your debugging that might be useful is to use dig to directly query DNS servers, to help identify where a DNS issue may lay. For example, your earlier test on mobile happened to be using Google's DNS server on legacy IP (8.8.8.8). If you ran the following on your desktop, I would imagine that you would see the AAAA record:

dig @8.8.8.8 mydomain.example.com

If this succeeds, you know that Google's DNS server is a viable choice for resolving your AAAA record. You can then test your local network's DNS server, to see if it'll provide the AAAA record. And then you can test your local machine's DNS server (eg systemd-resolved). Somewhere, something is not returning your AAAA record, and you can slowly smoke it out. Good luck!

If I understand correctly, you're now able to verify the AAAA on mobile. But you're still not able to connect to the web server from your mobile phone. Do I have that right?

I believe in a different comment here, you said that your mobile network doesn't support IPv6, and nor does a local WiFi network. In that case, it seems like your phone is performing DNS lookups just fine, but has no way to connect to an IPv6 destination.

If your desktop does have IPv6 connectivity but has DNS resolution issues, then I would now look into resolving that. To be clear, was your desktop a Linux/Unix system?

I can imagine a c/newstotheextreme community, where the rule is to have the title and body of the post be an illogical/absurd extension of the actual news article, which is both screenshotted and linked.

The screenshot provides the funny juxtaposition of an absurd title against the original title, which should be sufficient to prevent people from thinking Minnesota is actually having an ice age.

Let us know if you decide to create that community!