While I prefer to make a positive comment, I think I should share this opinion for the possible benefit of other readers.

In my opinion that review is a complete waste of time.

My statement is not intended in any way as a judgement of Bob Dylan or his work.

Maybe not exactly nostalgia, but there is a term that serves: déjà vu

"The meaning of DÉJÀ VU is the illusion of remembering scenes and events when experienced for the first time." [1]

[1]<https://www.merriam-webster.com/dictionary/d%C3%A9j%C3%A0%20...>

I think this might be a good place to add this reminder:

"Vitamin D is made when UV (more precisely, UVB rays) react with a compound (7-dehydrocholesterol) in the skin. The best rays for UV synthesis have wavelengths between 270–300 nm." [1]

[1] https://www.sciencelearn.org.nz/resources/1313-vitamin-d-and...

270nm is UVC territory. Did you mean 280nm instead?

That is a fair question. This is what I find. [1]

Ultraviolet B UV‑B 280–315

Ultraviolet C UV‑C 100–280

[1] https://en.wikipedia.org/wiki/Ultraviolet

My read is "UVB" is the popular medicine way of saying UV is needed for the body to synthesize vitamin D. It was not considered necessary to point out part of the useful spectrum is in "UVC" territory.

Also kills microbes on surfaces.

You have to start somewhere, and this probably has a place.

Still, having become accustomed to live acoustic music, I find this generated stuff not engaging. Maybe after a few more generations it will get there.

Looking at more of the presentations, we see that this not "How the National Airspace System Works". Rather it is the plan for a next generation system that the FAA hopes to implement.

If you have an interest in this you can see how things are intended to change. A lot of it looks like intended automation of work presently done by controllers. It appears there could be some challenges. For example, weather affects the flow, and what happens when you miss your pushback time?

A series of voice descriptions with animations.

There are many terms and acronyms. I am familiar with the user side of the system. Without this background I would have a hard time following the narrative. Even so I find the descriptions unclear. I don't know of a good overview of the airspace system that does not also explain the rules of operation. I think those become too detailed for casual knowledge.

From the description:

"As you visually dissect the components’ insides, you’ll learn about how they work and how they were made."

We did that in school. Here are the layout photos. Draw the schematics. It was interesting.

I previously heard this called "The Byzantine General's problem". I think there is a lot of discussion under that name.

for example

Back-To-Basic Reading: Byzantine Generals <https://news.ycombinator.com/item?id=13866732>

The Byzantine Generals Problem (1982) [pdf] <https://news.ycombinator.com/item?id=8697029>

These are two different problems, actually! The Byzantine Generals problem is concerned with arbitrary failure: a node may not simply fall offline, but may start sending garbage or otherwise act non-cooperatively. The Two Generals problem is concerned with network reliability and common knowledge: both parties cannot agree on the state of all messages in a system (because you must send one to inform the other party about the status of an older message).

That's the problem with randomness.

The required Dilbert reference: https://dilbert.com/strip/2001-10-25

This is an illustration that grep is a great tool, quick and easy to use.

rather egrep, though

Both grep and egrep are the same executable.

  bash-3.2$ diff `which grep` `which egrep`
  bash-3.2$

Can egrep do lookaheads or behinds? I find it necessary to use positive lookaheads to verify the test words include all the letters marked present but in the wrong location.

I was also curious about this as I use grep -P (for PCRE regexes) if I need to use them. Looking at the manual, lookaheads and lookbehinds don't seem to be supported by regular gnu grep or grep -E, so you do need to use grep -P for them.

https://www.gnu.org/software/grep/manual/grep.pdf

egrep is grep -E.