Earlier quoted context omitted.
I picked up The Selfish Gene because I was hoping to figure out how JavaScript got so popular.
Any insights?
1) Everyone with a modern, full-featured browser already has it. There's nothing to install. It's the modern equivalent of the built-in BASIC in the early microcomputers.
2) "View Source" lets you see exactly how something was done at the click of a mouse. This is invaluable for learning.
3) Writing it and debugging it just requires a text editor and the browser mentioned before, not some baroque toolchain. You can even modify it and rerun it from directly within the browser, most of which have fairly sophisticated JS debuggers built in nowadays.
4) Rich text, GUI widgets, networking...all that stuff is already baked into the browser cake. You don't need to fool around with a separate libraries.
5) Interpreted, so iterative development is fast.
6) Forgiving (some would say "sloppy"), so beginners don't get overwhelmed with type systems and similar shizzle ("Why can't I just add 1 and 0.5? WTF?") Of course, this also brings problems along with it. No free lunches.
Some other languages, on some platforms, have some of these features, but none to my knowledge has all of them.
For example, Linux systems do come with C, and do have the source code available, but looking up the line of source that produced exactly what you're seeing on the screen in, say, an X program, is a far more involved process than just right-clicking it and choosing "View Source".
Node, in turn, became popular because JavaScript is popular.
That's my take, FWIW.