[eMGm4D0zgUAVXc7]

Try Anki, a spaced repetition flashcard software: https://en.wikipedia.org/wiki/Anki_(software)

It is intended for memorizing things, but the fact that it forces you to divide knowledge into pieces small enough to fit on a flash card also helps to organize it.

And you can have different card stacks in Anki, so there also is categorization of knowledge.

Cf. the "Zettelkasten", a physical flashcard system which is actually intended at organization, not memorization: https://en.wikipedia.org/wiki/Zettelkasten

Anki can be used to emulate that digitally.

[Noumenon72]

I just switched IDEs/operating systems, so I'm using Anki to help me learn that Cmd + Shift + Z is revert changelist and so on. When I'm waiting for something to compile, I tap Anki and let it reinforce my memories that were about to expire.