What function do subfolders under Windows folder (%windir%) have?

Question

Hello.
There are many folders under %windir%, such as appcompat apppatch assembly bcastdvr. So what function do they have? There seems to be no official document to describe them.
Thanks!

Answer 1

One or more of these links may be useful:

https://en.wikipedia.org/wiki/Environment_variable

https://renenyffenegger.ch/notes/Windows/dirs/Windows/index

https://www.youtube.com/watch?v=Ahxnq3ohwX4

.
.
.
.
.

Please remember to vote and to mark the replies as answers if they help.

On the bottom of each post there is:

Propose as answer = answered the question

On the left side of each post there is /\ with a number: click = a helpful post
.
.
.
.
.

Answer 2

All folders cannot be detailed
But some are explained in MSDN , like assembly for example : Global Assembly Cache