There is the excellent chess programming wiki, but unfortunately it does error 503 for me right now.

Here is the archive: https://web.archive.org/web/20250302091125/https://www.chessprogramming.org/Main_Page

Main site: https://www.chessprogramming.org/Main_Page

It has some pretty good resources to get started, and all the techniques being used.

EDIT: It's back!!! And Lichess is doing the hosting.