Diving deeper in the rabbit hole of hashcat, hash extracting, crypto and decrypting
I recently found myself trying to understand and modify some hash extract scripts, and I realized that I need to go much deeper in the rabbit hole of crypto to understand them and hope to contribute to solutions such as hash extract scripts on the long run.

Does anyone have advice in terms of books or fora to go deeper? With deeper I mean going from using the tool towards understanding the different encryption types, how they are mixed for common applications.
In my case I am especially interested crypto wallets and their encryption types. How hashes are extracted from wallet files and how does hashcat and other tools like JtR know if a password is a hit? Is there some formats or encoding they are looking for?
How is cracking optimized, e.g. shorter hashes in some cases?
Any tips on where to start this deep dive and journey down the encryption/decryption hole are appreciated.