When I was first learning Linux it was pretty helpful to look at a few random things in /dev and /bin and /etc and learn what they did, whenever I had a few spare minutes.

ZFS has open my eyes to /dev/disk/by-id/. It's the only way when you have many of the exact same make/model/size drives per machine. You will learn by fire the first time you need to determine which drive you need to replace.