Here, only the type really matters.
Skirt: A distance away from your print it makes a ring a few lines thick to purge old filament to prime the extruder. HIGHLY RECOMMENDED TO USE INSTEAD OF "NONE"
Brim: Exactly like Skirt but this TOUCHES your prints so that they don't separate from the bed as often. ALSO PRETTY RECOMMENDED
Raft: Makes a thick, slow, wasteful, costly, stupid platform under your whole print. DO NOT USE