A:
UL, L, ML, M, MH, H - those are the action types.
UL for panfish, L for panfish maybe small bass, ML for bass, Medium for bass and walleye, MH for bass, walleye, carp, pike, muskie and catfish, and heavy for the bigger stuff. Actions tend to also be a tighter stiffer rod and the lighter ones have a lot more flexibility, so you want to be careful using those on bigger fish.