what are the main back parts/region so i can properly choose excersises for a split?

so i just switched to upper lower upper lower (4 days a week) and im now planning exercises for each day and i wanna know the main regions/parts of the back so i can properly plan the excersises

what i mean my perts is like on chest we have lod,mid and upper pecks,and shoudlers we ahev front side and rear,but ive heard its not that simple of back


only ones i know are lats and traps


are the rest like just lower back and mid back (since traps are at the top so id guess that is upper back,and lats are kinda side back if that makes sense)


so is it just traps,lats,mid back and low back or i am missing something??


please help