Newbie Question on Raid descriptions

Just a newbie question on some raid descriptions especially in Lordaeron.

Can someone explain or put related discussion link regarding some raid descriptions like:

Prio , Ress, Aim , PS (other have addtion like 20+10 or 20+5 something like that) etc., im still confuse if i can roll the mentioned item.

Thank you!

Join date 2019 and you don't know?

Prio = Priority. Mostly means only the mentioned classes are considered MS the specific item. E.g. "Assassin/Ret prio on https://wotlk.cavernoftime.com/item=50706" would mean Rets/Assassin Rogues would roll first, other DPS classes after.
Res/Ress = Reserved. If it drops, the leader takes the items in question for himself or somebody else (assist/friend). Reserved items aren't rolled.
PS = https://wotlk.cavernoftime.com/item=49908
P = Patterns
O = https://wotlk.cavernoftime.com/item=47556s
BoE= Binds on Equip, occasionally shortened to "B" in adverts.

BOP res for a ToC25 run would mean BoE's, Crusader Orbs and Patterns that drops would be reserved.