This is not a chat room. This is a Forum or a Message Board if you prefer.
-Mod= Moderator. Basically a forum’s Cop. Mods love Coffee, donuts, and distributing infractions.
-CR= Coffee Room. According to Yeshivaleaks there is also a secret Tea Room which is a VIP subforum where only the fat cats can post.
-Thread=topic/subject. There are many different types of threads but here generally they’re either Halachic, Informative, Socratic, Inquisitive, Trollish, For_the_lols or rebyidd23-ish.
-Post=message.
-Troll=a basement-dwelling creature that haunts message boards and creates havoc for the lols.
-Joseph= Notorious multi-headed troll which lurks deep in the forgotten depths, awaiting the the moment it may finally inflict its terrible agony upon others.
-PBA: Popa_Ben_Abba. A cynical jewish woman and VIP Poster.
-OP: Original Poster.
-@<nickname>: The poster whose message/post you’re replying to.