AFAIK As far as I know
AFK Away from keyboard
AKA Also known as …
ASAP As soon as possible
A/S/L Age/sex/location
ATM At the moment
BRB Be right back
BTW By thе way
CY, CYa See you!
FYI For your information
GL Good luck
GTG Got to go
HF Have fun
IMHO In my humble opinion
JK Just kidding
LOL Laughing out loud
NP No problem
OMG Oh my god!
PLS Please
RDY Ready
ROFL Rolling on the floor laughing
RTFM Read the fucking manual
SUXX It Sucks!
TNX, 10X Thanks
W8 Wait!
WTB Want to buy
WTH What the hell?!