Slang, Informal Words and Expressions in SMS or Social Networking

Sometimes when you chat, in sms or social networking (facebook, twitter, etc.), someone writes abbreviation words, and you don't understand what it means.

The following lists are commonly abbreviated words and the meaning,

ASAP As Soon As Possible
ASL Tell me your Age, Sex and Location
B4 Before
bbz Babes
BFF Best Friends Forever
BRB Be right back
BTW By The Way
CMIIW Correct me if I'm wrong
FB Facebook
FFS For fuck's sake
FYI For Your Information
GM Good Morning
GN Good Night
gr8 Great
GTFO Get the fuck out
IDK I don’t Know
IMHO In my humble opinion                             
JK Just Kidding
K Okay
kk Okay
kl Cool
L8 Late
LMAO Laughing my ass off!
LMFAO Laugh my fu*king ass off
LMK Let Me Know
LOL Laughing out loud
M/F Are You Male or Female?
OMG Oh my God!
plz Please
ROFL Roll on floor laughing!
RTFM Read the fucking manual!
SD Sweet Dreams
sry Sorry
Tnx Thanks
TTYL Talk to you later
TY Thank You
WTF What The Fu*k