AFAIK As Far As I Know
AFK Away From Keyboard
AKA Also Known As
ASAP As Soon As Possible
ATM At The Moment
BBL Be Back Later
BBIAB Be Back In A Bit
BBS Be Back Soon
BRB Be Right Back
BRT Be Right There
BSOD Blue Screen of Death
BTW By The Way
CTD Crash to Desktop
FFS For Sake
FYI For Your Information
IDK I Don't Know
IRC Internet Relay Chat
IIRC If I Recall Correctly
IRL / RL (In) Real Life
IMHO In My Humble Opinion
IMO In My Opinion
LOL Laugh Out Loud
LTNS Long Time No See
NM NeverMind
NP No Problem
OMFG Oh My <censored> God
OMG Oh My God
ROFL Roll On the Floor Laughing
ROFLMAO Roll On the Floor Laughing My Ass Off
RTFM Read the <censored> Manual
STFU Shut The <censored> Up
TBH To Be Honest
TTYL Talk To You Later
WB Welcome Back
WTF What The <censored>

AoE Area of Effect
Alt Alternate Character
Att Attributes (Character statistics)
Carebear Someone who doesn't care for Player versus Player Combat
DD Direct Damage
Dev Game Developer
DT Downtime
ETA Estimated Time of Arrival
GM Game Master
IC In Character, Interstellar Correspondent
KoS Kill On Sight
LVL Level
MMORPG Massively Multiplayer Online Role-Playing Game
Mob Monster or Beast, Mobile Object
NDA Non Disclosure Agreement
Newbie starting player, one that doesn't understand the game mechanics yet
Noob starting player, one that doesn't understand the game mechanics yet
NPC Non-Player Character
Nube starting player, one that doesn't understand the game mechanics yet
OOC Out Of Character
P2P Pay to Play
PC Price Check
PK Player Killer
PvE Player versus Environment, Player versus Entity
PVM People vs Mobs
PvP Player versus Player
RPG Role-Playing Game
TTYI Talk to You Ingame
WTB Want to Buy
WTG Way To Go
WTS Want to Sell
WTT Want to Trade

Att to raczej Attack...

ATK to attack.

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