[Calgon]

RK, DM, CK, SK, RP, ETC.

RK - Revenge Killing; Killing the person who killed you.
DM - Deathmatching; Killing players for non-valid IC reason or OOC reasons.
CK - Character Kill; Killing your character, thus preventing your character from ever playing the server again (You have to register a new name).. in most cases.
RP - Roleplaying; Acting a character on a game as you would do so in real life.. bla..