ooc or OOC is a commonly used acronym in Cybersphere, and means Out Of Character. Anything said to be OOC comes from the player themselves, rather than their character. As a command, there are two variants:
@ooc - will put your character Out Of Character, effectively immune to anything in the game world and "not there". You will not be able to move whilst in this state. Please note that any ongoig effects will still impact your character, and it is considered very poor form to go OOC to avoid conflict; you will not be able to do so if you have been involved in combat recently.
ooc - Say something OOC, whilst not actually going out of character yourself. This can also be used in the format "ooc : emotes", to emote OOC.
See also: Help:IC