Out of character

From WoWWiki

Out of character (OOC) indicates something said or done by the person playing a character, not the character itself. OOC speech is often interjected when explanations are required that cannot be provided in character. It is often denoted by the use of "OOC:" preceding the text or by placing the text in double parenthesis "(( ))".

OOC: I have to go to the bathroom.

(I have to go to the bathroom)

((I have to go to the bathroom))

The third version is the most preferred, as it is easily recognizable from normal speech. In the game, OOC talk should be limited to /party or /tell. Too much OOC chatter in /say tends to annoy roleplayers.