Well I was trying to be general because I don't do any real gaming. But for an example, in Warcraft II you could type something in and get more gold. Thats what I'd consider a cheat code, or stuff for consoles. But for stuff like CS online we don't want to be telling people how to cheat/hack. I almost said singleplayer: yes multiplayer: no. But then I thought if you were playing some local lan game with your buddies that would be ok.
So maybe I should say it like this - yes, unless its a violation of the established rules of wherever you are playing.