AFK [MUD] Abbrev. for “Away From Keyboard”. Used to notify
others that you will be momentarily unavailable online. eg. “Let's
not go kill that frost giant yet, I need to go AFK to make a phone
call”. Often MUDs will have a command to politely inform others of
your absence when they try to talk with you. The term is not restricted to
MUDs, however, and has become common in many chat situations, from IRC to
Unix talk.