Away From Keyboard  

Often abbreviated AFK, this is a common gaming term for anytime that a player is not at their keyboard and able to respond. It may be short (a few minutes for a bio (or bathroom) break, to leaving a character logged in for hours.

Many games have a command you can use to display an AFK tag above your head so other players know you ar enot there, and in some games this tag appears automatically after a certain number of minutes of inactivity.

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