BK

In text messages and online chat, bk is most often short for "back." Those who ask "When will u b bk?" or exclaim "I'm bk!" are using this abbreviated version of back.

Because back is a popular word in online chat (used to tell others that you're no longer AFK), bk is a popular chat abbreviation. Typing bk instead of back saves chatters two keystrokes, allowing them to resume their game, conversation, or whatever else they were doing more quickly.

A common way to refer to Burger King, a popular burger-based fast food restaurant.

A baseball statistic used to keep track of the number of balks by a pitcher.

A balk is when the pitcher makes an illegal motion, like pretending to pitch with no intention of doing so, to deceive a baserunner. A balk results in the baserunner being awarded the next base for free, so if he was on 2nd base he would go to third base.