Want to play chess with your friends on Facebook? Probably not! But if you do, there is a way — a secret chess game built directly into Facebook's chat function and Messenger app. Simply open up a conversation with a friend and type "@fbchess play" to start a game. Then you can just use standard algebraic notation to move your pieces, prefacing every instruction with the command "@fbchess." So, "@fbchess Pe4" would move your pawn (P) to square E4, for example.
Confused? Type "@fbchess help"
You can also type "@fbchess help" for instructions, but here are the basics: K is for king, Q for queen, B for bishop, N for knight, R for rook, and P for pawn. If you need to specify which piece you're moving, you can add its location to the command. So "Nbd2" will move the knight in the b file (the vertical column) into square d2. Use the command "x" to take a piece (e.g. B2xc5 will have your bishop in the second rank, or horizontal row, to square c5); the command "=" to promote a pawn to a queen (e.g. e8=Q); and the command "0-0-0" to castle.
You can also use "@fbchess resign" to end a match, show you and your friend's vital statistics with "@fbchess stats," and pick which color you start with by typing "@fbchess play white" or "@fbchess play black." (If you don't specify your color will be assigned automatically. As usual in chess, white goes first.) We're not sure how long this functionality has been available, but the subreddit /r/chess noticed it back in December last year. Has it been around longer than this? Feel free to scold us in the comments — or just find someone to play chess with instead!