Tic tac toe is a paper and pencil game in which players take turns drawing Xs and Os on a grid similar to a pound sign. The point is to get three Xs or Os in a row horizontally, vertically or diagonally.
The game board consists of two vertical lines and two horizontal lines that cross to create nine spaces on the board. One player chooses Xs and the other chooses Os. Each player only adds his shape to the board.
The first player chooses any open spot and draws his shape. The players then alternate adding their shapes. Players often place their shapes to block the other person from winning. If any player gets three of his shape in a row, he wins. Not all games of tic tac toe end up with a winner.