Tic-tac-toe noughts and crosses , or Xs and Os is a paper-and-pencil game
Tic-tac-toe noughts and crosses , or Xs and Os is a paper-and-pencil game for two players, X and O, who take turns marking the spaces in a 3×3 grid. The player who succeeds in placing three of their marks in a horizontal, vertical, or diagonal row is the winner.