Tic-tac-toe is a classic board game consisting of a 3 by 3 square grid. Two players choose one symbol each (X or O) and alternate moves, marking their choice on an empty square on the board. The object of the game is to get three of the same symbols in a row, either vertically, horizontally or diagonally, before your opponent. The player who reaches this condition first wins the game. If all squares on the board are filled and no player gets the required sequence of symbols, the game ends in a tie. Tic-tac-toe is a simple game, easy to learn and ideal to play anywhere, whether with friends, family or even alone.