Tic-tac-toe is a two player game that takes turn marking spaces on a 3 by 3 grid, and the objective of the game is to place three connecting marks in a horizontal, vertical, or diagonal row.Tic-tac-toe is a fun game that you can play any time and anywhere as long as you have a piece of paper, a pencil, and an opponent. Tic-tac-toe is a zero sum game, which means that if both players are playing their best, that neither player will win. However, if you learn how to play tic-tac-toe and master some simple strategies, then you'll be able to not only play, but to win the majority of the time. If you want to know how to play tic-tac-toe, then see Step 1 to get started.