TicTacToe, is a pencil-and-paper game for two players, X and O, who take turns marking the spaces in a 3×3 grid. An early variant of Tic-tac-toe was played in Roman Empire, around the first century BC. It was called Terni Lapilli and instead of having any number of pieces, each player only had three, thus they had to move them around to empty spaces to keep playing. The game's grid markings have been found chalked all over Rome. However, there is some evidence to suggest that Tic-Tac-Toe could originate back to ancient Egypt.
The different names of the game are more recent. The first print reference to "noughts and crosses", the British name, appeared in 1864. The first print reference to a game called "tick-tack-toe" occurred in 1884, but referred to "a children's game played on a slate, consisting in trying with the eyes shut to bring the pencil down on one of the numbers of a set, the number hit being scored". "Tic-tac-toe" may also derive from "tick-tack", the name of an old version of backgammon first described in 1558. The U.S. renaming of noughts and crosses as tic-tac-toe occurred in the 20th century.
In 1952, Tic-tac-toe became the first known video game, OXO (or Noughts and Crosses) for the EDSAC computer. The computer player could play perfect games of tic-tac-toe against a human opponent.