OXO

OXO was a computer game developed in 1952 by Alexander S. Douglas for the EDSAC computer, simulating a game of Noughts and Crosses, sometimes called Tic-Tac-Toe. OXO is the earliest known game to be displayed on a video monitor. To play OXO, the player entered his inputs with a rotary telephone dial, and the outputs were displayed on the computer's 35×16 dot matrix cathode ray tube. Each game was played against an artificially intelligent opponent.