OXO (or Noughts and Crosses) is a player vs. computer Tic Tac Toe game which was written by Alexander S. Douglas in 1952 for the one-of-a-kind EDSAC computer at the University Of Cambridge. The single-player "game" was designed for academic purposes — Douglas used OXO on the famous EDSAC to study the "Interactions Between Human and Computer".OXO was the first digital graphical game to run on a computer, and was rather simple to use — the player played against the computer, with output displayed on the computer's 35×16-pixel cathode ray tube. The source code was short, yet played a perfect game of noughts and crosses.
This game provides examples of:
- Match-Three Game: You have to line three naughts or crosses up.
- Unwinnable by Design: The computer never loses.
- Ur-Example: Depending on how you define a Video Game, this may be the first one ever. The next possibility is Tennis For Two.