Professor Alexander "Sandy" Shafto Douglas CBE (born May 21, 1921) is a British professor of computer science, credited with creating the first graphical Computer game OXO (also known as Noughts and Crosses) a tic-tac-toe computer game in 1952 on the EDSAC computer at University of Cambridge.

Douglas attended the University of Cambridge in 1950. In 1952, while working towards earning his PhD, he wrote a thesis which focused on human-computer interactions and he needed an example to prove his theories. At that time, Cambridge was home to the second only stored-program computer, the EDSAC or Electronic Delay Storage Automatic Calculator (the first being Manchester University's "Small Scale Experimental Machine" or SSEM, nicknamed "The Baby", which ran its first program June 21, 1948). This gave Douglas the perfect opportunity to prove his findings by programming the code for a simple game where a player can compete against the computer — OXO.

The rules of the computer game are the same of a regular Tic-Tac-Toe game (human player against the computer). The control device used as input was a rotary dial (like the ones in old telephones). The output was showed in a 35 x 16 pixel cathode ray tube display. This game turned out to never be very popular since the EDSAC computer was only available at the University of Cambridge and it was not possible to install it and play it in other places (portability).

Douglas' project was a success and became the very first video game and graphical computer game, but it was also one of the very first (albeit primitive) applications of true artificial intelligence. The computer's moves in reaction to the player move was not random or pre-determined, but entirely made at the computer's discretion. OXO is often overlooked for its accomplishments in artificial intelligence as the study of AI didn't become a valid science until 1958 when scientist John McCarthy coined the term.

Trivia

• Alexander Sandy Douglas' thesis was a success, earning him his PHD and starting his career in science, however he would never again program another video or computer game.
• Although OXO was the very first video/computer game, it was almost completely overlooked at the time. There was only one EDSAC computer in existence, which was housed at the University of Cambridge and never made accessible to the public.
• The code for OXO was retained as a tech demo for the EDSAC's capabilities.