Chess is a chess game on the CDC 6600 computer. The program was continuously iterated on and knew many versions which became progressively better. The game won the ACM North American Computer Chess Championships eight times and the second WCCC in Toronto in 1977. Originally using a Shannon Type B strategy, the game was completely rewritten for version 4.0 to use a Shannon Type A strategy.
The game also ran on PLATO terminals. Version 3.5 allowed players on other terminals to spectate matches in progress.
In 1976, Chess 4.5 won the Class B section of the Paul Masson American Chess Championship, the first time a computer was successful in a human tournament.