First computer to play in a chess tournament. It played in all 5 rounds of the Massachusetts Amateur Championship in 1967. The chess program was written by Richard Greenblatt of MIT’s Project Mac for the Dec PDP-6 (1200 KHz) computer. It lost 4 games and drew one game (to Conroy). Its first rating was 1269 and first published rating in 1967 was 1493. In the 1967 Boston Amateur, it became the first computer to defeat a human, who was rated 1510. In that tournament, MacHack VI won two games and drew two games. By the end of 1968, MacHack VI’s rating was 1529.