Ply (game theory) consists of one proposed move by the machine and one anticipated reply by the opponent"). In computing, the concept of ply is important because one ply corresponds to one level of the game tree. The Deep Blue chess computer which defeated Kasparov in 1997 would typically search to a depth of between six and sixteen plies to a maximum of forty plies in some situations. Ply (game theory) In two-player sequential games, a ply is one turn taken by one of the players. The word is used to clarify what is meant when one might otherwise say "turn". The word
Human–computer chess matches first game (Deep Blue – Kasparov, 1996, Game 1), the first time a reigning world champion had lost to a computer using regular time controls. However, Kasparov regrouped to win three and draw two of the remaining five games of the match, for a convincing 4–2 match victory. In May 1997, an updated version of Deep Blue defeated Kasparov 3½–2½ in a highly publicized six-game match. Kasparov won the first, lost the second, and drew the next three. The match was even after five games but Kasparov was crushed in Game 6. This was the first time a computer had