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
Deep Blue (chess computer) the two racks that made up Deep Blue is on display at the National Museum of American History in their exhibit about the Information Age; the other rack appears at the Computer History Museum in the "Artificial Intelligence and Robotics" gallery of the Revolution exhibit. Reports that Deep Blue was sold to United Airlines appear to originate from confusion between Deep Blue itself and other RS6000/SP2 systems. Feng-hsiung Hsu later claimed in his book "Behind Deep Blue" that he had the rights to use the Deep Blue design to build a bigger machine independently of IBM to take Kasparov's rematch