Computer chess built in by the evaluation function and pruning/extension rules began to match the best players in the world. It turned out to produce excellent results, at least in the field of chess, to let computers do what they do best (calculate) rather than coax them into imitating human thought processes and knowledge. In 1997 Deep Blue defeated World Champion Garry Kasparov, marking the first time a computer has defeated a reigning world chess champion in standard time control. Computer chess programs consider chess moves as a game tree. In theory, they examine all moves, then all counter-moves to those moves,
Human–computer chess matches Michael Adams 5½–½ in a six-game match. While Adams was criticized for not preparing as well as Kasparov and Kramnik had, some commentators saw this as heralding the end of human-computer matches. Kramnik, then still the World Champion, played a six-game match against the computer program Deep Fritz in Bonn, Germany from November 25 to December 5, 2006, losing 4–2 to the machine, with two losses and four draws. He received 500,000 Euros for playing and would have received another 500,000 Euros had he won the match. Deep Fritz version 10 ran on a computer containing two Intel Xeon CPUs