IBM Deep Blue

Deep Blue was a chess-playing computer developed by IBM. On 11 May 1997, the machine won a short 6 game exhibition match (not a world title match) by two wins to one with 3 draws against world champion Garry Kasparov after Kasparov made a remarkable blunder (for a world chess champion) in the opening of the last game. Kasparov accused IBM of cheating and demanded a rematch, but IBM declined and retired Deep Blue. Having won his earlier match with Deep Blue, he was nevertheless ahead in the total of 12 games with the computer by 6.5-5.5.
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