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Zugzwang made its first moves in 1989. It won the bronze medal in the 1990 Computer Olympiad, and won the Paderborn (human) Championships in 1991. In the last [[WCCC 1992|Computer World Championships in Madrid 1992]], Zugzwang, running on a system consisting of 1023 T800 transputers, finished second and was undefeated without playing the eventual Champion, [[ChessMachine|ChessMachine Schroeder]]. In 1993 Zugzwang had its first victory over a grandmaster. In 1994 Zugzwang was completely rewritten from OCCAM to C (about 20,000 lines of code) and is now portable to a large spectrum of machines including [[SPARC]], SGI, [[DEC Alpha]], [[i860]], [[x86|486]] and [[PowerPC]]. In this year's Championships, Zugzwang will run on a GC-Powerplus distributed system (based on the PowerPC) with at least 96 processors. The [[Opening Book|opening book]] contains about 130,000 moves and 1MB [[Transposition Table|transposition tables]] are used per processor. Zugzwang uses [[Brute-Force|brute-force]] [[Alpha-Beta|alpha-beta]] search with [[History Heuristic|history tables]] and [[Killer Heuristic|killer heuristics]]. The program searches about 3000 [[Nodes per secondSecond|nodes per second]] per processor on a PowerPC. The search is performed by distributed processors using a distributed algorithm based on the [[Young Brothers Wait Concept]], which gives good results even if as many as 1000 processors are used. In this case the system calculates moves more than 400 times faster than a sequential system.