Fritz is a German chess program originally developed for Chessbase by Frans Morsch based on his Quest program, ported to DOS, and then Windows by Mathias Feist. With version 13, Morsch retired, and his engine was first replaced by Gyula Horvath's Pandix, and then with Fritz 15, Vasik Rajlich's Rybka. The latest version of the consumer product is Fritz 18 Neuronal. This version supports 64-bit hardware and multiprocessing by default. History In 1991, the German company ChessBase approached the Dutch chess programmer Frans Morsch about writing a chess engine to add to the database program which they sold. Morsch adapted his Quest program, and ChessBase released it for sale that year as Knightstalker in the U.S. and Fritz throughout the rest of the world. In 1995, Fritz 3 won the World Computer Chess Championship in Hong Kong, beating an early version of Deep Blue. This was the first time that a program running on a consumer-level microcomputer defeated the mainframes that had previously dominated this event. In 1998, Fritz 5 was released including a Friend mode which would cause the engine to adjust its strength of play over the course of a game based on the level the opponent appeared to be playing. Fritz 5.32 was released soon after replacing the 16-bit architecture with a 32-bit one. In 2002, Deep Fritz drew the Brains in Bahrain match against Vladimir Kramnik 4–4. Fritz 7, which was released that year, included the ability to play on the Playchess server. In November 2003, X3D Fritz, a version of Deep Fritz with a 3D interface, drew a four-game match against Garry Kasparov. Fritz 8, which appeared around this time, provided a 3D Spanish room setting for games to take place. Fritz 9 added a 3D virtual opponent, the Turk. In 2004, Fritz 8 added a Handicap and Fun mode, allowing players to choose the Elo rating and style that the engine will use. Chessbase native engines can use the Handicap feature: Chess Tiger, Crafty, the Fritz engine, Hiarcs, Houdini, Junior, Rybka, Shredder and Zappa. Some UCI engines can also make use of Handicap, eg. Fruit and Stockfish. On June 23, 2005, in the ABC Times Square studios, the AI Accoona Toolbar, driven by a Fritz 9 prototype, drew against the then FIDE World Champion Rustam Kasimdzhanov. From November 25 to December 5, 2006 Deep Fritz played a six-game match against Kramnik in Bonn. Fritz