Written by Marty Hirsch, an expert [IBM-PC](IBM_PC "IBM PC") programmer previously known for a program called [AI-Chess](AI_Chess "AI Chess"), M-Chess is a new program that has taken 3 man-years to develop. By means of logical switches in the [evaluator](Evaluation "Evaluation"), the program dynamically selects a set of heuristics depending on the [type of position](Game_Phases "Game Phases") (early [opening](Opening "Opening"), late opening, early [middle game](Middlegame "Middlegame"), late middle game, [endgame](Endgame "Endgame"), several specific endgames). [Development](Development "Development") is stressed in the opening, [king safety](King_Safety "King Safety") and [mobility](Mobility "Mobility") in the middle game, and [passed pawns](Passed_Pawn "Passed Pawn") and an [active king](King_Centralization "King Centralization") in the endgame. A [small hash table](Pawn_Hash_Table "Pawn Hash Table") is used for [pawn-structure](Pawn_Structure "Pawn Structure") evaluation. Positional evaluation can exceed the value of a pawn. The [search](Search "Search") techniques include [check extensions](Check_Extensions "Check Extensions") and [capture extensions](Capture_Extensions "Capture Extensions"), but no [singular extensions](Singular_Extensions "Singular Extensions"). The [main hash table](Transposition_Table "Transposition Table") is only used during the full-width portion of the search and does not record the [best move](Best_Move "Best Move") from previous [iterations](Iterative_Deepening "Iterative Deepening"). [Move ordering](Move_Ordering "Move Ordering") is obtained from the [principal variation](Principal_Variation "Principal Variation") and a modified [history heuristic](History_Heuristic "History Heuristic"). 

M-Chess Professional is a chess program for PCs by Martin Hirsch. It won the title of [ICCA's](ICCA "ICCA") World Personal Computer Chess Champion [1991/92](WMCCC_1991 "WMCCC 1991"). Previous versions of M-Chess achieved a numerous honours including best computer at [Aegon 1991](Aegon_1991 "Aegon 1991"), second place in the [ACM tournament in 1991](ACM_1991 "ACM 1991") and first place in the [Uniform Platform Computer Chess Championship in 1992](UPCCC_1992 "UPCCC 1992"). M-Chess Professional has an unusual design that attempts to emulate the style of a strong human player by using complex [pattern recognition](Pattern_Recognition "Pattern Recognition"), emphasizing positional aspects and having precise knowledge of a number of endgames, while being tactically powerful. M-Chess Professional is commercially available with a excellent [interface](GUI "GUI") and an extensive set of features. It is currently ranked second in the [Swedish Computer Rating List](SSDF "SSDF") . 

This is the latest version of MChess Professional which has many computer chess achievements including First Place in the 1995 World Microcomputer Championship and beating three grandmasters in one event at Aegon, 1995. This program uses comprehensive evaluations, and unique algorithms to detect long-range tactics. It has a dynamic playing style and is known for its exciting play and excellent results against strong human opponents.