Microchess

Microchess
A chess game being played on a board, next to a circuit board with several buttons as inputs connected to a cassette player
Microchess on a KIM-1 microcomputer
Developer(s)Peter R. Jennings
Publisher(s)Micro-Ware / Personal Software
Platform(s)KIM-1, Altair 8800, Apple II, Atari 8-bit, PET, TRS-80, TRS-80 Color Computer
ReleaseDecember 18, 1976
Genre(s)Computer chess

Microchess, sometimes written as MicroChess, is a chess program developed for the MOS Technology KIM-1 microcomputer by Peter R. Jennings in 1976, and published by his company Micro-Ware. The game plays chess against the human player at a beginner level, with the player entering moves via a keyboard and the computer responding, both in a custom chess notation. The game was ported to many other microcomputers such as the TRS-80, Apple II, Commodore PET, and Atari 8-bit computers by Micro-Ware and its successor company Personal Software (later VisiCorp) between 1976 and 1980, with later versions featuring graphics and more levels of play. A dedicated hardware version of the game called ChessMate was produced by Commodore International in 1978, and the game's engine was licensed to Novag for its dedicated Chess Champion Mk II chess computer in 1979.

The game was created by Jennings over the course of around six months in 1976. He developed it with the aim of making a product that could be widely sold, rather than as the most advanced chess engine possible. It was possibly the first computer game to be sold commercially, and was the first commercial chess program for microcomputers and the first software package to sell 50,000 copies. Micro-Ware itself was possibly the first software publishing company. Microchess ultimately sold over a million copies across all of its versions by the mid-1980s, and variants were sold into the early 1990s. Despite being commercially successful, it has been largely regarded by critics as a poor chess game.