The Atari ST is a line of home computers from Atari Corporation and the successor to the Atari 8-bit family. The initial ST model, the 520ST, saw limited release in April-June 1985 and was widely available in July. The Atari ST is the first personal computer to come with a bitmapped color GUI, using a version of Digital Research’s GEM released in February 1985. The 1040ST, released in 1986, is the first personal computer to ship with a megabyte of RAM in the base configuration and also the first with a cost-per-kilobyte of less than US$1.

The Atari ST is part of a mid-1980s generation of home computers that have 16 or 32-bit processors, 256 KiB or more of RAM, and mouse-controlled graphical user interfaces. This generation includes the Macintosh, Commodore Amiga, Apple IIGS, and, in certain markets, the Acorn Archimedes. “ST” officially stands for “Sixteen/Thirty-two”, which refers to the Motorola 68000’s 16-bit external bus and 32-bit internals.

The ST was sold with either Atari’s color monitor or the less expensive monochrome monitor. The system’s two color graphics modes are only available on the former while the highest resolution mode needs the monochrome monitor.

In some markets, particularly Germany, the machine gained a strong foothold as a small business machine for CAD and desktop publishing work. Thanks to its built-in MIDI ports, the ST enjoyed success for running music-sequencer software and as a controller of musical instruments among both amateurs and well-known musicians.

The ST was superseded by the Atari STE, Atari TT, Atari MEGA STE, and Falcon computers.

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