[7] Alongside the Macintosh, Amiga, Apple IIGS and Acorn Archimedes, the ST is part of a mid-1980s generation of computers with 16 or 16/32-bit processors, 256 KB or more of RAM, and mouse-controlled graphical user interfaces.

In the early 1990s, Atari released three final evolutions of the ST with significant technical differences from the original models: TT030 (1990), Mega STE (1991), and Falcon (1992).

Atari discontinued the entire ST computer line in 1993, shifting the company's focus to the Jaguar video game console.

When his idea was rejected, he left Atari to form a small think tank called Hi-Toro in 1982 and began designing the new "Lorraine" chipset.

After leaving Commodore International in January 1984, Jack Tramiel formed Tramel (without an "i") Technology, Ltd. with his sons and other ex-Commodore employees and, in April, began planning a new computer.

He secured funding and bought Atari's consumer division, which included the console and home computer departments, in July.

[7][11] The lead architect of the new computer project at Tramel Technology and Atari Corporation was ex-Commodore employee Shiraz Shivji, who previously worked on the Commodore 64's development.

The chip needed more time to complete, so AMY was dropped in favor of a commodity Yamaha YM2149F variant of the General Instrument AY-3-8910.

Digital Research was also in the process of building GEMDOS, a disk operating system for GEM, and debated whether a port of it could be completed in time for product delivery in June.

This gave the ST a fast, hierarchical file system, essential for hard drives, and provided programmers with function calls similar to MS-DOS.

After six months of intensive effort following Tramiel's takeover, Atari announced the 520ST at the Winter Consumer Electronics Show in Las Vegas in January 1985.

[21] But Jack Tramiel admitted that sales of its earlier 8-bit systems were "very, very slow",[2] Atari was out of cash, and employees feared that he would shut the company down.

[20] John C. Dvorak wrote that the public saw both Commodore and Atari as selling "cheap disposable" game machines,[32] in part because of their computers' sophisticated graphics.

It is an all-in-one unit, similar to earlier home computers like the Commodore 64, but with a larger keyboard with cursor keys and a numeric keypad.

Some commercial software, particularly games, shipped by default on single-sided disks, even supplying two 360 KB floppies instead of a single double-sided one, to avoid alienating early adopters.

Atari upgraded the basic design in 1986 with the 1040STF, stylized as 1040STF: essentially a 520ST with twice the RAM and with the power supply and a double-sided floppy drive with twice the capacity, and built-in instead of external.

[40] A limited number of 1040STFs shipped with a single-sided floppy drive of 360KB storage capacity verses 720KB in the double sided version.

Renamed to Mega, it includes a high-quality detached keyboard, a stronger case to support the weight of a monitor, and an internal bus expansion connector.

In late 1989, Atari Corporation released the 520STE and 1040STE (also written STE), enhanced version of the ST with improvements to the multimedia hardware and operating system.

It features an increased color palette of 4,096 colors from the ST's 512 (though the maximum displayable palette without programming tricks is still limited to 16 in the lowest 320 × 200 resolution, and even fewer in higher resolutions), genlock support, and a blitter coprocessor (stylized as "BLiTTER") which can quickly move large blocks of data (particularly, graphics data) around in RAM.

[47][48] That year, WordPerfect threatened to discontinue the Atari ST version of its word processor because the company discovered that pirate bulletin board systems (BBSs) were distributing it, causing ST-Log to warn that "we had better put a stop to piracy now ... it can have harmful effects on the longevity and health of your computer".

Graphical touchscreen point of sale software for restaurants was originally developed for Atari ST by Gene Mosher under the ViewTouch[56] copyright and trademark.

The ST had success in gaming due to the low cost, fast performance, and colorful graphics compared to contemporary PCs or 8-bit systems.

ST game developers include Peter Molyneux, Doug Bell, Jeff Minter, Éric Chahi, Jez San, and David Braben.

The realtime pseudo-3D role-playing video game Dungeon Master, was developed and released first on the ST, and is considered to be the best-selling software ever produced for the platform.

Combined with sound hardware that was not considered the equal of the Amiga or Commodore 64, the machine's performance for 2D arcade games was seen as its weakest point.

The ST's low cost, built-in MIDI ports, and fast, low-latency response times made it a favorite with musicians.

In 1986, most production models became STFs, with an integrated single- (520STF) or double-sided (1040STF) double density floppy disk drive built-in, but no other changes.

As originally released in the 520STE/1040STE: The members of the ST family are listed below, in roughly chronological order: The 130ST was intended to be a 128 KB variant.

Atari did produce a quantity of 4160STE metallic case badges which found their way to dealers, so it's not uncommon to find one attached to systems which were originally 520/1040STE.