Manufacturer: Atari
Launches: 1985
CPU: Motorola 68000 @ 8MHz
Memory: 512 KB ~ 4 MB
Support: Diskette 3½" DD
Hard drive:
Operating system: TOS
Innovations: It was the first computer to include a color graphical interface (Digital Research's GEM), and its high resolution in monochrome mode made it ideal for desktop publishing and CAD.
It also included a MIDI interface, making it a common device in music studios.
It was also the first series of personal computers to include up to one megabyte of RAM from the factory.

The ST family (which stands for Sixteen/Thirty-two, referring to the internal and external bus of the Motorola 68000 processor it included) is the successor to the Atari 8-bit family.
It rivaled the Commodore Amiga and the Apple Macintosh, for which it was a cheaper alternative.

It included the 260, 520, 1040, and Mega models, which were released between 1985 and 1991.

Manufacturer: Atari
Launches: 1989
CPU: Motorola 68000
Memory: 512 KB ~ 4 MB
Support: Diskette 3½" DD
Hard drive: None
Operating system: TOS 1.06

In late 1989, Atari Corporation released the 520STE and 1040STE, an improved version of the ST with improvements in multimedia hardware and the operating system.

Manufacturer: Atari
Launches: 1990
CPU: Motorola 68030 @ 32MHz
Memory: 2 MB ~ 16 MB
Support:
Hard drive: 50 MB
Operating system: TOS 3.01