Atari ST is a home computer hosted by the Atari Company at the Las Vegas Consumer Electronics Fair in 1985 and released mid-year. The letters "ST " is the abbreviation of "Sixteen/thirty-two " (in Castilian, sixteen/thirty-two), reference of the 32-bit internal processor of Motorola 68000 with 16-bit external buses.
It was the fair's big surprise, as it was only six months since Jack Honey, Commodore's founder, had bought Atari. The ST series was released to the market by Atari although in his stay at Commodore, he had hired Amiga Corp. To build a 16-bit personal computer, but the legal issues on Commodore's departure caused the dissolution of that contract.
As a result Commodore computer launched the Amiga and Atari created the ST using custom electronics to launch a computer coinciding with the release of Commodore's friend.
It was also designed to be a "Macintosh killer ", and was called the "Jackintosh " as they were a serious alternative to Macs (in the Music field and desktop publishing) for much less money. In fact, Atari launched this series under the slogan "Power without the price ".
It offered features never before found on personal computers: 16-bit microprocessor, multiple ports, serial MIDI interface, high graphical resolution, number of colors, enhanced GUI (graphical user interface). It was much cheaper and expandable than the Macintosh (MIDI, graphics, colors, etc) and the competitors were not very numerous (the Commodore 128, PC AT, and compatible, and the old CP/M). This explains why more than 6 million of Atari ST were sold worldwide