So I'm adding a few systems together here. From Wikipedia:
The Atari 8-bit family is a series of 8-bit home computers introduced by Atari, Inc. in 1979 with the Atari 400 and Atari 800. As the first home computer architecture with coprocessors, it has graphics and sound more advanced than most of its contemporaries. Video games were a major appeal, and first-person space combat simulator Star Raiders is considered the platform's killer app. The "Atari 8-bit family" label was not contemporaneous. Atari, Inc., used the term "Atari 800 [or 400] home computer system", often combining the model names into "Atari 400/800" or "Atari home computers".