System/360: A Retrospective View

In the current article, adapted from a lecture he gave at the Computer Museum on November 10, 1983, Evans summarizes the events, organizations, product lines, and motivations that led to the System/360, IBM's major shift to compatible processors, peripherals, and software for both business and scientific applications. A version of this article was published in the Computer Museum Report (Number 9, Summer 1984). Some of this IBM history has been detailed in the Annals previously; see special issues on the 701 (Vol. 5, No. 2) and 650 (Vol. 8, No. 1) and articles by Bashe, Hurd, McPherson et al., Phelps, etc.; also see the recent volume by Bashe et al., IBM's Early ' Computers (MIT Press, 1985). We are pleased to have the author's personal view of the principles involved in the System/360, the environment during its development, some of the problems encountered, and the consequences of the 360, both for IBM and for the information processing industry.