IBM's first family of computer systems introduced in 1964. It was the first time in history that a complete line of computers was announced at one time. Although considerable enhancements have been made, much of the 360 architecture is still carried over in current-day IBM mainframes. Since its inception, trillions of dollars worth of information systems have been developed for this platform.

The 360, which took four years to develop and cost $5 billion ($24 billion today) was an enormous and risky undertaking. Thomas Watson, Jr. literally "bet his company" on the project. The 360 has been ranked as one of the major business accomplishments in American history alongside of Ford's Model T and Boeing's 707. See IBM mainframes.