Tape Operating System

(TOS) An IBM operating system for System 360, used in the early days around 1965 to support the IBM 360 model 30 et al. TOS was a predecessor to IBM's Disk Operating System.

TOS died out really early as disks such as the 2311 and 2314 became common with the IBM 360 whereas thet had been a real luxury on the IBM 7090.

[Relationship to BOS?]