system> (CTss) One of the earliest (1963) experiments in the design of interactive time-sharingoperating systems. CTss was ancestral to Multics, Unix, and ITs. It was developed at the MIT Computation Center by a team led by Fernando J. Corbato. CTss ran on a modified IBM 7094 with a second 32K-word bank of memory, using two 2301 drums for swapping. Remote access was provided to up to 30 users via an IBM 7750communications controller connected to dial-upmodems. The name ITs (Incompatible time-sharingsystem) was a hack on CTss, meant both as a joke and to expresssome basic differences in philosophy about the way I/O servicesshould be presented to user programs. (1997-01-29)