Compatible Timesharing System
<operating system> (CTSS) One of the earliest (1963) experiments in the design of interactive
time-sharing operating 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 7750 {communications controller} connected to dial-up modems.
The name
ITS (Incompatible
time-sharing System) was a hack on CTSS, meant both as a joke and to express some basic differences in philosophy about the way I/O services should be presented to user programs
