(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.