The
C shell (
csh or the improved version,
tcsh, on most machines) is a
Unix shell that was created by
Bill Joy while he was a graduate student at
University of California, Berkeley in the late 1970s. It has been distributed widely, beginning with the 2BSD release of the
BSD Unix system that Joy began distributing in 1978. Other early contributors to the ideas or the code were Michael Ubell,
Eric Allman, Mike O'Brien and Jim Kulp.