rc

1. (run commands) The {filename

extension} common to many {Unix} configuration files, e.g.

{.newsrc}, {.cshrc}, {.twmrc}, elmrc, etc.

The suffix "rc" derives from a script-creation utility in

{CTSS} called "{runcom}" (for "run commands").

{Unix FAQ

(http://www.cis.ohio-state.edu/hypertext/faq/usenet/unix-faq/faq/top.ht