How to RCS ? - - - - - - - - First time init mkdir RCS Check in ci -u FILE Check out (lock) co -l FILE Five minute O'Reilly tutorial https://web.archive.org/web/20150622185358/http://archive.oreilly.com/pub/a/perl/excerpts/system-admin-with-perl/five-minute-rcs-tutorial.html See also • RCS → CVS → Mercurial → Subversion → GIT + tig → Fossil • https://en.wikipedia.org/wiki/Comparison_of_version-control_software • https://en.wikipedia.org/wiki/Versioning_file_system