 Instead of using branches, many teams just use the built-in locking mechanism and work on a single "head" branch.RCS revolves around the usage of "revision groups" or sets of files that have been checked-in via the "co" (checkout) and "ci" (check-in) commands.By default, a checked-in file is removed and replaced with a ",v" file (so foo.rb when checked in becomes foo.rb,v) which can then be checked out by anyone with access to the revision group.