• Uses a new method to save revision and data in a space efficient way.
• Changes do not destroy the original.
• Revisions can be retrieved according to ranges of revision numbers, symbolic names, dates, authors, and states.
• One user restriction for modification. However, RCS allows read access when two individuals request same file. Can notify the individuals of who is working on a resource.
• Control releases and configurations. Revisions can be assigned symbolic names and marked as released, stable, experimental, etc. With these facilities, configurations of modules can be described simply and directly.
• RCS needs little extra space for the revisions (only the differences). If intermediate revisions are deleted, the corresponding changes are compresse accordingly.

Basic commands:

• ci filename: Check in a file, filename, under RCS.
• co -l filename: Check out a file, filename, for editing
• co filename: Check out a file, filename, for read-only access
• rcsdiff filename: Show differences between a file, filename, and its reference copy.
• rcs -l filename: Lock changes to a file (if checked out) or lock the file so only you can check it out (if it is not already checked out).