Introduction to VC VC Concepts
VC currently works with three different version control systems or ``back ends'': RCS, CVS, and SCCS.
RCS is a free version control system that is available from the Free Software Foundation. It is perhaps the most mature of the supported back ends, and the VC commands are conceptually closest to RCS. Almost everything you can do with RCS can be done through VC.
CVS is built on top of RCS, and extends the features of RCS, allowing for more sophisticated release management, and concurrent multi-user development. VC supports basic editing operations under CVS, but for some less common tasks you still need to call CVS from the command line. Note also that before using CVS you must set up a repository, which is a subject too complex to treat here.
SCCS is a proprietary but widely used version control system. In terms of capabilities, it is the weakest of the three that VC supports. VC compensates for certain features missing in SCCS (snapshots, for example) by implementing them itself, but some other VC features, such as multiple branches, are not available with SCCS. You should use SCCS only if for some reason you cannot use RCS.Introduction to VC VC Concepts