A network-transparent program that allows Web developers to keep track of different development versions of source code. CVS does not maintain multiple versions of source code files but keeps a single copy and records of all of the changes that are made. When a developer wants a particular development version of a file, CVS will reconstruct that version based on its records.
CVS was created in the Unix operating system environment and is available in both Free Software Foundation and commercial versions. It is a popular tool for programmers working on Linux and other Unix-based systems. CVS uses another program, Revision Control System (RCS), to do the actual revision management - that is, keeping the record of changes that goes with each source code file. The writers of the CVS FAQs are careful to emphasize that CVS is not a build system, a code configuration management system, or a substitute for other good development practices, but simply a way to control the versions of the pieces of a program as they are developed. It was developed by Dick Grune in the 1980s and has become popular in the open source software world. It is released under the GNU General Public License.