Abbrev. for source code control system. A utility program, now obsolete, developed initially to run under UNIX, that kept track of a set of versions and variants of a text file (usually source language). Sccs could retrieve any one of the set of versions and variants it held, and could receive new versions or variants together with a commentary concerning who made the change and what had changed from the previous version or variant. An important feature of sccs was that it did not keep the full source text of each version or variant. Instead it kept one full text and a set of differences between that version and all the other versions and variants. Hence sccs provided a more economical means of storing a module with many versions and variants than, for example, storing them all in separate files. Sccs's principles have influenced all subsequent version control systems.