CLIPS is an acronym for the C language integrated production system. The syntax and name was inspired by Charles Forgy's OPS (official production system, although there was nothing really official about it). The first versions of CLIPS were developed starting in the mid 1980s at NASA-Johnson Space Center until the early 1990s when funding ceased because of Federal Budget problems, and a mandate for NASA to buy commercial software off-the-shelf rather than develop it.

CLIPS is probably the most widely used expert system tool because it is fast, efficient and free. Descendants of the CLIPS language include Jess, Eclipse, FuzzyCLIPS and others. A college textbook, Expert System Principles and Practice is available about CLIPS, as well as a book on Jess. Jess the rule-based portion of CLIPS written in Java. CLIPS also incorporates a complete object-oriented language for writing expert systems. Because CLIPS is written now in C++ it has full multiple inheritance, which languages such as Java and C# lack.