Source code file written in Lisp, a programming language that has several different dialects including Common Lisp and Scheme; contains plain text program code that is run with a Lisp interpreter; may be an entire program or a part of a larger Lisp application.

LISP files can be edited with any text editor. However, they are more easily viewed and edited using an editor that supports Lisp syntax highlighting. NOTE: Lisp has been widely used in the areas of artificial intelligence (AI), natural language processing (NLP), and symbolic processing.