Lisp is a family of programming languages designed by John McCarthy in 1958. In a famous article, he shows that it is possible to use exclusively mathematical functions as elementary data structures (which is possible once there is a formal mechanism for manipulating functions: Alonzo Church's Lambda Calculus).

The Lisp language was designed primarily for processing symbolic data. It is a formal mathematical language. During the 1970s and 1980s, Lisp became the main language of the artificial intelligence community, pioneering applications such as automatic storage management, interpreted languages and functional programming.

Its name comes from LIst Processing (the list is the fundamental data structure of this language). Both the data and the program are represented as lists, which allows the language to manipulate the source code like any other type of data.

There are several dialects of Lisp, the best known being Common Lisp and Scheme.