Lisp is a family of programming languages that has a long history and a distinctive, fully parenthesized prefix notation). Lisp was originally created as a practical mathematical notation for computer programs, influenced by the notation of Alonzo Churchs lambda calculus. It quickly became a favored programming language for artificial intelligence (AI) research). Lisp is a functional programming language that was designed for easy manipulation of data strings. In Lisp, all computation is expressed as a function of at least one object, and Lisps ability to compute with symbolic expressions rather than numbers makes it convenient for AI applications. Lisp supports all kinds of data types like objects, structures, lists, vectors, adjustable arrays, set, trees, hash-tables, and symbols. Lisp is still used for AI programming as well as several other functions. Lisp is the second-oldest high-level programming language still in common use, after Fortran).

It is important to note that "lisp" can also refer to a speech impediment that specifically relates to making the sounds associated with the letters S and Z.