Books in this subject area deal with the Lisp family of computer programming languages with a long history and a distinctive, fully parenthesized syntax. Lisp is the second-oldest high-level programming language in widespread use today; only Fortran is older. Lisp was originally created as a practical mathematical notation for computer programs. It quickly became the favored programming language for artificial intelligence (AI) research. As one of the earliest programming languages, Lisp pioneered many ideas in computer science, including tree data structures, automatic storage management, dynamic typing, object-oriented programming, and the self-hosting compiler.