Prolog

Prolog
ParadigmLogic
Designed byAlain Colmerauer
First appeared1972 (1972)
Stable release
Part 1: General core-Edition 1 (June 1995 (1995-06))
Part 2: Modules-Edition 1 (June 2000 (2000-06))
Part 3: Definite clause grammar rules (June 2025 (2025-06))
Typing disciplineUntyped (its single data type is "term")
Filename extensions.pl, .pro, .P
WebsitePart 1: www.iso.org/standard/21413.html
Part 2: www.iso.org/standard/20775.html
Part 3: www.iso.org/standard/83635.html
Major implementations
Amzi! Prolog, B-Prolog, Ciao, ECLiPSe, GNU Prolog, LPA Prolog, Poplog, P#, Quintus Prolog, Scryer Prolog, SICStus, Strawberry, SWI-Prolog, Tau Prolog, tuProlog, WIN-PROLOG XSB, YAP.
Dialects
ISO Prolog, Edinburgh Prolog
Influenced by
Planner
Influenced
CHR, Clojure, Datalog, Erlang, Epilog, KL0, KL1, Logtalk, Mercury, Oz, Strand, Visual Prolog

Prolog is a logic programming language that has its origins in artificial intelligence, automated theorem proving, and computational linguistics.

Prolog has its roots in first-order logic, a formal logic. Unlike many other programming languages, Prolog is intended primarily as a declarative programming language: the program is a set of facts and rules, which define relations. A computation is initiated by running a query over the program.

Prolog was one of the first logic programming languages and remains the most popular such language today, with several free and commercial implementations available. The language has been used for theorem proving, expert systems, term rewriting, type systems, and automated planning, as well as its original intended field of use, natural language processing.

Prolog is a Turing-complete, general-purpose programming language, which is well-suited for intelligent knowledge-processing applications.