Prolog
Overview
Logic programming
Logic programming is, in its broadest sense, the use of mathematical logic for computer programming. In this view of logic programming, which can be traced at least as far back as John McCarthy's [1958] advice-taker proposal, logic is used as a purely declarative representation language, and a...
language associated with artificial intelligence
Artificial intelligence
Artificial intelligence is the intelligence of machines and the branch of computer science that aims to create it. AI textbooks define the field as "the study and design of intelligent agents" where an intelligent agent is a system that perceives its environment and takes actions that maximize its...
and computational linguistics
Computational linguistics
Computational linguistics is an interdisciplinary field dealing with the statistical or rule-based modeling of natural language from a computational perspective....
.
Prolog has its roots in first-order logic
First-order logic
First-order logic is a formal logical system used in mathematics, philosophy, linguistics, and computer science. It goes by many names, including: first-order predicate calculus, the lower predicate calculus, quantification theory, and predicate logic...
, a formal logic
Formal logic
Classical or traditional system of determining the validity or invalidity of a conclusion deduced from two or more statements...
, and unlike many other programming language
Programming language
A programming language is an artificial language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine and/or to express algorithms precisely....
s, Prolog is declarative
Declarative programming
In computer science, declarative programming is a programming paradigm that expresses the logic of a computation without describing its control flow. Many languages applying this style attempt to minimize or eliminate side effects by describing what the program should accomplish, rather than...
: the program logic is expressed in terms of relations, represented as facts and rules. A computation is initiated by running a query over these relations.
The language was first conceived by a group around Alain Colmerauer
Alain Colmerauer
Alain Colmerauer is a French computer scientist.After completing his Ph.D. at the University of Grenoble, he spent 1967–1970 as Assistant Professor at the University of Montreal, where he created Q-Systems, one of the earliest linguistic formalisms used in the development of the TAUM-METEO machine...
in Marseille
Marseille
Marseille , known in antiquity as Massalia , is the second largest city in France, after Paris, with a population of 852,395 within its administrative limits on a land area of . The urban area of Marseille extends beyond the city limits with a population of over 1,420,000 on an area of...
, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, in the early 1970s and the first Prolog system was developed in 1972 by Colmerauer with Philippe Roussel.
Prolog was one of the first logic programming languages, and remains among the most popular such languages today, with many free and commercial implementations available.
