Prolog is the programming language created by Alain Colmerauer and Philippe Roussel in 1972 for logic programming.
The name Prolog is derived from “programmation en logique,” or “programming in logic.” Colmerauer developed the language in Marseille with Roussel, initially to support experiments involving natural-language processing.
Instead of describing a sequence of commands in the usual way, a Prolog program states facts and rules. The system then searches for solutions to queries by using unification and backtracking.
Prolog became especially influential in artificial intelligence, expert systems, and computational linguistics. It is sometimes confused with Datalog, a related logic-programming language, but Prolog supports a broader programming model and commonly permits recursive rules and compound terms.