Prolog is a logic programming language which is widely used in Artificial Intelligence applications especially in Expert Systems.
The name Prolog was chosen by Philippe Roussel as an abbreviation for "PROgrammation en LOGique” (French for programming in logic). It was created around 1972 by Alain Colmerauer with Philippe Roussel
Prolog primarily uses the representations that we learnt in Predicate Calculus.
John ate an Apple would be represented in the calculus as
Ate (John, Apple)
Similarly in Prolog,
Patient has symptom of Fever would be coded as
Symptom (Patient, Fever)