A soap opera (also called a daytime drama or soap) is a genre of a long-running radio or television serial, frequently characterized by melodrama, ensemble casts, and sentimentality. The term soap opera originated from radio dramas' original sponsorship by soap manufacturers. The term was preceded by horse opera, a derogatory term for low-budget Westerns. Some authorities exclude short-running serial dramas from their definition.
BBC Radio's The Archers, first broadcast in 1950, is the world's longest-running soap opera. The longest-running television soap opera is Coronation Street, which was first broadcast on ITV in 1960.