Song

A song is a relatively short musical composition. All songs contain vocal parts that are accompanied with the human voice, commonly accompanied by other musical instruments (exceptions would be scat songs) and feature words (lyrics). It is typically for a solo singer, though may also be a duet, trio, or more voices (works with more than one voice to a part, however, are considered choral). The words of songs are typically of a poetic, rhyming nature, although they may be religious verses or free prose. Songs can be broadly divided into many different forms, depending on the criteria used. One division is between "art songs", "popular music songs", and "folk songs". Other common methods of classification are by purpose (sacred vs secular), by style (dance, ballad, Lieder, etc.) or by time of origin (Renaissance, Contemporary, etc).

Colloquially, song is often used to refer any music composition, even those without vocals (though in music styles that are predominantly vocal-based, a composition without vocals is often called an instrumental). In European classical music, however, this usage is considered incorrect and "song" should only be used to describe a composition for the human vocals.