What is Song ?

A song is a musical composition. Songs contain vocal parts that are performed, 'sung,' and feature words (lyrics), commonly accompanied by musical instruments (exceptions would be a cappella songs). The words of songs are typically of a poetic, rhyming nature, although they may be religious verses or free prose. The words are the lyrics.

Songs are typically for a solo singer, though there may also be a duet, trio, or more voices (works with more than one voice to a part, however, are considered choral). 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).