In music

Music

Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...

, a song is a composition

Musical composition

Musical composition can refer to an original piece of music, the structure of a musical piece, or the process of creating a new piece of music. People who practice composition are called composers.- Musical compositions :...

 for voice

Human voice

The human voice consists of sound made by a human being using the vocal folds for talking, singing, laughing, crying, screaming, etc. Its frequency ranges from about 60 to 7000 Hz. The human voice is specifically that part of human sound production in which the vocal folds are the primary...

 or voices, performed by singing

Singing

Singing is the act of producing musical sounds with the voice, and augments regular speech by the use of both tonality and rhythm. One who sings is called a singer or vocalist. Singers perform music known as songs that can be sung either with or without accompaniment by musical instruments...

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A song may be accompanied by musical instrument

Musical instrument

A musical instrument is a device created or adapted for the purpose of making musical sounds. In principle, any object that produces sound can serve as a musical instrument—it is through purpose that the object becomes a musical instrument. The history of musical instruments dates back to the...

s, or it may be unaccompanied, as in the case of a cappella

A cappella

A cappella music is specifically solo or group singing without instrumental sound, or a piece intended to be performed in this way. It is the opposite of cantata, which is accompanied singing. A cappella was originally intended to differentiate between Renaissance polyphony and Baroque concertato...

 songs. The lyrics (words) of songs are typically of a poetic

Poetry

Poetry is a form of literary art in which language is used for its aesthetic and evocative qualities in addition to, or in lieu of, its apparent meaning...

, rhyming

Rhyme

A rhyme is a repetition of similar sounds in two or more words and is most often used in poetry and songs. The word "rhyme" may also refer to a short poem, such as a rhyming couplet or other brief rhyming poem such as nursery rhymes.-Etymology:...

 nature, though they may be religious verses or free prose

Prose

Prose is the most typical form of written language, applying ordinary grammatical structure and natural flow of speech rather than rhythmic structure...

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A song may be for a solo singer, a duet, trio

Trio (music)

Trio is generally used in any of the following ways:* A group of three musicians playing the same or different musical instrument.* The performance of a piece of music by three people.* The contrasting section of a piece in ternary form...

, or larger ensemble involving more voices

Part song

A part song is a form of choral music which consists of a secular song which has been written or arranged for several vocal parts, commonly SATB choir, but also for an all-male or all-female ensemble...

. Songs with more than one voice to a part are considered choral

Choir

A choir, chorale or chorus is a musical ensemble of singers. Choral music, in turn, is the music written specifically for such an ensemble to perform.A body of singers who perform together as a group is called a choir or chorus...

 works.