Song structure

Song structure or the musical forms of songs in traditional music and music are typically sectional, repeating forms used in songs, such as strophic form and is a part of the songwriting process. Other common forms include thirty-two-bar form, verse-chorus form, and the twelve-bar blues. Popular music songs traditionally use the same music for each verse of stanza of lyrics (as opposed to songs that are "through-composed", an approach used in classical music art songs). Pop and traditional forms can be used even with songs that have structural differences in melodies. The most common format is introduction (intro), verse, pre-chorus, chorus (or refrain), verse, pre-chorus, chorus, bridge ("middle eight"), verse, chorus and outro. In rock music styles, notably heavy metal music, there is usually a guitar solo in the song. In pop music, there may be a guitar solo, or the solo may be performed by a synthesizer player or sax player.

The formal sections found in songs are the verse, chorus, bridge, hook, and refrain: "All songs are put together with some or all of these parts in a particular pattern." The foundation of popular music is the "verse" and "chorus" structure. "Pop and rock songs nearly always have both a verse and a chorus. The primary difference between the two is that when the music of the verse returns, it is almost always given a new set of lyrics, whereas the chorus usually retains the same set of lyrics every time its music appears." Both are essential elements, with the verse usually played first. Exceptions abound, with "She Loves You" by The Beatles being an early example in the rock music genre. Each verse usually employs the same melody (possibly with some slight modifications), while the lyrics usually change for each verse. The chorus (or "refrain") usually consists of a melodic and lyrical phrase which is repeated. Pop songs may have an introduction and coda ("tag"), but these elements are not essential to the identity of most songs. Pop songs often connect the verse and chorus via a bridge, which as its name suggests, is a section which connects the verse and chorus at one or more points in the song.

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