Chart (music)

In its broadest sense, the head of a piece of music is its main theme, particularly in jazz, where the term takes on a more specific set of connotations. In other types of music, "head" may refer to the first or most prominent section of a song. The term may, though obtusely, be applied to classical music, insofar as classical pieces generally bear similar thematic elements, but the preferred term in this instance is (main) theme or subject. The term "head" is most often used in jazz and may refer to the thematic melody, an instance of it in a performance of the song, or a more abstract compilation of ideas as to what the song is. It may also, though uncommonly, refer to the first section of the melody, or the theme riff in the melody.

There is a slightly related musical direction, D.C. or da capo (Italian, from head), which means to go back to the very beginning of the sheet music and play to the end, typically ignoring all repeat signs.

The idea a head represents comprises a combination of elements. No one piece of written music defines what the "head" of many jazz tunes really is, but a boiler-plate jazz chart, which is often only a page long in large print, will tell you:

as well as more general information such as

The form is an even more general and abstract concept dealing with the theoretical context in which the actual music is being played: the chord progression, its sections and other miscellaneous events such as kicks or time changes are all important information that the performers must keep track of. Two important standard forms over which hundreds of heads have been written are the 12-bar blues and rhythm changes. Some heads are based on the forms of other tunes, such as Charlie Parker's "Ornithology", which is based on Morgan Lewis's "How High the Moon".

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