Codetta

Coda [ˈkoːda] (Italian for "tail", plural code) is a term used in music primarily to designate a passage that brings a piece (or a movement) to an end. Technically, it is an expanded cadence. It may be as simple as a few measures, or as complex as an entire section.

The presence of a coda as a structural element in a movement is especially clear in works written in particular musical forms. Codas were commonly used in both sonata form and variation movements during the Classical era. In a sonata form movement, the recapitulation section will, in general, follow the exposition in its thematic content, while adhering to the home key. The recapitulation often ends with a passage that sounds like a termination, paralleling the music that ended the exposition; thus, any music coming after this termination will be perceived as extra material, i.e., as a coda. In works in variation form, the coda occurs following the last variation and will be very noticeable as the first music not based on the theme.

One of the ways that Beethoven extended and intensified Classical practice was to expand the coda sections, producing a final section sometimes of equal musical weight to the foregoing exposition, development, and recapitulation sections and completing the musical argument. For one famous example, see Symphony No. 8 (Beethoven).

Charles Burkhart suggests that the reason codas are common, even necessary, is that, in the climax of the main body of a piece, a "particularly effortful passage", often an expanded phrase, is often created by "working an idea through to its structural conclusions" and that, after all this momentum is created, a coda is required to "look back" on the main body, allow listeners to "take it all in", and "create a sense of balance."

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