The phrase theme music usually refers to that of a radio program, television program, or movie. It is a piece that is written specifically for that show and usually played during the title sequence and/or end credits. If it is accompanied by lyrics, most often associated with the show, it is a theme song.
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Theme (music)
In music, a theme is the initial or primary melody. The 1958 Encyclopédie Fasquelle defines a theme as follows:"Any element, motif, or small musical piece that has given rise to some variation becomes thereby a theme."
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