F ouverture, = opening. Instrumental composition as an introduction or opening to a stage or larger choral work, e.g. to an opera, play, ballet, oratorio or cantata. From the middle of the 18th century onwards it was a single movement, often with programmatic ideas. Beginning with Beethoven, in the 19th century, the overture shed its specific purpose to become a symphonic genre in its own right for the concert hall.