Most popular music is based on song form, but classical music has many different forms, some of which can be used over a long time span to make big compositions. Classical music can have many forms, including the symphony, concerto, oratorio, opera, sonata, fugue or any combination of dance movements such as suites. In many of the longer compositions, short tunes are developed and changed during the course of the piece. Beethoven’s Fifth Symphony is a good example of a piece which develops from just four notes into a large piece lasting about half an hour.