One of the popular forms of 18th-century music was the sonata form. This form allowed the music to be balanced and orderly. The sonata form had three parts, the exposition, the development and the recapitulation. In each part there are two themes. As the song plays, the theme changes from what it started with in the exposition and then returns to it in the recap. This creates balance in the musical piece and creates a feeling of satisfaction in the listener. An example of a musical piece that uses the sonata form is "Eine Kleine Nachtmusik, K" by Wolfgang Amadeus Mozart..525