Franz Joseph Haydn (1732 to 1809) was an Austrian composer of the Classical period. He was instrumental in the development of chamber music such as the piano trio. He composed for a multitude of instruments and arrangements. Haydn is closely associated with the Broadwood piano firm who offered him a studio at their nearby London factory.

A central characteristic of Haydn's music is the development of larger structures out of very short, simple musical motifs, often derived from standard accompanying figures. Haydn's work was central to the development of what came to be called sonata form. His practice, however, differed in some ways from that of Mozart and Beethoven, his younger contemporaries who likewise excelled in this form of composition. Haydn was particularly fond of the so-called monothematic exposition, in which the music that establishes the dominant key is similar or identical to the opening theme. Haydn also differs from Mozart and Beethoven in his recapitulation sections, where he often rearranges the order of themes compared to the exposition and uses extensive thematic development.

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