(Franz) Joseph Haydn (March 31,1732 – May 31, 1809) is an Austrian composer of the Classical period.

He is instrumental in the development of chamber music such as the piano trio and his contributions to musical form have earned him the epithets "Father of the Symphony" and "Father of the String Quartet".

Haydn spends much of his career as a court musician for the wealthy Esterházy family at their remote estate.

Until the later part of his life, this isolates him from other composers and trends in music so that he is, as he puts it, "forced to become original".

Yet his music circulates widely and for much of his career he ss the most celebrated composer in Europe.

He is a friend and mentor of Mozart, a teacher of Beethoven, and the older brother of composer Michael Haydn.