Franz Joseph Haydn was an Austrian composer of the Classical period. He is often referred to as the "Father of the Symphony" and the "Father of the String Quartet" due to his significant contributions to these musical forms. Haydn's compositions are known for their melodic inventiveness, harmonic richness, and formal mastery. He was a prolific composer, producing over 100 symphonies, numerous string quartets, piano sonatas, and operas, among other works. Haydn's music had a profound influence on the development of classical music and continues to be celebrated and performed worldwide.