The document discusses two famous composers:
1. Ludwig van Beethoven (1770-1827), a German composer who went deaf and composed in many genres, including 9 symphonies and 32 piano sonatas.
2. Franz Schubert (1797-1828), an Austrian composer who produced works in various forms including operas, masses, symphonies, and was renowned for his 21 piano sonatas and songs.
The document also defines various musical terms like dynamics, tonality, concerto, and time signature that are used to describe elements in classical music compositions.