Johann Sebastian Bach was a German composer and musician of the Baroque period. He is widely regarded as one of the greatest composers in the history of Western classical music. Bach's compositions include sacred and secular works, such as cantatas, concertos, fugues, and organ music. His music is known for its intricate counterpoint, harmonic richness, and emotional depth. Some of his most famous works include the 'Brandenburg Concertos,' the 'Mass in B minor,' and the 'Well-Tempered Clavier.' Bach's music continues to be studied and performed by musicians and music lovers around the world, making him a true master of his craft.