Which composer's works are known for their complex counterpoint?

The recognition of Bach's works for their complex counterpoint stems from his mastery of interweaving multiple independent musical lines, creating a rich polyphonic texture. Counterpoint involves the simultaneous combination of melodies in a way that they harmonically complement each other while remaining distinct. Bach utilized various contrapuntal techniques, most famously in his fugues and chorales. His compositions, particularly in "The Well-Tempered Clavier" and "The Art of Fugue," exhibit a profound understanding of form and structure, demonstrating intricate relationships between voices.

While composers like Mozart and Beethoven also explored counterpoint, their focus was often on melody and harmonic development rather than the dense and intricate counterpoint for which Bach is celebrated. Vivaldi, primarily known for his operas and concertos, tended to emphasize rhythmic vitality and melody over complex counterpoint. Thus, Bach stands out as the composer whose works epitomize this advanced compositional technique.