Guillaume Dufay was a prominent composer of the early Renaissance, born around 1397 in what is now Belgium. He is known for his significant contributions to sacred music, particularly in the development of the motet and mass forms. Dufay's work helped to bridge the gap between the medieval and Renaissance musical styles. Dufay's music is characterized by its rich harmonies and use of polyphony, where multiple independent melodies are sung simultaneously. He was influential in the use of secular melodies in sacred compositions, which was a notable innovation of his time. His legacy continues to impact Western classical music.