The document discusses important musical developments that occurred during the Renaissance period, including: 1) The emergence of individualism and expression in music, as well as developments like polyphonic imitation, word painting, and the invention of music printing. 2) The rise of secular music and prominence of the Franco-Flemish style, characterized by equity among vocal parts and a variety of textures. 3) Josquin des Prez emerging as a central figure, renowned for his motets including the famous Ave Maria, which features imitative polyphony across four vocal parts.