This document summarizes different types of music that were popular in the Middle Ages. It discusses Gregorian chant, which was religious music sung in Latin without instruments. It also describes secular music called troubadours and trouvers, which used instruments and vernacular languages to sing about courtly love. Additionally, it mentions cantigas de Santa Maria, which were religious songs written in Galician-Portuguese. The document provides an overview of the development of polyphony and instruments that were used in medieval music.