Notre-Dame schoolThe Notre-Dame school or the Notre-Dame school of polyphony refers to the group of composers working at or near the Notre-Dame Cathedral in Paris from about 1160 to 1250, along with the music they produced. The only composers whose names have come down to us from this time are Léonin and Pérotin. Both were mentioned by an anonymous English student, known as Anonymous IV, who was either working or studying at Notre-Dame later in the 13th century.
OrganumOrganum (ˈɔrɡənəm) is, in general, a plainchant melody with at least one added voice to enhance the harmony, developed in the Middle Ages. Depending on the mode and form of the chant, a supporting bass line (or bourdon) may be sung on the same text, the melody may be followed in parallel motion (parallel organum), or a combination of both of these techniques may be employed. As no real independent second voice exists, this is a form of heterophony.
Franco of CologneFranco of Cologne (mid to late 13th century; also Franco of Paris) was a German music theorist and possibly a composer. He was one of the most influential theorists of the Late Middle Ages, and was the first to propose an idea which was to transform musical notation permanently: that the duration of any note should be determined by its appearance on the page, and not from context alone. The result was Franconian notation, described most famously in his Ars cantus mensurabilis.
Ars antiquaArs antiqua, also called ars veterum or ars vetus, is a term used by modern scholars to refer to the Medieval music of Europe during the High Middle Ages, between approximately 1170 and 1310. This covers the period of the Notre-Dame school of polyphony (the use of multiple, simultaneous, independent melodic lines), and the subsequent years which saw the early development of the motet, a highly varied choral musical composition.