Cantus is a term that refers to a musical piece or a melodic line, often used in the context of choral music. It can also denote a specific style of singing or composition that emphasizes harmony and vocal interplay. In many traditions, cantus serves as the foundation for more complex musical arrangements. In the realm of music theory, Cantus Firmus is a related concept where a fixed melody is used as the basis for polyphonic compositions. This technique has been prominent in various historical periods, particularly during the Renaissance and Baroque eras, influencing the development of Western classical music.