Art of combining different melodic lines in a musical composition.
The term is often used interchangeably with polyphony (music consisting of two or more distinct melodic lines), but counterpoint more specifically refers to the compositional technique involved in the handling of these melodic lines. The first recorded use of two melodic lines simultaneously was in 9th-century treatises showing examples of organum (a type of music for multiple voices), though improvised counterpoint
in which the voices probably moved mostly parallel to each other, and thus failed to convey an impression of independence
may date back to some centuries earlier. The desire to ensure pleasant consonances and avoid unpleasant dissonances when improvising (see consonance and dissonance ) called for principles of simultaneous vocal motion (voice leading). Because the relative movement of voices approaching and leaving given interval s was thought to produce effects that were more or less pleasing, rules were created to govern various types of relative motion. The "vertical" aspect of counterpoint
the relationship between the melodic lines
came to be studied as harmony , especially from the 18th century. Though harmony and counterpoint are intimately intertwined, most of the multivoiced music of the Middle Ages and the Renaissance is considered essentially polyphonic or contrapuntal
that is, consisting of a combination of relatively independent and integral melodic lines. In the Baroque era, with the invention of figured bass and the continuo , the balance began to shift toward a harmonic orientation.