Counterpoint is two or three melodic lines played at the same time so that they sound consonant (see consonance). A horizontal structure of melody against melody rather than chords. The term comes from the expression punctus contra punctum (meaning "point against point" or "note against note"). A single part or voice added to another is called a counterpoint to the other, but the more common use of the word is that of the combination of simultaneous parts or voices, each significant in itself and the whole resulting in a coherent texture. In this respect, counterpoint is the same as polyphony.
It can also be used to describe contrasting relationships that exist along another parameter (e.g., rhythmic counterpoint in funk arrangements).
The art of counterpoint developed from the ninth century onward and reached its highest point at the end of the sixteenth century, and the beginning of the seventeenth, and when, at a later date, attempts were made to formulate rules for students of the art they were based on the practice of that period of culmination. The chief theorist responsible for the formulation of those rules was Fux who published, in 1725, a book which still shows its influence in modern textbooks of strict correspondence, a form of training intended to be preparatory to the practice of free counterpoint.
The simplest example of counterpoint is the canon.