In a canon, the theme presented by one voice is imitated by the other voice or voices. A canon can be a complete musical work, or it can be used as a counterpoint technique in a piece of music. Below is a very simple canon by Konrad Max Kunz:

There are many types of canons. The imitation of the first voice might be at the octave or at any other interval (2nd, 3rd, 4th, etc.). Besides, the imitation might use inversion, retrograde motion, augmentation or diminution.

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