Harmonics

Harmonics are vibrations at frequencies that are multiples of the fundamental. They are characterized as even-order and odd-order harmonics. For instance, the "second-order harmonic" is the fundamental frequency multiplied by two, and is an even-order harmonic. Each even-order harmonic is one octave or x octaves higher than the fundamental; they are therefore musically equivalent to the fundamental. Odd-order harmonics create a series of notes that are musically related to the fundamental frequency—unparallel but resonant with the fundamental, they inform musical scales and give rise to Chords. Harmonics are also called "overtones" or "partials".