In acoustics and telecommunication, a harmonic of a wave's a component frequency of the signal that 's an integer multiple of the fundamental frequency. For example, if the fundamental frequency's f, the harmonics have frequencies f, 2f, 3f, 4f, etc. The harmonics have the property that they're all periodic at the fundamental frequency, therefore the sum of harmonics's also periodic at that frequency. Harmonic frequencies are equally spaced by the width of the fundamental frequency and can be f… (More on Harmonic)