Hertz
One ‘cycle per second’ is often termed one ‘Hertz’ after the German physicist.
Standard scientific prefixes are used so 1000 cycles per second is 1000 Hertz (1000 Hz) or 1 kiloHertz (1kHz).
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Harmonics
In addition to the fundamental frequency of a vibration there are also superimposed additional frequencies at 2x, 3x, 4x etc in theory all the way to infinity! The 2nd harmonic is 1 octave higher at twice the frequency. Middle ‘C’ on a piano is at 261.626 Hz.