>>11693669hertz is a measure of cycles per second, or events per second. it has units 1/s, meaning anything that can be expressed as a certain number of events per second can be expressed in hertz.
in light, the frequency in hertz refers to the number of wave cycles per second.
in sound, the frequency in hertz refers to the number of sound wave cycles per second
in electronics, frequency in hertz often refers to the number of times the AC current switches direction per second.
if you were to snap your fingers twice per second your finger-snapping frequency would be two hertz
