Hertz (Hz): This is a unit used to measure frequency, like beats per minute in music.
Period: As mentioned earlier, this is the time taken for one complete cycle or wave oscillation to occur. It's inversely related to frequency - if you have a high-frequency song with lots of beats happening quickly, each individual beat (or period) is very short!
Photon: A particle representing a quantum of light or other electromagnetic radiation. A photon carries energy proportional to its frequency but has zero rest mass. Like dancers moving at different speeds on a dance floor, photons move at frequencies that determine their color and energy level.