Peak: The top of a wave
Trough: The bottom of a wave
Cycle: Two consecutive peaks and troughs of a wave
Period: Amount of time it takes for a wave to complete one cycle. (seconds per cycle).
Frequency: How many waves are produced in one second (cycles per second). Often measured in Hertz (Hz), which is equal to 1/s.
Wavelength: The horizontal distance of a cycle (usually in nanometers)

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