The electromagnetic spectrum describes the full range of electromagnetic radiation in the universe. Electromagnetic radiation is simply another term for light. All light is made of photons, tiny massless packets of space. Photons always travel at the same speed, 299,792,458 meters per second. But some of theirs wavelength are longer than other. If a photon has lower energy. If a photon has a short wavelength and wiggles more frequently, it has hight energy. In this way, a photon is like a football player running down the field to catch a ball. No matter what, he has to be in the end zone in time to catch the ball. If he can run in a fairly straight line, he can get there with relativity little energy.

Radio waves are long wavelengths, low frequency, and low energy form light. Their wavelengths varies from about 1 to 100 meters because they are low