[physics]
The range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies. The entire spectrum ranges from frequencies below one hertz to above 1025 hertz. This frequency range is divided into bands characterized by their frequency properties and sensor capabilities, starting with short wave to longer wavelengths, gamma rays, X-rays, ultraviolet, visible light, infrared, microwaves, and radio waves. The estimated limit of short wavelengths is the Planck length; there is no known limit for long wavelengths.