Radio waves wavelength
> 10^6 to 10^-1 m
Microwaves wavelength
10^-1 to 10^-3 m
Infrared wavelength
10^-3 to 7 x10^-7
Visible light wavelength
7x10^-7 to 4x10^-7
Ultraviolet wavelength
4x10^-7 to 10^-8
X-rays wavelength
10^-8 to 10^-13
Gamma rays wavelength
10^-10 to < 10^-16
Gamma and X-rays overlap
10^-10 to 10^-13
Waves are classified by their source - X-rays are emitted by fast moving electrons, whereas gamma rays come from the unstable atomic nuclei