The electromagnetic spectrum includes electromagnetic waves with all possible wavelengths of electromagnetic radiation, ranging from low energy radio waves through visible light to high energy gamma rays.
- There are no precisely defined boundaries between the bands of electromagnetic radiation in the electromagnetic spectrum.
- The electromagnetic spectrum includes, in order of increasing frequency and decreasing wavelength: radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.
- Visible light is only a very small part of the electromagnetic spectrum.