Light is one of the family of radiaotions called the eletromagnetic spectrum. Some types of eletromagnetic radiation are used to transmit information such as computer data, telephone calls and tv siganls.
The electromagnetic spectrum and its uses
frequency type of electromagnetic radiationtypical use wavelength highest gamma radiation killing cancer cells shortest x-rays medical images of bones ultraviolet radiation sunbeds visible light seeing infrared radiation optical fibre communication microwaves
television signAll types of electromagnetic radiation travel at exactly the same speed through a vacuum, 300,000 km/sals