- The electromagnetic spectrum can be defined in many ways. I would say it is seven different transverse wave groups which occur around is in day to day life. The seven different transverse wave (a mixture of electricity and magnetism) groups from bigger to smaller hertz are radio waves, microwaves, infrared waves, visible waves, UVA-UVB-UVC Ultraviolet waves, x-ray waves and gamma ray waves. All waves are non-ionising waves except for x-ray and gamma ray waves which means, they do not have the ability to move through the skin and attack cancer cells and ionising waves (x-rays, gamma ray) have the ability to.