What is light? For centuries scientists struggled to prove whether visible light behaves like a particle or a wave, until they concluded that it behaves like both. Light, as well as other forms of electromagnetic radiation, such as gamma-rays, X-rays, ultraviolet, optical, infrared, microwave, and radio, can move like waves and carry photons with different amounts of energy. Through the more than 100 years of the Nobel Prize, the Nobel Committees have celebrated many different discoveries and functions that helped to illuminate our understanding of light.