Transcript: Scientists describe the particle nature of light in terms of photons. A photon is like a bullet or a packet of energy carrying electromagnetic radiation from one place to another. The energy of a photon is equal to the Planck’s constant, a tiny fundamental constant of nature, times the frequency. So the energy of a photon is proportional to the frequency. Photons of gamma rays have more energy then photons of x-rays, which have more energy then photons of light. Radio waves have the least amount of energy per photon. The fundamental nature of light can only be described in terms of a mixture of wave-like and particle-like properties. For example, the photoelectric effect cannot be understood unless light is considered as a particle.