Hi,

A photon is the quantum of electromagnetic radiation. The term quantum is the smallest elemental unit of a quantity, or the smallest discrete amount of something. Thus, one quantum of electromagnetic energy is called a photon. The plural of quantum is quanta.

The concept of photons and quanta comes from quantum mechanics and quantum theory. Quantum mechanics is a mathematical model that describes the behavior of particles on an atomic and subatomic scale. It demonstrates that matter and energy are quantized, or come in small discrete bundles, on the smallest scales imaginable. A photon propagates at the speed of light.

Hope it helps.

Hi,

A photon in physics, is a basically a bundle of electromagenetic energy and is also the basic unit that makes up light. It does not contain any mass or charge since it is only a particle of light.

Whenever an electron falls from a higher energy level to a lower energy level, a photon is produced and emitted.