- In the field of optics, light is explained in terms of electromagnetic waves with the properties of wavelength, frequency and energy.
- Light sometimes exhibits wave-like behaviour, at others, it behaves like both waves and particles, and at others just as particles.
- In physics, light is explained in terms of electromagnetic fields that propagate through space configured as bundles of photons.
- Photons are the force carriers of radiant energy (electromagnetic radiation).
- A photon is an elementary particle, a quantum of light (eg. visible light), so a photon is the smallest quantity (quantum, plural quanta) into which light can be divided.