Light is an energy form that can be absorbed and reemitted by matter. The building blocks of matter, called atoms, serve as “storehouses” for this energy. In an atom, energy can only be stored and then reemitted in packets of varying, but predetermined size.

 However, the size of a packet is typical for one type of atom. Light transports this energy, by bundling together one or more packets of energy to make a “delivery” and sending them off. These delivery parcels of energy are called photons, and a stream of such energy packets is what light is made of.

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