The energy units that are necessary for a jump up or that are released in a drop down are called ENERGY PHOTONS.
An atom of an element is made up of many energy levels and electrons move among these energy levels continuously. The lowest possible energy level is called the ground state and for an electron to move from a ground state to an higher energy level energy is needed. When an electron move from an higher level to a lower level energy is released. These energies are called energy photons.
