The phenomenon where light is absorbed and re-emitted by a material is called fluorescence. In this process, a material absorbs photons of light, elevating electrons to a higher energy state. When these electrons return to their ground state, they emit light of a longer wavelength than the absorbed light. This characteristic is widely utilized in technologies such as fluorescent lamps, biological imaging, and security applications. Fluorescence is distinct from phosphorescence, where the emitted light persists for a longer duration after the excitation source is removed.