Ultraviolet (UV) light is a type of electromagnetic radiation with shorter wavelengths than visible light. It is divided into three primary types: ultraviolet A (UV-A), ultraviolet B (UV-B), and ultraviolet C (UV-C). UV radiation has enough energy to break chemical bonds and can cause ionization, a process in which electrons break away from atoms.
UV light is produced naturally by the sun and artificially by sources such as black lights, mercury lamps, fluorescent tubes and LED. It has a variety of uses, including helping people get tans, killing bacteria, creating fluorescent effects, curing inks and resins, and treating medical conditions such as psoriasis[1][2]. Prolonged exposure to UV radiation can increase the risk of skin cancer[2].
Source: [1] clevelandclinic.org, [2] ccohs.ca