Original: An organic light emitting diode (OLED) is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compounds which emit light in response to an electric current.
Simplified: Organic light-emitting diode (OLED) is a type of light-emitting diode (LED). The part of the OLED that creates light is made of a very thin layer of organic compounds.