A key with a key light function comprising at least one light source (5), a storage circuit (20) for storing at least one code sequence, and a driver unit (10), which converts the stored form of the code sequence into a driving output for the light source (5), wherein the code sequence can be emitted by the light source (5) at a wavelength visible to humans by means of a temporal or color variation of the luminous flux, and the light source (5) can also be used as an orientation light.