Lighting is installed on aircraft for a number of reasons including: safety, operational needs, servicing and for the convenience of passengers. The applications of aircraft lights can be broadly grouped into four areas: flight compartment (cockpit), passenger cabin, exterior and servicing (cargo and equipment bays). There are many types of lighting technologies used on aircraft. Lights are controlled by on/off switches, variable resistors or by automatic control circuits. This chapter will review each of these lighting technologies and the type of equipment used in specific aircraft applications.