Security lighting is part of a complete security system and installed to help protect people and property from criminal activities, and to create a perception of security. Safety and security lighting is designed to ensure adequate illumination to identify hazards or obstructions and to provide safe working conditions and safe passage, while avoiding unnecessary glare, light pollution, or light trespass. A wide range of security lights are used, depending on the needs of the application, in commercial, residential, and industrial facilities such as supermarkets and major retail outlets, parking facilities (lots and garages), schools and institutions, hotels and motels, offices and other buildings. In non-residential applications, security lighting systems are often controlled automatically with time switches, photocells, dimmers and motion detectors.