"Blue lights" typically refer to the blue-colored lights used in various contexts, such as emergency vehicles. In many countries, police cars, ambulances, and fire trucks use blue lights to signal their presence and alert other drivers to yield or move aside. These lights are often combined with other colors, like red, to enhance visibility and indicate urgency. In addition to emergency services, blue lights are also used in some public spaces for safety and security. For example, blue light emergency phones are installed in parking lots or campuses to provide a quick way for individuals to call for help. These lights serve as a visual cue that assistance is available nearby.