What does the steady red light for vehicles and aircraft indicate?

The steady red light for vehicles and aircraft serves a crucial safety purpose indicating that one must stop. This signal is universally recognized in aviation and ground transportation as a warning sign. When a steady red light is illuminated, it communicates to drivers and pilots alike that proceeding could lead to dangerous situations, such as collisions or entering restricted areas.

In the context of O'Hare Airport and its surroundings, adherence to this signal is vital for maintaining safety protocols. It ensures that all vehicles and aircraft are aware of their current standing in relation to air traffic or ground operations. Therefore, the correct interpretation of a steady red light is to come to a complete stop and await further instructions or signals before proceeding.