What do white lettering and symbols on the roadway supplement?

White lettering and symbols on the roadway are designed to supplement signs and signals by providing additional information necessary for safe driving. These markings are crucial for guiding drivers, indicating specific actions or behaviors that are expected on the road. For instance, directional arrows can indicate the proper lane to take, while words like "STOP" or "YIELD" reinforce the commands given by nearby signs. This synergy between roadway markings and signs helps to maintain clear communication with drivers, ensuring they understand right-of-way rules and other critical driving instructions.

In contrast, while traffic lights govern the flow of traffic, they are managed independently from road markings. Description of road conditions might also be found in different forms, like signs or electronic displays, but not specifically in white lettering on the roadway. Pedestrian instructions typically rely on different markings or signage intended for pedestrian safety, distinct from vehicle-oriented roadway markings. Therefore, the primary purpose of the white lettering and symbols is to enhance and clarify the information conveyed by existing signs and signals, making them crucial for effective traffic management.