What is the main purpose of a speed limit sign?

The main purpose of a speed limit sign is to inform drivers of the maximum legal speed allowed on a particular roadway. Speed limits are established by traffic authorities based on a variety of factors including road design, traffic flow, and safety considerations. When drivers adhere to these limits, it helps maintain safer driving conditions, reduces the risk of accidents, and ensures more efficient traffic movement.

While other options may also provide important information for drivers, such as recommending a safe speed based on conditions or indicating minimum speeds, these are not the primary role of speed limit signs. The focus of a speed limit sign is strictly about setting the maximum speed, which is legally enforceable. This legal aspect is crucial in promoting compliance and providing a clear standard for safe driving.