What does a white circular sign with a red border signify?

A white circular sign with a red border specifically signifies a "Do Not Enter" sign. This sign is used to inform drivers that they are not allowed to enter a particular roadway or area, helping to prevent collisions by clearly indicating prohibited access. The red color and circular shape are universally recognized in traffic signage, assisting in the quick recognition of important warnings on the road.

In contrast, a yield sign generally takes the shape of an inverted triangle and is colored in white with a red border, indicating that drivers should yield to oncoming traffic. A speed limit sign is typically rectangular and displays the maximum speed allowed, while a stop sign is octagonal and requires drivers to come to a complete stop before proceeding. Each of these signs serves a distinct purpose in the traffic system, ensuring safety and traffic regulation on the roads.