What sign warns of a sharp curve ahead?

The sign that warns of a sharp curve ahead is a yellow diamond sign with a curve symbol. This type of sign is designed to alert drivers to upcoming road conditions that may require extra caution. The yellow diamond shape is universally recognized for warning of hazards or changes in the road, while the curve symbol specifically indicates that the road will bend significantly, which could affect the driver's ability to maintain control of the vehicle if they are not prepared.

This warning is essential for ensuring that drivers reduce their speed and remain attentive as they navigate through the curve, thus helping to prevent accidents. Other signs mentioned, such as the red stop sign, serve entirely different purposes, such as indicating where drivers must come to a complete stop. The speed limit sign conveys legal limits of speed and does not provide warnings about road conditions. Similarly, green directional signs provide information about directions or distances to locations rather than alerts about driving hazards.