Final answer:
The purpose of the pedestrian crossing sign is to alert drivers of pedestrians crossing the road. The sign is typically rectangular with a white background and a black silhouette of a person walking.
Step-by-step explanation:
The purpose of the sign is to alert drivers that pedestrians may be crossing the road at that location. The shape of the sign is typically rectangular with a white background and a black silhouette of a person walking. This shape is easily recognizable and stands out on the road, helping drivers to quickly identify the presence of pedestrians and be cautious.