Final answer:
A yellow curb signifies a loading zone or a parking restriction, with different colors on curbs designating specific rules for parking or stopping.
Step-by-step explanation:
When a curb is painted yellow, it indicates a loading zone or another parking restriction. In the context of traffic signs and pavement markings, different colors communicate specific rules to drivers and pedestrians. Yellow curbs typically signal that parking is limited to certain times or for certain purposes, such as loading or unloading goods. On the other hand, a red curb signifies no stopping, standing, or parking at any time, a blue curb denotes handicapped parking, and a white curb indicates short-term parking. It is important for drivers to be aware of these color codes to follow legal parking practices and avoid fines.