Which lane is commonly used for passing vehicles on multi-lane roads?

The left lane is commonly designated for passing vehicles on multi-lane roads. This convention exists because it provides the safest and most efficient way for faster-moving vehicles to overtake slower ones without causing disruption to the flow of traffic. By utilizing the left lane for passing, drivers can maintain a smoother traffic pattern and minimize the risk of collisions caused by frequent lane changes.

On multi-lane roads, the right lane is typically used for slower traffic or for vehicles preparing to exit. The middle lane may serve various purposes, depending on the specific road and traffic conditions, but it is not specifically designated for passing. The use of any lane for passing could lead to confusion and unsafe maneuvers, especially if drivers are not clearly aware of which lane is meant for overtaking. Thus, adhering to the practice of using the left lane for passing helps maintain order on the road and enhances overall safety.