On a highway with four or more lanes, which lane should slower traffic always use?

The rightmost lane is designated for slower traffic on a highway with four or more lanes. This lane is typically where vehicles that are not traveling at the same speed as faster-moving traffic should stay, allowing for smoother flow and safer conditions on the roadway. By keeping slower vehicles in the rightmost lane, it minimizes disruptions to the faster lanes and helps prevent accidents that can occur when slower vehicles unexpectedly merge into high-speed traffic.

This organization also enhances the overall efficiency of the highway system. When slower vehicles remain on the right, it allows faster vehicles to pass on the left, thereby reducing the need for frequent lane changes and potential conflicts between vehicles traveling at different speeds. Thus, to ensure safety and maintain traffic flow, slower vehicles are encouraged to use the rightmost lane.