#5: Why the Left Lane Is Not Meant for Cruising
The passing lane has a purpose, although anyone who has spent time on an interstate has probably watched someone settle into it as though they had rented the space for the afternoon. Rules differ across the states, but many require slower traffic to keep right or restrict unnecessary use of the left lane when it is being used for passing. Remaining there can interrupt the natural flow of traffic and encourage impatient drivers to attempt passes on the right.

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