Pavement Markings 40/ 42
California

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It is advised to drive in the lane with the smoothest flow of traffic. If you can choose, pick the middle lane for driving. If there are only two lanes, pick the right one and leave the left one for passing.
Left lane serves for driving faster, passing or turning left. Right lane servers for driving slower, enter or turn off the road.

You should not change the lanes too frequently. Stay in one lane as long as possible, especially when going through intersection. Last minute turn can cause accidents.