Why do roads have lane markings?
Short answer
Lane markings clarify positions and directions so road users can better predict one another’s movements.
How it works
Lines and symbols on the road communicate traffic regulations and instructions, including lane boundaries and permitted movements. The meaning of colors, shapes, and solid or dashed lines depends on the marking and local rules, so read them together with signs. Slow down when construction or weather reduces visibility.
Key point
Lane markings do more than divide pavement: they give road users shared information about position and movement. Do not rely on the lines alone; also watch signs and surrounding traffic.