Joke: Right of the road

When I first arrived at the United States, my English was poor. In order to get a driver license, I had to pass a knowledge test first.  In order to pass the knonledge test, I had to study the brochure. I had a hard time understanding the phase “right of the road”.  When I asked a fellow student, he told me, “right of the road means the right side of the road. Every driver must drive on the right side of the road.”  Then, he pondered, “Who will drive on the left side then? Aren’t we wasting half of the road?”