Driving in America

We have cars having a handle at right side and drive left roads in Japan. In contrast, they have cars having a handle at left side and drive right roads in America. At first, I was perplexed in such a difference. But only three days later, I got used to the American style.
 Basically, I can drive my car without a fatal trouble in America now. However, I am sometimes bewildered in the different rules between Japan and America. For example, we can turn right even in the case of a red signal in America, which is very different from the rule in Japan. Even then, there are some places where the turning right on a red signal is prohibited. So I am always confused in turning right at red signals.
 Anyway, there is an only rule that is not different between Japan and America. The most fearful matter during driving cars is police cars.