It’s the law , but which law-federal or state law ? In the United States , there are different layers of laws . At the top is federal law , which Congress makes for all people in the United States . Then each state makes laws about things in its territory . The laws that each state makes must not go against federal laws . Counties and towns also make rules . A town may require that you have a license for your bicycle , for example . Here are some similarities and differences in state laws .