State Courts
General Jurisdiction
State courts are courts of "general jurisdiction". They hear all the cases not specifically selected for federal courts. Just as the federal courts interpret federal laws, state courts interpret state laws. Each state gets to make and interpret its own laws. This helps the states retain power, and makes sure that the national government does not become too strong.
Federal Courts
Limited Jurisdiction
As the framers wrote the Constitution, some feared that the federal courts might threaten the independence of the states and the people. To combat this fear the framers set up a federal court system that can only hear cases in special circumstances. We call this having“limited jurisdiction.” Since the federal courts can only hear certain kinds of cases, most of the day-to-day cases that courts deal with happen in state courts.
Basically, federal courts hear only 2 types of cases; those that raise a "federal question" and those involving “diversity of citizenship".