The Supreme Court is the highest court that America has in its federal court system. Below them are courts of appeal and below this are district courts.
Individual court systems of each state also exist, and are separate from the federal court system, but they aren’t entirely divorced from the system or independent from it. Each of these individual court systems in each state has its own laws and its own procedures. Each state also has a Supreme Court for the state and they are the final authority on the interpretation of the state’s laws.
A case can move from a state court to the U.S. Surpreme Court when there is a federal question involved.
If you look at the break down of the court system in America, it consists of the following: the Supreme court, 13 courts of appeal, 94 district courts and two courts of special jurisdiction.