These are the federal courts and the state courts. These are the two main court systems that exist in the United States.
These two court systems are, for the most part, separate from one another. Cases that are in the federal courts' jurisdiction do not have any way of moving into the state court system. Cases that are in the state courts can get to the federal courts. This can only happen, however, in certain types of cases. Mainly, this can occur when one side in a case believes that the state court's decision violates federal law.