Cases have to involve a federal law,( Federal Question jurisdiction) or be between residents of different states (Diversity jurisdiction)

In cases arising under federal law, the federal courts have federal question jurisdiction. Federal jurisdiction can also arise where there is diversity of citizenship between the parties, as where they reside in two different states.

Federal courts have jurisdiction over any case that raises a question of federal law. There are far more than 8 types.

Federal courts have jurisdiction over any case that raises a question of federal law. There are far more than 8 types.