The Federal Courts are courts of limited jurisdiction, meaning that they only exercise powers granted to them by the Constitution and Federal Laws. There are several forms of subject-matter jurisdiction, but the two most commonly appealed to are federal-question jurisdiction and diversity jurisdiction. Federal question jurisdiction is available when the plaintiff raises a claim that arises under the laws, treaties, or Constitution of the United States, as opposed to claims arising under state law. By the "Well-Pleaded Complaint" rule, federal question jurisdiction is not available if the federal issue arises only as a defense to a state-law claim. Diversity jurisdiction, on the other hand, is available regarding state-law claims if every plaintiff is from a different state from every defendant (the requirement for so-called complete or total diversity) and the amount in controversy exceeds $75,000.