A court is a body, often a governmental institution, with the authority to adjudicate legal disputes and dispense civil, criminal, or administrative justice in accordance with rules of law. In common law and civil law states, courts are the central means for dispute resolution, and it is generally understood that all persons have an ability to bring their claims before a court. Similarly, those accused of a crime have the right to present their defense before a court.

Court facilities range from a simple farmhouse for a village court in a rural community to huge buildings housing dozens of courtrooms in large cities.

A court is a kind of deliberative assembly with special powers, called its jurisdiction, or jus dicere, to decide certain kinds of questions or petitions put to it. According to William Blackstone's Commentaries on the Laws of England, a court is constituted by a minimum of three parties, namely, the actor, reus, and judex, though, often, courts consist of additional attorneys, bailiffs, reporters, and perhaps a jury.

The term "court" is often used to refer to the president of the court, also known as the "judge" or the "bench", or the panel of such officials. For example, in the United States, and other common law jurisdictions, the term "court" (in the case of U.S. federal courts) by law is used to describe the judge himself or herself.

In the United States, the legal authority of a court to take action is based on three pillars of power over the parties to the litigation: (1) Personal jurisdiction; (2) Subject matter jurisdiction; and (3) Venue.

Jurisdiction

Jurisdiction, meaning "to speak the law," is the power of a court over a person or a claim. In the United States, a court must have both personal jurisdiction and subject matter jurisdiction. Each state establishes a court system for the territory under its control. This system allocates work to courts or authorized individuals by granting both civil and criminal jurisdiction (in the United States, this is termed subject-matter jurisdiction). The grant of power to each category of court or individual may stem from a provision of a written constitution or from an enabling statute. In English law, jurisdiction may be inherent, deriving from the common law origin of the particular court.

Trial and appellate courts

Courts may be classified as trial courts (sometimes termed "courts of first instance", "Original Jurisdiction") and appellate courts. Some trial courts may function with a judge and a jury: juries make findings of fact under the direction of the judge who reaches conclusions of law (called a jury trial) and, in combination, this represents the judgment of the court. In other trial courts, decisions of both fact and law are made by judges (called a bench trial). Juries are less common in court systems outside the Anglo-American common law tradition.