General concepts in the American Legal System
Appellate Court: A court empowered to hear appeals from trial courts. Appellate courts do not repeat the process of fact-finding in a case; rather, they resolve cases by looking at the facts and evidence already entered into the record by trial courts. Federal appellate courts are called the United States Courts of Appeals.
Common Law: Law developed and refined through the resolution of cases by the judiciary. How the case is resolved has precedential effect over future cases to ensure consistency. Though much of federal and state law is codified (i.e. written down in statutes passed by legislatures, and thus binding upon the courts unless they contravene constitutional principles), judicial interpretations of the law are critical to how a law is enforced because of their precedential effect. The courts do not have the power to pass laws. But given the British common law origins of the U.S., there are still many areas of law in which there is no controlling statute, so judge-made common law generally governs; for instance, in contract law.
Constitution of the United States ("the Constitution"): The supreme law of the United States. The Constitution enumerates various powers of the federal government and describes the relationship between the federal government and the states. No governmental body, state or federal, has the power to pass, interpret, or enforce a law in contravention of the Constitution, which can be amended only through a rigorous and long amendment process. Unlike many parliamentary systems, the U.S. Constitution is supreme to the legislature (i.e. legislative/parliamentary supremacy is not a concept in U.S. government). That means Congress or the states cannot pass a bill that is exempted from being constitutional. Note that each state also has its own constitution, but even that is subject to the U.S. Constitution.
Federal Government: Composed of the executive (the presidency), legislative (the Congress), and judicial (the federal courts) branches of the national government, which exercises control over all U.S. foreign policy and certain limited areas, as set forth by the Constitution, of domestic law and policy.
Federalism: The idea that sovereignty is shared between the federal government and the states. There are some powers exclusively reserved for the federal government like over foreign affairs, some types of IP, and interstate commerce. There are also some powers shared between a state and the federal government, and some exclusively reserved for the state. The states generally have broad discretion in exercising power and setting policy within their borders in areas such as education, property rights, crime control and criminal law, corporate formation, bankruptcy law, and family law.
Jurisdiction: The power of a court to preside over litigants and issues presented for adjudication in a case, and render a decision. Without jurisdiction, a court has no ability to properly hear a case. The scope of a court's jurisdiction generally come from statutes (i.e. in laws passed by the legislature); the Supreme Court of the United States is different in that the maximum extent of its jurisdiction is established directly in the Constitution.
Precedent: In common law systems, precedent is established by holdings in previous cases and applied to the case under consideration as a guideline for how to resolve the current case. A court may find that a precedent is binding on the case under consideration; that is, a precedent must be obeyed, especially if it issued from a higher court. For instance, the Supreme Court of the United States, as the highest federal court in the U.S., binds all other courts to its interpretations of the U.S. Constitution. No other court may overrule or reinterpret Supreme Court precedent on its constitutional interpretation. In addition, a court may find that a precedent is persuasive to the case under consideration; that is, a precedent that can be followed, but does not have to be. Whether precedent is persuasive or binding is a complicated question, but fundamentally relates to the jurisdiction of the courts involved.
Separation of Powers: No one branch of government (legislative, executive, and judicial) is supreme to the other branches. Rather, all the branches are able to exercise certain checks and balances over the other branches in order to make sure that no one branch gets too powerful. For instance, the president can veto bills that Congress passes into law, and the federal courts can find that a law is unenforceable because it is unconstitutional.
Trial Court: A court that has jurisdiction to hear matters in the first instance (meaning that this is the court litigants go to first to resolve their issues). Matters can be both criminal and civil. Federal trial courts are called the United States District Courts.
Copyright: The power granted to the creator of an artistic or creative work over its use and distribution, so long as the work is fixed in a tangible medium.
Court of Appeals for the Federal Circuit (aka "Federal Circuit"): The federal appellate court responsible for all patent appeals. The court is unique in that it is not geographic in jurisdiction as in all other federal appellate courts, but rather, oversees appeals relating to specific areas of the law like patents and government contracts. The U.S. Supreme Court is the only court higher than the Federal Circuit.
Patent: A limited right to exclude others from making, using, selling, or distributing an invention without permission in exchange for the public disclosure of that invention.
Trade Dress: A subset of trademark law that protects the look and feel of a product or product packaging. For instance, the look and feel of a Starbucks store (earthy color scheme, wooden countertops and tables) might be protectable under trade dress.
Trademark: A visual or textual mark that serves as an identifier of the source of a particular product or service.
Trade Secret: Any kind of information, substance, design, formula, or process not generally known to anyone that derives independent economic value from not being known to anyone, and is also subject to efforts to keep it secret. For instance, the Coca-Cola formula is a trade secret, and so might a list of a company's clients.