Common law is a type of legal system in which the law is created and/or refined by courts on a case-by-case basis. In the United States, it is a body of law that was established in England over many years and is still evolving. Common law developed through decisions of courts and similar judiciaries, rather than through legislative statutes or executive action. The common law is created and refined by judges: a decision in the case currently pending depends on decisions in previous cases and affects the law to be applied in future cases. When there is no authoritative statement of the law, judges have to set a precedent. The body of precedent is called "common law" and it binds future decisions. In future cases, when parties clash in regards to what the law is, an idealized common law court uses past precedential decisions of relevant courts as reference. If a similar dispute has been resolved in the past, the court must apply that resolution strategy to the new dispute (this principle is known as stare decisis). If, however, the court finds that the current dispute is fundamentally distinct from all previous cases, it will decide as a "matter of first impression."