Law is a system of rules that are created and enforced through social or governmental institutions to regulate behavior. It shapes politics, economics, history and society in various ways. Depending on context, the word “law” can be used to refer to both a set of formal, state-enforced laws and the broader concept of morality that is encoded in human nature or by divine revelation (natural law). The precise definition of law is controversial. It is generally agreed that it includes adherence to laws publicly promulgated, equally enforced and independently adjudicated.

The most basic function of law is to keep the peace, maintain the status quo, preserve individual rights, protect minorities against majorities, and provide for orderly social change. Different legal systems serve these purposes differently. For example, an authoritarian government may keep the peace, but it may also oppress minorities and restrict dissent.

Law can be established by a collective legislature, resulting in statutes; by the executive, through decrees and regulations; or by judges, through precedent, normally in common law jurisdictions. Private individuals can also create legally binding contracts and agreements, including arbitration agreements, that can settle disputes outside of the regular courts.

The study of law and legal systems is known as jurisprudence. Jurisprudence can be divided into two broad areas: 1) the science of law, and 2) the practice of law. The former encompasses all of the professions that advise people about legal matters, represent them in court, or make decisions and punish people. The latter consists of the activities carried out by lawyers, judges and other members of the judiciary.