Law is a set of rules that are created and enforced by social or governmental institutions to regulate human behavior. It is a distinct field from empirical science (as in the laws of gravity) and social science, as it deals with normative statements about how people ought or should behave and how they should be treated by others.
There are many fields of law, which can be broadly classified as civil, criminal and administrative. Civil law is concerned with disputes between individuals, such as contracts, property rights and torts. Criminal law is concerned with offences against a state or its citizens, such as murder and robbery. Administrative law is concerned with the conduct of government, such as censorship and immigration.
Legal systems vary, with some having more detailed statutes than others. The legal system of the United States, for example, includes a doctrine of case law, whereby previous court decisions govern future cases with similar facts and circumstances. Other legal systems, such as the Islamic Sharia and the Christian canon law, are based on religious precepts.
A common feature of all legal systems is that the authority to promulgate and enforce laws lies with a sovereign entity, such as the national government or a central governing body. The institution that makes law is usually referred to as the “rule of law”: an orderly, predictable, stable and transparent regulatory structure, based on clear, publicly available information; accessible, competent and impartial authorities and processes; and accountability for individual rights, including property, privacy and freedoms.
Law can be studied at a number of educational levels. An introductory course is often required for those who want to become lawyers, though the field also attracts students with degrees in other subjects, such as economics, philosophy and history. Lawyers are regulated in most countries, either through professional membership organisations or government departments. The legal profession itself has a long history of disciplinary action.
There are also specialised areas of law, such as competition law (the modern version of Roman antitrust decrees and English restraint of trade), aviation law, maritime law, medical jurisprudence, labour law, family law and tax law. In addition there are rules of procedure, such as civil and criminal procedure, bankruptcy and evidence law.
Lastly, there is the field of public law, which deals with a variety of issues, such as regulations on the provision of services and utilities, such as water or electricity. This area of law also covers the legal responsibility of private companies who provide these services, for example, in relation to environmental issues and health and safety regulations. This is an increasingly important area of law, as the privatisation of public services becomes more widespread. In addition, laws may be imposed on business activity by government agencies. For example, antitrust laws control businesses who seek to control the price of goods and services in a market. This is known as anti-monopoly law. A company found to be breaking this type of law can be fined by a government agency.