Law is a system of rules created and enforced through social or governmental institutions to regulate behaviour. Its precise definition has been a matter of debate, with differing theories on the subject having been advanced by philosophers and historians. These range from a philosophy of natural justice to a belief that laws are created and enforced by the will of a deity. Laws can be enacted by legislatures, resulting in statutes, or they may be established through precedent, as in common law jurisdictions. In addition, private individuals can create legally binding contracts and agreements that are enforceable in courts of law.

In modern times, the practice of law is generally overseen by governments or independent regulating bodies such as bar associations, bar councils or law societies. Individual lawyers achieve distinct professional identity through specified procedures such as successfully passing a qualifying examination and being admitted to the bar.

The subjects covered by law are enormously diverse. For example, labour law concerns the tripartite industrial relationship between employer, worker and trade union; criminal law covers a broad spectrum of activities, from murder to fraud; and property law defines people’s rights to tangible and intangible possessions such as land or money.

Other areas include administrative law (rules governing public agencies), constitutional law and public international law. Family law relates to marriage and divorce proceedings, children’s rights and inheritance. Civil rights law involves the protection of citizens’ freedoms and civil liberties, whilst immigration and nationality law concern the right to work and live in a country that is not their own and the responsibilities of citizenship.