Law is the body of rules and principles a sovereign state or local community establishes to govern its citizens and regulate its interactions. It shapes politics, economics and history. Its defining feature is that it has a normative dimension, prescribing what people ought to do or be allowed to do and limiting what they are permitted to do.

In its narrower sense, law refers to a set of rules made by a country’s legislature, which the citizenry is required to obey or face punishment. It can also refer to the judicial system that enforces those laws and imposes restitution, fines or imprisonment on offenders. The term can be used more broadly to refer to a broad range of legal subjects, including civil law, criminal law and administrative law.

The study of law is multidisciplinary, incorporating philosophy, political science and economics among other fields. Its societal importance stems from the fact that it regulates all aspects of human life, from interpersonal relations to national and international affairs.

As the world becomes more global and complex, legal systems must evolve to address new issues. Some of these issues are specific to a region, while others are universally relevant. International law addresses the relationship of nations with each other through treaties and other instruments, while domestic law deals with the way a state or local government governs its citizens.

Three broad categories are presented for the convenience of discussion, though these subjects intertwine and overlap:

Private law regulates relationships between individuals, such as tort law, which provides compensation if one’s property is damaged, contract law or personal injury laws; and public law, which includes administrative, environmental and labour laws.

Labour law concerns the tripartite industrial relationship between employer, employee and trade unions and includes employment standards, rights to a minimum wage and workplace safety regulations. Civil procedure and criminal procedure are the rules governing how trials and appeals should be conducted, as well as what materials may be admissible in court to support a case.

The basis of some types of law are religious precepts, such as Jewish halakha and Islamic Sharia, which provide guidelines for behaviour and rulings by judges. Other laws are based on historical precedent and social consensus, as in the English common law or the French and German civil code systems. These have the advantage of being easy to export and apply, with a limited amount of detailed case law. These are complemented by other sources of law such as qiyas (reasoning by analogy), ijma (consensus) and jurisprudence.