Law shapes politics, economics, history and society in many different ways. It serves as a mediator between people and their disputes and governs people’s behaviour in society. It is also a source of scholarly inquiry into the fields of legal history, philosophy, economic analysis and sociology.

The main purposes of law are to keep the peace, maintain the status quo, preserve individual rights, protect minorities against majorities, promote social justice and provide a mechanism for orderly social change. However, laws can have a wide range of effects and some systems of law may serve the interests of one group more than another. For example, authoritarian regimes may be effective at keeping the peace but they might repress minority groups or oppress political opponents. In contrast, democratic systems may be less efficient at keeping the peace but they are more likely to uphold the rights of all citizens.

Laws are enacted by governments and enforced by courts or other state institutions. They can include any national, supranational, federal, state, provincial or local statute, constitution, common law, code, order, ordinance, rule, regulation, treaty (including income tax treaties), licence, permit, authority, approval, consent, decree, injunction, binding judicial interpretation or other requirement, enacted, adopted, promulgated or issued by a Governmental Authority.

There are many branches of law, which broadly fall into three categories for convenience, though the subjects often intertwine and overlap. Contract law regulates agreements that exchange goods or services and covers anything from buying a bus ticket to trading options on the derivatives market. Property law determines people’s rights and duties toward their tangible and intangible possessions, such as land or a car, but also money and shares of stock. Criminal law deals with conduct deemed harmful to social order and involves penalties such as imprisonment. Civil law, on the other hand, resolves lawsuits between individuals and companies and organisations.

While the law defines how a society should function, it is up to its citizens to decide whether they want to live according to those laws. This is a dynamic process and the relationship between a society’s law and its values is a subject of continuing debate.

While some commentators seek to limit the scope of law to the rules created and enforced by a sovereign state, others argue that the law extends to any system of morals, ethics and principles that a community recognises as binding. This is a key argument in favour of a liberal approach to the concept of law.