Law is a set of rules and institutions that regulate behaviour in society. It is generally enforceable through governmental authorities, though some systems are privately enforced, as in the case of contract law or family law. It is a source of scholarly inquiry, addressing questions of history, philosophy, economics and sociology.
It serves a variety of purposes in the society that it governs: it keeps the peace, it maintains the status quo and it ensures the rights of individuals. It is also an important vehicle for social change, although the means employed are inevitably different from nation to nation. An authoritarian government, for example, may keep the peace, but it will often oppress minorities and other political opponents, as in Burma or Zimbabwe.
Unlike other scientific theories of phenomena, which are descriptive and empirical in nature (such as the law of gravity or the law of supply and demand), laws about people and human actions have an implicit normative character, as they tell people how they should behave. This complicates the role of the legal system in a society and makes it distinct from other sciences.
In the modern world, laws are typically created and enforced through legislative statutes or regulations, executive decrees or administrative codes and judicial decisions that bind lower courts and future judges under the doctrine of stare decisis. However, in some places, religious or customary law is recognised as binding and has a significant impact on everyday life.