Law is a set of rules created and enforced by social or governmental institutions to regulate behavior. Its precise definition is a subject of longstanding debate, with scholars offering different interpretations and explanations of its nature. Some theories of law describe it as a means of social control, while others view it as a tool to serve the purposes of society. The fact that law can coerce its citizens has also been a point of contention; while some philosophers have emphasized this feature, others argue that it is not essential to the concept of law, and that coercion is not pivotal to the functions that laws perform in our societies.
The scope of law is wide; it may include legal disputes between individuals and between groups or organizations, and the responsibilities of government agencies. Law is typically divided into two domains: public law and private law. The former concerns the activities of a state and its citizens, and covers areas such as constitutional law and administrative law; the latter concerns civil disputes between individuals and between individuals and corporations.
Some legal systems, such as the United States, employ a common law system in which decisions made by judges in individual cases are recorded and considered to be law, on par with statutes and executive regulations. This is referred to as the rule of precedent, or stare decisis. In other countries, such as Japan, there are civil law systems that rely on a code of law that explicitly defines the law.