Law is a system of rules that are created and enforced through social or governmental institutions to regulate behavior. The precise definition of law is a matter of longstanding debate and the subject of many academic fields, including legal history, philosophy, economic analysis, sociology and politics. Law shapes politics, economics, history and society in myriad ways, and it plays a vital role as a mediator of relations between people.

Law encompasses a wide range of areas, from criminal and civil laws to laws regulating marriage and divorce, property, inheritance, the environment and medical jurisprudence. It also includes a host of professional activities, such as advising people about the law or representing them in court. It is a major source of scholarly inquiry into legal history, ethics and philosophy, and it raises important questions about equality and fairness.

Generally, law has two functions: governing and settling disputes. Governmental laws are enacted either by a collective legislature or by a single legislator, resulting in statutes, and they may be interpreted or enforced by the executive through decrees and regulations or established by judges through precedent, normally in common law jurisdictions. The formation of governmental law is influenced by constitutional documents, which set out the rights and obligations of citizens, as well as by the tradition of justice encoded in ancient and modern constitutions. Religious law, such as Sharia, also plays a significant part in some societies.

The prevailing law in a country is usually determined by its political and cultural history, as well as the economic circumstances of the time. Some countries have written constitutions that codify fundamental principles of the state, while others rely on a more informal system of justice, in which case judges decide upon and defend their decisions by citing precedence. The development of law is a process that continues to evolve and adapt in response to changing social conditions.

The law is a complex phenomenon, and understanding it requires a thorough knowledge of the political, economic and historical context in which it exists. A nation’s law serves a number of important purposes, such as keeping the peace and maintaining the status quo, preserving individual liberty and protecting minorities against majorities, and facilitating democratic change. Nations whose governing systems are unstable or authoritarian can fail to fulfill these purposes.