Law shapes politics, economics, history and society in many ways. It can regulate commerce, punish crimes, and protect property; provide for orderly social change; establish rights, privileges, and duties; and determine the legitimacy of power and authority.

In a democracy, laws may be democratically enacted and enforced; in autocracies and dictatorships, the rule of law is often limited by the whims of rulers or the abuses of power. The legal systems of different countries reflect their cultures, history and traditions. Some, like China’s civil and common law systems, are rooted in religion; others, such as Japan’s, draw on Western influence.

One of the oldest and most influential definitions of law is the utilitarian, which defines it as commands backed by the threat of sanctions from an overarching authority to which people have a habit of obedience. Jean-Jacques Rousseau’s concept of natural law, on the other hand, argues that law reflects innate and unchanging principles of morality.

The law is also a discipline and profession that has its own vocabulary: statute, code, regulation, ordinance, or treaty. A person who practices law is called a lawyer. Modern lawyers gain a distinct professional identity through specified procedures (e.g., successfully passing a qualifying examination) and have a special qualification (a legal education earning them a Bachelor of Laws or a Juris Doctor degree). The word “law” also refers to the body of rules governing a particular field of activity; it may be described as common law, case law, constitutional law, criminal law, family law, or tax law, for example.