Law is a system of rules created by the state that forms a framework to ensure a peaceful society. If these rules are broken then sanctions can be imposed. Law also refers to the field of study that deals with interpreting and applying these rules, which is commonly referred to as the law profession.

Law has many purposes but four of the most important are establishing standards, maintaining order, resolving disputes and protecting liberties and rights. Law shapes politics, economics, history and society in a variety of ways. This is because the laws of a nation-state can have significant impact on the lives of its citizens and also can affect the interactions between people.

In the case of most countries, a constitution, written or tacit, defines the law and provides a basis for democracy. This gives the people of a country a sense of stability and security, even in the face of changes to the political landscape. Without a stable political environment, the rule of law cannot be established and democracy is impossible to realize.

Various theories and debates on the nature of law have been formulated. Some of the most significant arguments center on whether or not morality is part of law and, if so, how. Other focuses include the extent to which the law is able to protect against anarchy and Hobbesian war of all against all and the ability of the law to guarantee against at least some types of official arbitrariness.

The legal systems of different nations vary enormously, with some relying heavily on religious law while others are entirely secular. In general, however, the rule of law is essential for a society to function effectively. This requires the capacity for people to understand the rules of their society and to know what they are entitled to do, and what they must avoid doing. It also requires a relatively stable set of rules and requirements that are clear, public, and accessible, and which contain determinate and objective standards that are easy to identify and follow.

Some lawyers argue that law is simply power backed by a threat of force and that it can be used to control the behavior of people in any way that the government chooses. Other scholars, however, have emphasized that people who live under a system of law actually do not feel at the mercy of their government because they can vote for and elect the officials who make the law and they are ultimately accountable to the people. Moreover, the existence of checks and balances like a free press, judicial review and freedom of expression help to limit the amount of power that a government can exert over its citizens.