Law is a system of rules that a society or government develops in order to deal with crime, business agreements and social relationships. Its precise definition is subject to debate and the term often has several different meanings. It can also be used to refer to a specific branch of the law, such as criminal or commercial law, or it can mean the legal field in general, including the profession of lawyers and judges.

The most common view of law is that it is a manifestation of societal beliefs and values. In this view, when a group of people believe that certain procedures or rights should be in place, their representative lawmakers act to bring about a rule effectuating those societal values, in the pursuit of ensuring that their society functions smoothly. This is a broad and often controversial view of law, as it is not always easy to separate the laws of a nation from the political, social, economic, and cultural influences that are exerted upon it.

A more scientific understanding of law focuses on the fact that laws arise from the behavioral and psychological characteristics of individuals, according to this theory. This is a view that seeks to examine the motivations of the administrators of law in an attempt to understand how they come up with their conclusions, and it stands in direct opposition to theories that focus on examining the underlying principles of the natural world in an attempt to determine why things happen as they do.

Regardless of which philosophical approach to the nature of law is chosen, it is clear that laws are important to societies and individuals. In addition to establishing standards and maintaining order, they protect basic individual liberties and rights, such as freedom of speech and equality. They also provide a framework for resolving disputes and conflicts, as well as providing a mechanism to punish offenders.

In the context of a country, its laws are defined by its constitution and its governing body. These can include the parliamentary procedures that are followed by its legislature and the courts that administer justice. In the United States, the federal and state governments share responsibility for making laws, with some powers being reserved to the individual states. This structure varies widely from other nations, and there is even significant variation within a single state, with some cities having more power than others.