The law is a system of rules that a society or government develops to deal with crime, business agreements and social relationships. The word can also be used to refer to the people who work in this system. It is not easy to give a precise definition of law, as different societies and individuals have varying ideas about it. However, a definition is often based on the idea that law is a set of enforceable, binding rules made by a sovereign power and enforced by its agents. It is often also based on the idea that the law is an objective and immutable set of principles, with some sort of moral core.

One way of thinking about law is to consider the principal functions of it: to keep the peace, maintain the status quo, protect minorities against majorities and promote social justice. Different systems of laws can serve these purposes more or less effectively. For example, an authoritarian regime may keep the peace but oppress its citizens. A democracy may maintain the status quo but impose limits on individual freedoms.

Another aspect of law is the fact that it is not possible to prove that it exists or that it contains precepts of such-and-such import, because the shape and limitations of the physical world limit what humans can do or achieve. Therefore, the content of law must be a matter of choice. A common view of legal interpretation is called textualism. This approach, influenced by early 20th century movements like logical empiricism and American legal realism, holds that the meaning of a written text is contained within it.