A set of rules that a society or government develops to deal with things like crime and business agreements. People have to follow these laws or risk being punished, such as fines or imprisonment. The term law can also refer to a specific type of law, such as traffic laws or banking regulations.

Different philosophers have described the purpose and function of law in different ways. Some, like Dean Roscoe Pound, see it as a means to fulfill social needs and ensure that people are treated fairly by the state. Others, like John Erskine, argue that it reflects natural rights that are not dependent on enforcement or social convention. And still others, such as Hans Kelson, believe that there is a hierarchy of laws, with the highest one known as the grundnorm.

When a judge interprets a law, he or she tries to find out its true intent when it was first passed. This is known as originalism or textualism. Some judges use this method of interpretation because it allows them to avoid changes in social conditions by following the original intention of the framers of a law. Others prefer to derive principles from the law and apply them to new circumstances.

Lastly, some judges try to be consistent in their decisions by following precedents from previous cases that have similar facts. This is called internal consistency.