Law is the system of rules that a particular country or community recognizes as regulating the actions of its citizens. Those rules can be enforced through mechanisms created by the state, such as police and courts, and sanctions can be imposed when these rules are broken, such as fines and imprisonment. Law is often viewed as a tool for social control, and some theorists have argued that it is ultimately coercive.

The laws that govern a nation vary between countries, but all legal systems share certain features. In the United States, for example, federal law consists of Acts of Congress, treaties ratified by the Senate, regulations issued by the executive branch and case law decided by the courts. These laws can be divided into two broad categories, procedural and substantive. Procedural law includes such things as the rules for how a trial or appeal should be conducted, while substantive laws include such things as criminal and civil rights.

A person who studies law is called a lawyer or a jurist, and a career in law is becoming increasingly attractive to young people. The study of law covers not only the actual written laws themselves but also the underlying principles and ethics involved in the creation and application of those laws. For example, there are debates about whether it is acceptable to interpret a law in a way that you believe goes against the spirit of its intention or about whether judges should use their own sense of morality when they are considering a case.

The study of law is an important part of the liberal arts and is taught in schools at all levels, from primary school to university. It is important for all students to understand how laws are created and applied, so that they can participate fully in their democratic societies.

Oxford Reference offers concise definitions and in-depth, specialist encyclopedic entries covering all aspects of this vast discipline. Using Oxford Reference, researchers can explore everything from contracts and constitutional law to family and employment law and the major debates in legal theory. Our coverage includes international law, too. In addition, we strive to make our articles as accessible as possible, avoiding technical legal terms and explaining them when they are used. This makes them suitable for both academic and general readers. Our approach is that a good legal article should pass the “grandparent test” – would your grandparents be able to read it and understand what it’s about? If so, then it’s likely to be worthwhile. If not, it needs to be simplified and made more accessible. We also provide comprehensive subject glossaries and indexes to help readers find the information they need.