Law is the body of rules created and enforced through social or governmental institutions to regulate behavior. It can be state-enforced through legislative bodies resulting in statutes, by the executive through decrees and regulations, or established by judges through precedent (called common law). Law can also be privately made through contracts and arbitration agreements.

Law serves a variety of purposes, including establishing standards, maintaining order, resolving disputes, and protecting liberty and rights. Some legal systems serve these purposes more effectively than others. For example, an authoritarian government may keep the peace and maintain the status quo but it can oppress minorities and limit social change.

To become a law, bills must be passed by legislatures. Legislators can receive ideas for legislation from a wide variety of sources. These include other legislators, the National Conference of Commissioners on Uniform State Laws, the Council of State Governments, the American Law Institute, and numerous organizations that produce model laws for legislatures to use. Interests groups can also influence legislation through lobbyists.

The drafting of laws is an art that requires great skill and knowledge. Legislative committees often draft laws after studies and hearings that cover a year or more. The final draft of a bill is then put before the House and Senate for review, research, discussion, and voting.

There are many different fields of law, and a career in law is an increasingly popular choice for college graduates. Some examples of fields of law are administrative law; contract law; criminal law; family law; property law; and tax law.