Law

Law is the set of enforced rules under which a society is governed. Law is one of the most basic social institutions-and one of the most necessary. No society could exist if all people did just as they pleased without regard for the rights of others. Nor could a society exist if its members did not recognize that they also have certain obligations toward one another. The law thus establishes the rules that define a person's rights and obligations. The law also sets penalties for people who violate these rules, and it states how government shall enforce the rules and penalties. However, the laws enforced by government can be changed. In fact, laws frequently are changed to reflect changes in a society's needs and attitudes.

In most societies, various government bodies, especially police agencies and courts, see that the laws are obeyed. Because a person can be penalized for disobeying the law, most people agree that laws should be just. Justice is a moral standard that applies to all human conduct. The laws enforced by government have usually had a strong moral element, and so justice has generally been one of law's guiding principles. But governments can, and sometimes do, enforce laws that people believe to be unjust. If this belief becomes widespread, people may lose respect for the law and may even disobey it. But in democratic societies, the law itself provides ways to amend or abolish unjust laws.

This article discusses the main branches of law, the world's major legal systems, and the methods that democracies use to change laws. Many separate World Book articles provide detailed information on topics related to law. For a list of these articles, see the Related articles at the end of this article.

Some Laws are:

• International law
• Constitutional and administrative law
• Criminal law
• Contract law
• Tort law
• Property law
• Common law and equity