Law is a set of rules or principles that governs the actions of a person or group. Its purpose is to establish standards of conduct, maintain order, resolve disputes and protect liberties and rights. The most important function of law is defining what is right and wrong, or what one may and cannot do. Law also serves to delineate the boundaries between a person and their society. Laws are the product of a process that includes enactment, application and review.

The discipline of law is a source of study for many academic fields, such as history, philosophy, sociology and economics. It is also a focus of professional development for lawyers and non-lawyers alike, and is a source of social controversy. Law is a vital component of any civilized society, and the existence of laws helps create a safe and secure environment.

Most people’s lives are governed by law, in the form of legislation and regulations passed by governments and enforced by courts. The most important laws are those that guarantee fundamental human rights, such as the right to life and freedom. Laws that regulate commerce and business, such as contracts, taxation and property ownership, are also important. Laws that protect public health and safety are also vitally important to most societies.

In “common law” legal systems, decisions by judges or barristers bind lower courts and future judges, and are recognized as “law” on an equal footing with statutes enacted through the legislative process and regulations issued by the executive branch. The principle is known as stare decisis. In contrast, in civil law systems, legislative statutes are more detailed and judicial decisions are less binding, because the judge or barrister is writing to decide only the particular case at hand.

The law covers a multitude of topics and varies greatly from country to country. Some countries, such as Egypt and the former colonies of continental European nations, have retained elements of their civil law traditions. Other parts of the world, such as China and India, have a mix of civil and common law. In still other places, such as Japan and New Zealand, the civil law has been replaced by a legal system modeled on Western law.

The most widely recognized types of law are criminal and civil. Criminal law deals with behavior that harms a person’s reputation or the well-being of others, and can be punished by imprisonment or fines. Civil law, on the other hand, deals with disputes between individuals. Examples include disputes about property, such as a disagreement over who owns a house or car, and cases in which someone is harmed by another person’s conduct, such as an automobile accident or defamation. In these cases, the victim can sue the offender for compensation. This type of law is commonly called tort law. Other areas of law include administrative law, constitutional law and international law. For more information about law, see the articles on the following pages: