Law is a body of rules set by a controlling authority, such as a government, which people must follow or face punishment. It is a way to maintain peace and order in society and to make sure everyone receives the same rights and privileges. It is also a means of resolving disputes between individuals and between nations. Laws can be written or oral, and they are generally enforced by police or government agencies. The word law is sometimes used to describe the entire legal system, or a particular field of law, including criminal and civil law, contract, torts, real estate, and intellectual property law.
It is important that laws be clearly defined, so people know what they are supposed to do. They should also be reasonably stable over time, so that people can plan ahead and know what the consequences of their actions will be. For example, murder is against the law in most places, and if someone commits the crime they can expect to be punished.
There are many purposes for laws, but they generally serve four main purposes: establishing standards, maintaining order, resolving conflicts, and protecting liberties and rights. They can be created by a group legislature, resulting in statutes; by the executive, resulting in regulations; or by judges through the principle of stare decisis, in common law jurisdictions. Private individuals may create legally binding contracts, such as arbitration agreements, that are alternative ways to resolve disputes to standard court litigation.
Even in a well-ordered society, conflict is inevitable. The law provides a way to settle those conflicts without violence, by making it possible for the courts to decide who is right. For example, if two people claim the same piece of land, the court can decide who has the right to it, based on documents such as deeds or title certificates. Other areas of law include family, criminal, employment, and commercial law.