Law is a system of rules and regulations enforced by a sovereign or other governing body to govern conduct, maintain order, and ensure justice. It is also a system of rights and duties that individuals have toward each other and their property.
Traditionally, laws were based on customs and traditions, but as societies became more modern and more centralized, they developed more formal legal systems. In modern times, laws may be made by a legislature in the form of legislation; by an executive through decrees and regulation; or by courts in common law jurisdictions by precedent (established by judges). Private individuals also can create legally binding contracts and other arrangements that are recognized as enforceable by the state.
The precise definition of law is a matter of ongoing debate, but its main purposes are generally agreed to be establishing standards, maintaining order, resolving disputes, and protecting liberties and rights. Law may be a means of social control, and it is often coercive. For example, police and military forces are commonly regarded as law enforcement agencies because they have the power to use force against people who violate the law. Laws are also used for other kinds of social control, such as censorship, repression, and criminal punishment.
Laws are commonly described as either natural or human, and some philosophers have argued that they reflect unchanging principles of nature and justice. This view gained prominence in ancient Greek philosophy, notably through the work of Lucretius and Plato, and was later promoted by the utilitarian theories of Jeremy Bentham. The idea of natural law also emerged in the 17th and 18th centuries through Jean-Jacques Rousseau, who characterized it as a set of moral imperatives that a rational person should obey.
In addition to serving a range of important social functions, laws are a central element of many business and commercial transactions. For example, contracts are governed by contract law, and the purchase and sale of tangible and intangible property is regulated by property law.
Laws are also an essential part of a well-functioning democracy, as they allow citizens to participate in government and hold public officials accountable for their actions. However, they are a double-edged sword, as they can lead to abuses of power by political elites, which is why checks and balances are so important in the modern world.