Law is a system of rules created and enforced by social or governmental institutions to regulate behavior. Its precise definition is a matter of longstanding debate and has been variously described as a science and as the art of justice.
Regardless of its precise definition, the law shapes society in a variety of ways. It defines standards for behaviour, maintains order, resolves disputes and protects liberties and rights. It can be state-enforced and made by a collective legislature, resulting in statutes, or by the executive through decrees and regulations, or it may be judicially established through case law, as is common in civil law jurisdictions. It can also be privately-enforced and enforceable through contractual agreements, arbitration or other forms of alternative dispute resolution.
It is also important to distinguish between laws that are enforceable and those that are just. To be enforceable, they must comply with the rule of law: a principle of governance under which all persons, institutions and entities, public and private, are held accountable to laws that are publicly promulgated, equally enforced and independently adjudicated. It also requires adherence to the principles of supremacy of the law, equality before the law and accountability to the law, separation of powers, participation in decision-making, legal certainty and avoidance of arbitrariness.
Other branches of law include contract law (dealing with exchanges of goods or services), property law (defining people’s rights and duties toward tangible property such as land or buildings, movable property like clothing and cars, and intangible assets such as bank accounts and shares of stock) and administrative law, covering the rules and procedures for government and businesses.