Law is the collective set of rules geared to control human behavior and keep societal order. Law covers all areas of human endeavor, from relationships and governance to commerce and individual rights. The broad scope of law is reflected in its numerous branches: contract law regulates agreements to exchange goods or services; property law establishes one’s personal and real ownership conditions and rights; criminal law punishes wrongful acts against society, and so on.

The legal systems of nations are vastly different from one another, and many have evolved over time. The principal functions of law are to keep the peace, maintain social stability and order, protect people’s human rights and property, and guide a nation through change. The success of any law depends on the political power that governs a country; an authoritarian regime may keep the peace and preserve the status quo, but it may oppress minorities or suppress dissent.

The framework of a country’s law may be based on the constitution, which dictates how the government is organized and defines the powers and relationships between various branches. Common law countries use a system of precedent, where decisions by higher courts bind lower courts to assure consistent outcomes on similar matters. In contrast, parliamentary systems are less reliant on this system and typically have an executive branch that works alongside parliament. In either case, the system must be designed to prevent any one individual from becoming so powerful that they can stand above the law.