Law is an important part of any society and governs people in many ways. It shapes politics, economics and history, and mediates relations between people. Generally speaking, law is either a set of rules written down and consolidated into an official document called the code (for example, the United States Code) or a compilation of decisions in cases that have been heard before a judge, referred to as case law. Law can be religious in nature, as with Islamic Sharia law, or it may be secular, such as the laws of physics.
The purpose of law is to promote public welfare and to maintain social order in a peaceful manner by resolving disputes between individuals and among private and public groups or entities. It can also be used to ensure that people have the same rights, responsibilities and privileges, which are enforceable by government and private institutions alike. Law can protect property, prevent criminal activity and provide for the safety of citizens. It also regulates and limits activities such as advertising, censorship and war.
From a methodological point of view, law is unique in comparison to other sciences and disciplines. In particular, it is normative rather than descriptive. Normative statements in law are those that describe how people ought to behave or which behaviour is acceptable. This is in contrast to empirical statements, such as those found in the natural world or in social science, which are descriptive and causal (e.g. the law of gravity).
The nature of law varies from country to country, with some having civil law systems that have been codified and consolidated by legislatures, while others use common law systems where judges make precedent decisions, which are later collected into a body of law known as case law. In a few nations, especially those that have adopted the rule of law, there is a combination of both, where the legislative and judiciary branch of government makes law and applies it equally to all.
Despite the differences in legal systems, most of the world’s countries have some form of rule of law. This is a system of governance in which government and private actors are held accountable under laws that are clear, publicly promulgated and stable and apply evenly. It also includes the principles of supremacy of the law, equality before the law, participation in decision making and transparency, independence of adjudication, and access to justice.
The most prominent legal subjects are contract law, which regulates agreements between two parties; property law, which covers ownership of tangible assets, such as land or buildings; and evidence law, which concerns the rules that must be followed for a trial to be fair. However, the study of law is far broader than these three areas. The scope of law includes such diverse subjects as international law, administrative law and human rights. Moreover, the law encompasses both public and private law, and is applied at local, state, national and international levels.