Law is a set of rules created by governmental institutions that form a framework to ensure a peaceful society. It is enforced by a variety of mechanisms and, if it is broken, sanctions can be imposed. Its precise definition is a matter of longstanding debate, but it is generally described as a science or an art of justice.
Many different legal systems exist and the laws they create are largely determined by what a country’s leaders have in mind for their society. While each nation-state has a constitution for the broad framework, individual countries make additional laws to regulate specific issues in greater detail. These laws are enacted by groups of politicians in a parliament or congress that have been elected (chosen) by the governed peoples to serve as their representatives. In some societies, military or police may also be empowered to enforce the law.
The main functions of law are establishing standards, maintaining order, resolving disputes, and protecting liberties and rights. Laws are a means of regulating behaviour, and they can be enforced by a variety of mechanisms including courts, police, censorship, and prisons. Those who advocate or defend the law are called lawyers. The study of these systems of laws is known as law and legal studies.
Any law that is formally introduced and approved by a government is considered a public law. In the United States, ideas for new laws are usually referred to as bills and are numbered in order of their introduction during each Congress. A bill becomes a law, or is “enacted,” when it is approved by both the House of Representatives and the Senate.
The law is complex and requires research and analysis to determine how it applies to a particular situation. For example, in a common law jurisdiction, one first has to find any relevant statutes or cases. Next, the lines drawn and reasoning of past decisions must be distilled to see how they might apply to the facts of a present case. Finally, the judge must incorporate all of the information and arrive at a decision. This reliance on the law’s precedents is an important strength of common law systems and helps to ensure that there are relatively consistent interpretations of the law. It also contributes to the robustness of commercial systems in countries that follow this system. These differences in legal systems are examined in articles on different types of law, including civil law and Islamic law. For further reading, see legal philosophy; law and society; and law and economics.