Law is a system of rules created and enforced by governmental or social institutions to regulate behavior. Its precise definition is a subject of longstanding debate, and it has been variously described as a science and as the art of justice. Law imposes sanctions on individuals or groups that violate the rights of others. It can also be used to create economic stability and promote social change. Many laws have unintended consequences. The concept of law is inherently complex and the political landscape varies widely from nation to nation.
A person who practices law is a lawyer. The legal profession is generally concerned with the interpretation and enforcement of legislation, statutes and case law. Lawyers must have good research and analytical skills, as well as the ability to communicate clearly with their clients. They must also understand the complexities of the law, including its technical terminology.
The practice of law involves advising and representing clients in the courtroom, or in negotiations outside the courtroom. Lawyers must also be familiar with the procedures for preparing and presenting cases, and they must be able to identify the most beneficial strategy for their clients. In addition to practicing law, lawyers often teach law students and serve on legal advisory boards.
In the United States, the legal system is based on common law. This means that judges decide cases based on prior decisions and the reasoning behind those decisions. This is known as the doctrine of precedent or stare decisis. In a legal system that uses common law, decisions of higher courts bind lower courts unless there is a compelling reason to reject the decision or significantly different facts.
Other countries have a civil law system that relies on written code rather than judicial decisions to determine case outcomes. Judges in a civil law system have less discretion, but they must follow the rules set out in the codes. Judges in a civil law system may write briefs for their colleagues explaining why a case should be decided one way or another.
The most important function of law is to define and protect fundamental human, individual and property rights. These include freedom of speech, religion, assembly and travel; equality of sexes and races; privacy and family life; freedom from discrimination; and access to health care and education. In most places, the existence of stable and democratic government is the primary source of these rights. The legitimacy of a government is largely determined by its relationship with the law. A government that fails to fulfill its principal functions can face popular revolts.