Law is the set of rules that regulates behavior and enforces order in a society. The term also refers to the profession of lawyers and judges who are involved in advising people about the law, representing them in court, and making decisions and punishing offenders.
Different systems of law exist around the world. In the United States, for example, laws are mainly derived from the Constitution and statutes, but there is an important tradition of judge-made law that goes back several centuries—case law. Judge-made law is a legacy of the common law system, in which courts interpreted and applied existing legal principles in each case that came before them.
The fundamental purpose of law is to ensure that all people are treated fairly. The most essential aspects of law include a system of checks and balances to prevent abuse of power by the government, protection of individual rights, social justice, and the preservation of property. These goals are reflected in a wide variety of laws.
Among the most well-known types of law are contracts, torts, property and criminal law. Contract law regulates the exchange of goods and services, from selling a car to writing an essay. Tort law governs civil wrongs, such as injury to person or property and defamation. Crimes and treason are prosecuted under criminal law. Property law establishes the rights and duties of individuals toward their tangible personal possessions, including land and buildings and intangible assets such as bank accounts and stock certificates.
Banking law sets minimum standards for the amounts of capital banks must hold and rules about best practices for investment. Financial regulation aims to control the risk of crises like the Great Depression and Wall Street Crash, which occur when investors overextend themselves. Laws concerning public utilities and services bind private companies to certain levels of social responsibility when they manage a service that is typically provided by the state, such as water, energy, or telecommunications.
Other areas of law include family, immigration, and commercial law. Family law includes divorce proceedings and child custody rights. Immigration and nationality law deal with the rights of individuals to live and work in a nation-state other than their own, as well as the rights to asylum and citizenship. Commercial law encompasses the rules and regulations governing commerce, such as the Uniform Code of Commercial Law and evidence law, which dictates which materials are admissible in court.
The philosophy of law involves questions about the nature of law and the role it should play in society. Bentham’s utilitarian theory of law was that it is a set of commands, backed by threat of sanction, from a sovereign, to whom people have a natural habit of obedience. Other philosophers, such as Rousseau and Aquinas, argued that there are moral laws that impose an innate sense of right and wrong in human beings.