Law is the set of rules that governs human behavior and is enforced by a controlling authority. This set of rules may be written or unwritten. Some laws are implicit in religions such as Jewish halakha and Islamic Shari’ah. Other laws are based on science such as quantum theory. Laws are the foundation for society and their observance promotes order and stability. Law is an academic discipline encompassing philosophy of law, legal history and sociology of law. Law is also a profession involving practice and education.

Historically, most nations developed a legal system based on a combination of statutes passed through legislative processes and decisions made by courts on individual cases. This system is called common law. Judges’ decisions are compiled into a body of rules called case law. In some countries, this system is replaced by a civil law system, in which legislative statutes and regulations are the primary sources of law, with decisions made by judges on individual cases merely adding to or changing existing law.

Other areas of law include patents, trademarks and copyrights; maritime and commercial transactions; contract; criminal and property law. Immigration and nationality law concern the rights of people to live in a nation-state that is not their own and to acquire or lose citizenship; family law covers marriage, divorce, child custody and inheritance; and tax law regulates value added and corporate taxes as well as property and bankruptcy laws.

Lawyers are trained in law schools and earn degrees such as a Juris Doctor (JD), Bachelor of Laws or a Bar Admission Certificate. The title of Esquire is used to signify a person who has been a successful member of the legal profession and Doctor of Laws is an honorific title for those with PhD’s in law.