Law is a system of rules that a society or government creates to regulate its people and their behaviour. The principal functions of law are to set standards, maintain order, resolve disputes, and protect liberties and rights. The nature of law differs from nation to nation. Laws can be based on religious precepts, as in Jewish Halakha and Islamic Sharia or Christian canon law. But most legal systems rely on further human elaboration to provide comprehensive and detailed laws, using methods such as interpretation, Qiyas (reasoning by analogy), Ijma (consensus) and precedent.
The study of law can take many forms, and is concerned with both the actual laws that exist in a particular jurisdiction and the philosophy of law and the sociology of law. For example, the discipline of sociology of law focuses on how laws are created and enforced and looks at the relationship between laws, the social structures that they govern, and their impact on the lives of individual citizens.
Some people also use the term “law” to refer to specific branches of legal knowledge, such as criminology or business law. Other people use the term more broadly to describe the overall concept of law. A general definition of law could be something like: “the totality of all commandments, directives or ordinances that a government adopts and imposes on its subjects, either by force or by persuasion, for the good of the community.”
In some legal systems, courts’ decisions are considered to form part of the law along with legislative statutes and executive regulations. This is called the doctrine of precedent or stare decisis.
Other types of law include property law, which concerns ownership and possession of land or movable objects. The difference between real and personal property is reflected in the law’s terminology: a right in rem concerns a specific piece of land, while a right in personam concerns movable objects such as cars or computers. The law of trusts and companies involves the regulation of corporations and commercial transactions. Aviation law is concerned with all the technical regulations and standards for the safe operation of aircraft, which are framed by national civil aviation acts and are mostly aligned with recommendations or mandatory standards of the International Civil Aviation Organisation.
Those who practise law are called lawyers or solicitors. A lawyer is a person who has been trained to advise clients on the legality of their actions and to assist them in taking steps to comply with the law. Some lawyers specialise in specific areas of law, such as immigration or criminal law. Other lawyers work as corporate lawyers, advising businesses on how to structure their operations and transactions to comply with the law. Increasingly, law schools are also teaching students about the broader philosophical issues surrounding the law and how it should be interpreted and applied. In particular, the law is concerned with morality: Jean-Jacques Rousseau argued that the principle of natural justice is an intrinsically moral philosophy, and utilitarian philosopher John Austin posited that the primary function of the law is to maximise human welfare.