Law is a vast subject, covering almost every aspect of human activity. Nevertheless, the core subjects of law can be broadly categorised into three categories for convenience.

Criminal law deals with behaviour that is deemed harmful to the social order and for which people may be prosecuted, convicted and imprisoned. Civil law covers disputes between individuals and organisations, such as divorces, property disputes and legal proceedings. Administrative law, the study of how government agencies make decisions and regulate their activities, and tort law, which examines damage caused by wrongful conduct, are also important areas of the legal system.

In most states, the authority to create and enforce laws is vested in the political leadership of the nation. This means that the law varies from nation to nation, and is often dependent on the shape of the physical world and the limitations of human capabilities.

The normative content of law varies, with some laws being more prescriptive than descriptive (for example, those dealing with the rights and duties of citizens). It is also possible to find laws that are explicitly religious, for instance the Jewish Halakha and Islamic Sharia, both of which have been used as sources of further law through interpretation, Qiyas, Ijma and precedent.

There are also a number of non-normative and purely theoretical aspects of the law that have been developed, for instance, by philosophers, sociologists, economists, historians and social theorists. Among these, the most well-known is the theory of law and reason, founded by John Locke. The concept of the ‘natural law’ is closely related to this theory, and is an area of intense debate.

Modern law is a profession, with its own professional body and various types of qualifications to be gained. Typically, lawyers achieve their distinct professional identity by following a rigorous process that involves passing a bar examination and receiving a qualification such as a Bachelor of Laws or a Juris Doctor degree.

Lawyers are frequently referred to as ‘Esquires’, reflecting the tradition of aristocratic England where such titles were used to denote a legal practitioner of greater dignity than a solicitor. The profession of law has a long history, and it remains a vital component of the structure of human society, shaping politics, economics, history and culture in many ways. The practice of law is also a focus of scholarly inquiry and is a key element in the fields of legal history, philosophy, economic analysis and sociology. It is a complex and fascinating subject which raises profound questions about morality, justice and equality. It is therefore not surprising that it is a very attractive career choice for many young people. The profession of law is also becoming increasingly globalised, with more and more jurisdictions adopting common rules to ease cross-border practice. This has resulted in the development of specialist international law firms. These offer services to both domestic and foreign clients, and have contributed to the growth of multinational corporations. This trend is likely to continue as more countries move to harmonise their systems of law.