Law is a set of rules that governs the conduct of people and their relationships with one another. It is enforced by a controlling authority and embodies the principles and policies of the community, either in written statutes or in unwritten custom and tradition. It shapes politics, economics and history in many ways and serves as a mediator of relations between people.
The study of law involves the research and analysis of legal rules, systems and processes. It covers areas as diverse as property and criminal law, human rights and corporate governance. The main goal of law is to achieve social cohesion and peace, but it also has many other objectives:
Some jurisdictions use religious precepts as the basis for their laws. Examples include Jewish Halakha and Islamic Sharia. However, even in religious jurisdictions, further human elaboration of these basic precepts is required to provide comprehensive legal systems, such as through interpretation, Qiyas (reasoning by analogy), Ijma (consensus) and precedent.
Most countries employ a common law system. This means that the law is derived from judicial decisions of past cases. This makes the law more malleable than statutory law and allows judges to reinterpret the law to respond to changes in political, legal or social philosophy. Judges will also often give lengthy reasons for their decision and this helps to ensure consistency and predictability.
Other jurisdictions have a civil law system that relies on codes to determine what the law is. These are typically more rigid and do not allow judicial flexibility. The result is that parties have less a priori guidance in civil cases and proceedings can be far longer, because fine points are decided anew each time.