The law is the set of principles geared to control human behaviour and keep societal order. It has four main purposes: establishing standards, maintaining order, resolving disputes, and protecting liberties and rights.
Laws may be established by a group legislature, resulting in statutes; by the executive through decrees and regulations; or by judges through precedent, referred to as case law. These laws may be based on social and economic considerations as well as morality, religion or philosophy. The exact nature of the law reflects the particular history and culture of an individual nation.
Some nations, such as the United States, employ a common law system, in which laws are derived from judicial decisions made in legal cases, rather than from written statutes. This means that a judge’s decision in one case can impact the outcome of future cases, even if those cases deal with different facts. In contrast, other countries, such as Japan, use civil law systems, in which judges base their decisions on codes that explicitly specify the rules to be used in a case.
Other areas of law include labour law, which studies the tripartite industrial relationship between worker, employer and trade union, including collective bargaining and the right to strike; administrative law, which concerns the activities of a government agency such as the IRS; and evidence law, which defines what materials are admissible in court cases. Laws also cover the rights of individuals and groups, such as family law, encompassing divorce proceedings and custody of children; property law, which governs the ownership of land; and environmental law, which protects natural resources from damage.