Law is a set of rules created by the state which forms a framework to ensure a peaceful society. It is enforced by mechanisms created by the state and sanctions can be imposed when rules are broken or breached. It serves many purposes but the four principal ones are establishing standards, maintaining order, resolving disputes and protecting liberties and rights.
The definition of law is often a matter of debate and many books have been written which contain numerous different ideas about it. One of the most common themes is that it consists of commands, backed by the threat of sanction from a sovereign, to which individuals have a habit of obedience. This concept grew out of the utilitarian philosophy of Jeremy Bentham and became dominant until the 20th century. It was challenged by natural lawyers such as Jean-Jacques Rousseau and then reshaped by Max Weber and others who questioned whether legality was intrinsically moral.
Other important considerations in the law definition are the purpose of a law and its relationship to social issues. For example, a law might be considered by some to be an expression of a moral code that people should follow and by others to be a tool for gaining power or control over individuals. This is an idea that has been reflected in the development of various political systems throughout history.
While laws exist in all societies they vary greatly depending on the type of society and the culture within it. This is true even of western countries which have their own versions of legal system and traditions. For example, the legal system in the United States has a number of different areas which are covered by laws such as bankruptcy law; commercial transaction law; family law; insurance law; maritime law; property law and tort law.
Some of these laws are federal and some are state or local. Federal law traditionally focuses on areas which were expressly granted to the federal government in the Constitution such as the military, money, foreign affairs (especially international treaties), tariffs and intellectual property. Since the start of the 20th century however, broad interpretations of the Commerce and Spending Clauses in the Constitution have allowed the growth of federal law into a variety of areas such as aviation, telecommunications, railroads, pharmaceuticals, antitrust and trademarks.
Tort law, for instance, covers the entire imaginable spectrum of wrongs which people can inflict on each other and partially overlaps with crimes that are punishable by criminal law. Other laws, such as administrative law and constitutional law, are primarily state or local. A further area of law that is growing in importance is public sector or regulatory law which covers issues such as water law, air law and energy law. This type of legislation is often created by agencies and committees of both the state and the federal governments.