Law is a system of rules created to ensure a peaceful society. It sets out guidelines on how people should live, work and do business with one another, and also defines punishment for those who break the rules. This is enforced by police and courts. A country’s laws are often written by groups of politicians called a legislature, who are elected (chosen) to make them. They may be based on ancient culture, family and social habits, or on ideas from religious books like the Bible or Koran.

Many of these laws are enforceable by force, so that the government can punish people who break them. This is sometimes known as coercive law. This type of law is a major concern in some countries, where dictators have used it to oppress minorities or political opponents.

The main functions of law are to (1) keep the peace, (2) maintain the status quo, (3) preserve individual rights and freedoms, (4) promote social justice, and (5) allow for orderly social change. Different legal systems meet these objectives differently. For example, a democratic regime might have a rule that everyone has a right to a fair trial and the privacy of their home, while a theocracy might restrict these rights.

Each nation-state has its own legal landscape, and the way it is governed varies considerably from place to place. A nation’s wealth, population size and political power determine how much of a role it plays in the world. The extent to which a government’s legal authority is respected is a crucial factor in whether it is considered legitimate. Revolts against existing political-legal authorities are a recurring feature of human history, and many states have experienced periods of civil unrest.

Law covers a very wide area of human activity, and there are numerous branches of it. Contract law regulates agreements that exchange goods or services; intellectual property law relates to the ownership of ideas, such as copyright or patents; property law outlines people’s rights and duties toward tangible things, such as houses and cars, and intangible assets such as bank accounts and shares of stock; trust law explains how to manage money — particularly pension funds — for retirement; and tort law helps people claim compensation when they have been injured or their belongings have been damaged.

Some laws are made by a group of legislators, resulting in statutes; by an executive, resulting in decrees and regulations; or by judges, resulting in the law of precedent, under which decisions of higher courts bind lower courts in future cases. Private individuals also create legally binding contracts, which can include arbitration agreements that adopt alternative ways of resolving disputes to standard court litigation. A professional who studies and argues the rules of law is called an attorney or a jurist. In the United States, they are usually referred to as lawyers; in the UK, they are commonly called solicitors or barristers. Some attorneys specialise in transactional work, such as writing contracts; others practise as litigators, arguing cases in court.