Law is a system of rules that people must follow to keep society safe and fair. It usually involves the police or courts and can include punishments like fines, jail sentences and deportation (removal from the country). Professionals who advise people about the law and represent them in court are called lawyers or jurists. They can specialise in different areas of the law, such as criminal law, civil law or family law.
Having good laws is very important for a nation, as they can protect individuals and ensure that everyone is treated equally. They can also stop people from oppressing minorities, for example, and help with the orderly transition of power between leaders. Many nations have a constitution, written or tacit, which sets out the main principles of their law.
The earliest legal systems were based on oral traditions and customs, but nowadays, most countries have laws that are written down and voted on by politicians in groups known as legislatures, parliaments or congresses, who are elected by the people they govern. The legislatures may write laws to set out the overall framework of the nation, and other laws to cover specific issues in more detail.
Many laws are created by governments to prevent crime and punish people who break the law, but in some cases they may make the law to encourage certain behaviour or to protect their environment. These types of laws are often influenced by cultural values, religion and ancient books that people read such as the Bible or the Vedas.
Other laws are created to provide protection for people who create art, music or literature by a kind of law called copyright. Another type of law protects inventions by a law called patent. A third kind of law, which is business-related, helps people with the names they choose for their companies and their distinctive logos by a law called trademark. Finally, some kinds of law, such as property and tort laws, help people with claims for compensation when they are harmed or have their property stolen.
Most countries have a system of courts to decide whether or not someone is guilty of breaking the law, and higher courts can remove laws that are seen as unfair. The laws of different countries are sometimes influenced by international law, which is the rules of the United Nations and other organisations that deal with global issues, such as trade or military action. In common law countries, decisions made by higher courts are binding and must be followed by lower courts, a principle known as stare decisis. In other countries with civil law, decisions by higher courts are not binding and lower courts can make their own rulings.