Law is a system of rules that regulates the conduct of people and their relationships with each other. It is enforced by a controlling authority through penalties such as fines or imprisonment. Law has a long history and many different ideas about it exist. In most countries today laws are written by group legislatures – parliaments or congresses – that are elected (chosen) by the people. In some countries, such as the United States, the laws are compiled from decisions made by judges in case trials, and this is known as common law. In other countries, such as Japan, the laws are based on a set of written codes that judges must follow in making decisions, and this is called civil law.
A person who studies and argues the laws is known as a lawyer, jurist or attorney. These professionals often specialize in certain areas of law, such as contract law or criminal law.
Laws are important because they set out the rules that people must obey. They also protect them from injustices by those in power. They ensure that core human and property rights are respected by all people, regardless of social class. Without them, people have no protection from tyrants and dictators who may take away their freedom or steal their possessions. Laws also provide a way for people to make complaints about the behaviour of governments, corporations or individuals. Competition law, for example, aims to prevent businesses from using their economic power to artificially drive up prices.