Law is the set of rules that control a society or community. These rules are enforced through a system of penalties or punishments. They can be imposed by a collective legislature, resulting in statutes, by the executive through decrees and regulations, or they can be established by judges, as in common law jurisdictions. Laws can also be created by private individuals as legally binding contracts. Laws have a number of important purposes, including establishing standards, maintaining order, resolving disputes and protecting freedoms and rights.
Although legal systems vary greatly from nation to nation, they generally share some similarities based on historically accepted principles of justice. The most commonly encountered types of laws include common law, civil law, religious law and customary law.
Many of the most familiar concepts in law are derived from common sense or the scientific method. For example, the law of gravity states that objects that are in contact, such as an apple and the Earth, will fall together.
Other concepts are more specific to the practice of law. For example, the term arraignment refers to a court proceeding in which an accused person is brought before the judge and told what charges are being laid against him or her. The term attorney refers to a person who is trained in the law and practices it, and is sometimes used as an honorific, such as Esquire or Doctor of Law. Similarly, the term pro se means “on one’s own behalf” and refers to people who represent themselves in court without an attorney.