Law is a system of rules that are enforced through social institutions to govern behaviour. Laws can be made by legislatures through legislation, the executive through decrees and regulations, or judges through binding precedent. Private individuals can create legally binding contracts, including arbitration agreements that may elect to accept alternative arbitration to the normal court process. The formation of laws themselves may be influenced by a constitution and the rights encoded therein. The law shapes politics, economics, and society in various ways and serves as a mediator of relations between people. A general distinction can be made between civil law jurisdictions, in which the legislature or other central body codifies and consolidates their laws, and common law systems, where judge-made precedent is accepted as binding law. Historically, religious laws played a significant role even in settling of secular matters, which is still the case in some religious communities, particularly Jewish, and some countries, particularly Islamic. Islamic Sharia law is the world's most widely used religious law.