Custom. In the central Islamic countries, it is the common name for unwritten customary law, in contrast to written Islamic law codes or other legal canons. Adat is a synonym used in other parts of the Islamic world, especially Indonesia. Urf often refers to three different types of legal categories: the way common people maintain order, engage in social interactions, or conduct business locally, for example, in the marketplace or in wedding ceremonies; the legal decisions made by a ruler and his representatives; and the practices of local courts. According to the Malikis and some Hanafis such as Ibn Abidin, urf is considered to be a source of law.
See also Adat