7.3 Rule Languages

	The Rule Markup Language (RuleML) Initiative focused on an XML-based markup language for various types of rules (such as business, transformational, or reactive).
	SWRL became a W3C Member Submission in 2004, combining work from the DARPA Agent Markup Language (DAML) program and RuleML.
	Description Logic Programs (DLPs), as presented at the WWW 2003 conference, detailed the combination of description logics (OWL DL) and logic programs (RuleML) as a potential area of growth.
	The Web Rule Language (WRL) was submitted to the W3C in late 2005.
	Semantic Web Services Language (SWSL) Rules came out the same year, also part of a joint DAML/EU effort.
	Most recently, the RIF Working Group has been working toward a different goal, looking for rule interoperability using implementable specifications.
	The de facto standard language for Semantic Web rules is SWRL. SWRL enjoys strong community recognition and tool support, has a large user base.