Lite, 149 were OWL DL and 337 OWL Full (by syntax). They found that 19 ontologies had in excess of 2,000 classes, and that 6 had more than 10,000. The same survey collected 587 RDFS vocabularies. In 2021 Prof. Ian Horrocks was awarded the Lovelace Medal in recognition of his work towards the standardization of OWL which is considered the leading reason for its widespread adoption. The result of this research and development was RDFox, a knowledge graph and reasoning engine. The significance of this lies in the cultural shift of the technology space, leaving behind the dismissive attitude towards reasoning technology's inability to perform at speed, as RDFox proved beyond a doubt that high-speed reasoning was not only possible, but commercially viable. Many institutions have now adopted this technology as a solution to social and industrial problems involving highly interconnected data. Ontologies The data described by an ontology in the OWL family is interpreted as a set of "individuals" and a set of "property assertions" which relate these individuals to each other. An ontology consists of a set of axioms which place constraints on sets of individuals (called "classes") and the types of relationships permitted between them. These axioms provide semantics by allowing systems to infer additional information based on the data explicitly provided. A full introduction to the expressive power of the OWL is provided in the W3C's OWL Guide. OWL ontologies can import other ontologies, adding information from the imported ontology to the current ontology. Example An ontology describing families might include axioms stating that a "hasMother" property is only present between two individuals when "hasParent" is also present, and that individuals of class "HasTypeOBlood" are never related via "hasParent" to members of the "HasTypeABBlood" class. If it is stated that the individual Harriet is related via "hasMother" to the individual Sue, and that Harriet is a member of the "HasTypeOBlood" class, then it can be inferred that Sue is not a member of "HasTypeABBlood". This is, however, only true if the concepts of "Parent" and "Mother" only mean biological parent or mother and not social parent or mother. Species OWL dialects The W3C-endorsed OWL specification includes the definition of three variants of OWL, with different levels of expressiveness. These are OWL Lite, OWL DL and OWL Full (ordered by increasing expressiveness). Each of these sublanguages is a syntactic extension of its simpler predecessor. The following set