Krextor is the KWARC RDF Extractor. It is an extensible XSLT-based framework for extracting RDF from XML, supporting multiple input languages as well as multiple output RDF notations. Krextor provides convenience templates that try to do “the right thing”™ in many common cases, as to reduce the need for manually writing repetitive code.

Krextor comes with extraction modules for OMDoc and OpenMath content dictionaries.

The extracted RDF graph will in most cases be an outline of the semantic
structure of an XML document, abstracting from the concrete syntax. It can be used for more easily exchanging or interlinking knowledge contained in XML documents on the semantic web. There are many tools that support querying RDF, using languages like SPARQL. If the extracted RDF is backed by an expressive ontology, a reasoner can be used to infer additional knowledge from it.