It appears to only extract structured data from Wikipedia, not natural language, so it is kind of basic then.
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DBpedia is a project aimed at extracting structured content from the information created in Wikipedia and making it available on the web in a machine-readable format. By converting Wikipedia's unstructured content into a structured format, DBpedia enables users to query the information using standard semantic web technologies, such as RDF (Resource Description Framework) and SPARQL (an RDF query language).