From Seo Wiki - Search Engine Optimization and Programming Languages
Swoogle is a search engine for Semantic Web ontologies, documents, terms and data published on the Web. Swoogle employs a system of crawlers to discover RDF documents and HTML documents with embedded RDF content. Swoogle reasons about these documents and their constituent parts (e.g., terms and triples) and records and indexes meaningful metadata about them in its database.
Swoogle provides services to human users through a browser interface and to software agents via RESTful web services. Several techniques are used to rank query results inspired by the PageRank algorithm developed at Google but adapted to the semantics and use patterns found in semantic web documents.
Swoogle was developed at and is hosted by the University of Maryland, Baltimore County (UMBC) with funding from the US DARPA and National Science Foundation agencies. It is PhD thesis work of Li Ding advised by Professor Tim Finin
Ding, Li; Tim Finin, Anupam Joshi, Rong Pan, R. Scott Cost, Yun Peng, Pavan Reddivari, Vishal C Doshi, and Joel Sachs (2004). "Swoogle: A Search and Metadata Engine for the Semantic Web". Proceedings of the Thirteenth ACM Conference on Information and Knowledge Management (CIKM). ACM. pp. 652 - 659. doi:http://doi.acm.org/10.1145/1031171.1031289. http://ebiquity.umbc.edu/paper/html/id/183/.