Swoogle
Swoogle , the semantic web search engine and metadata service provider, is a crawler-based indexing and retrieval system for Semantic Web Documents (SWDs), that is, web documents written in RDF or OWL.

Main Features of Swoogle
- Search semantic web ontologies and documents
- Searches SW terms i.e.; URIs
- Provides metadata of SWDs.
Architecture of Swoogle
Swoogle architecture can be broken into 4 major components such as SWD discovery, metadata creation, data analysis, and interface.

SWD Discovery:- At the back end, the SWD Discovery creates a database of SWD’s using a hybrid approach to harvest the semantic web.
Indexing:- This component indexes SWDs using its metadata and for this, it captures encoding schemes and it records ontology properties such as label, comment, relations between two SWDs via imports, extend, etc.
Analysis:- This component uses the created metadata to derive analytical reports such as classification of SWOs and SWDB, ranking SWDs using rational surfer model.
Services:- This interface component focuses on providing data services such as search services that search ontologies at the term level.