Tools for Ontology and Semantics\\ #

• Reasoner: It is a system for computing (logical) consequences from a given knowledge base (source). A list of many reasoners, some of which are widely used, can be found here.
  
• RDF Store: An RDF store (or triple store) is a system for storing and managing RDF data (source). Some widely used RDF Stores are the following: BigData, Jena Toolkit, Sesame, Virtuoso, OWLIM, and AllegroGraph.
  
• Ontology Engineering Tool: Any tool used for creating ontologies or similar semantic documents (source). Some widely known ontology engineering tools are: Protégé and Semantic MediaWiki.
  
• Semantic Web Development toolkit: It is a set of functions or algorithms used for developing Semantic Web applications (source). Some indicative tools of this type are the following: Virtuoso, Jena Toolkit, Callimachus, ActiveRDF, and Redland.
  
• Semantic search tool: It is a system for searching semantic information, or for searching content based on semantic data (source).
  
• Semantic content management system: It is a system for managing (editing, organising, delivering, etc.) semantic data of some form (source). Some representative systems are the following: Semantic MediaWiki, KnowWE, and SMW+. 
  
• Semantic Browser: Any tool used for browsing semantic content, or for browsing content based on semantic data (source). Some indicative tools of this type are the following: Callimachus, Anzo, RelFinder, OpenLink Data Explorer, and Tabulator.
  
• RDF Indexing Service: It is a service (Web-based or not) for indexing useful information from RDF documents (source). Some indicative services are the following: Sindice, Swoogle, and Linked Media Framework.
  
• Semantic Conversion Tools: Semantic Web tools able to convert data (e.g., relational, semi-structured) to RDF-based formats (source). A special sub-type of this tool type maps to  RDB2RDF Conversion Tools which are able to transform relational data to RDF ones. Indicative tools for the main type are the following: Semantic Java, Anzo, PoolParty Extractor, VirtuosoRDFViews, and Krextor. Indicative tools for the sub-type can be found here.
  
• Semantic Agent System: It is a semantically enabled multi-agent system (source). Some examples of such systems are the following: RuleResponder and SEAGENT Platform.