Semantic Web Tools and Toolkits

Implementation reports for the RDFCore Working Group and Implementation reports for Web Ontology Working Group are being prepared in preparation for W3C Proposed Recommendation status

A large number of open source tools and toolkits have been developed (Parsers, Reasoners, APIs, etc.)

In various languages (Java, Lisp, Python, PHP, Perl, C, C#, etc.)

Personal favorites I use on a weekly (daily) basis - Jena2 (java) and RDFlib (python)