Some Tools

(Graphical) Editors

eg, IsaViz (Xerox Research/W3C), RDFAuthor (Univ. of Bristol), Protege 2000 (Stanford Univ.)

eg, IsaViz (Xerox Research/W3C), RDFAuthor (Univ. of Bristol),

Protege 2000 (Stanford Univ.)

RDF Environments (interpreters, etc)

Jena (for Java, includes OWL Lite reasoning), RDFLib (for Python)

Redland (in C, with interfaces to Tcl, Java, PHP, Perl, …)

Kowari (OWL aware layer on top of Jena, coming)

Sesame (RDF Schema based repository and querying facility)

Validators

for RDF: http://www.w3.org/RDF/Validator/

for OWL: http://owl.bbn.com/validator/ (in development)

Ontology converter (to OWL)

at http://www.mindswap.org/2002/owl.html

Look at the W3C pages for updated information!