Creating RDF Schemas

So far, the property elements you use in RDF are up to you to define, unless you use someone else's RDF content model, such as the Dublin Core. Until recently, there was no real way to make sure that RDF software would be capable of checking the syntax of your RDF extensions.

However, the W3C has been working hard on creating an RDF schema language, and you can find the details at http://www.w3.org/TR/rdf-schema. It's not finalized yet (the specification is a candidate recommendation at this writing) and is not supported by any software, but when available, it will let RDF parsers check the full syntax of the extensions you make to RDF.

The Dublin Core Metatdata Initiative is solidly behind the idea of creating schemas to let RDF software check the syntax of RDF documents; you can read the group's thoughts on the matter at http://purl.org/DC/schemas/index.htm. Here's a partial extract from that page:

The diversity of metadata needs on the Web requires an infrastructure that supports the coexistence of complementary, independently maintained metadata packages. The World Wide Web Consortium (W3C) has begun implementing an architecture for metadata for the Web. The Resource Description Framework, or RDF, is designed to support the many different metadata needs of vendors and information providers. The Dublin Core Metadata Initiative expects to support the infrastructure for registries provided by RDF Schemas. Developments in this area will be reflected on these pages as they develop.