- From: Pierre-Antoine CHAMPIN <champin@cpe.fr>
- Date: Fri, 12 Nov 1999 10:44:16 +0000
- To: www-rdf-interest@w3.org
Ken Laskey wrote: > >My understanding is the an RDF schema is a specification for data (like a > >database schema) while an XML schema is specification for a language syntax. > >The two things are similar but distinct. I much agree with that, except that RDF schema is originally a specification for META-data > Here is another opinion of the relationship. Imagine an XML Schema > that defines the "hard" metadata for a book, e.g. author, title, > ISBN. These are immutable properties of the book. Now, the New York > Times does a review of the book which creates "assertions" which are > not hard facts but still related information. The connection of > these assertions to the book would be through RDF. RDF might also be > used by various booksellers to make assertions about the price they > are individually charging or possibly special offers about the book. There is something much more primitive about it : not everything is written in XML - at least not yet ;P ... So RDF is useful to describe metadata about GIFs, JPGs, or any XML document you can't modify... Another problem is that wether or not you can modify it, a resource often contains metadata about itself, in its own format. So it's been natural, when writing DTDs or XML-schemas, to include TAGs for describing metadata (author, ISBN, etc.) And those metadata are 'hard' in the sense that they are the most trustable, since they are written by the author herself ! Now that we have RDF, when we intend to include metadata in our documents (or elsewhere!) it looks reasonnable to use RDF rather than reinvent a metadata language. Pierre-Antoine
Received on Friday, 12 November 1999 05:24:32 UTC