Wednesday, March 14, 2007
RDFa
W3C has released a primer for RDFa, a working draft specification for embedding RDF metadata in HTML or XHTML. The examples show how it can be used with <span> tags and attributes to mark up data in line, so it isn't necessary to enter the same information as readable text and again as metadata.
This sounds very useful, and I want to play with it on my book review pages to make bibliographic information extractable. Of course, to be particularly useful, there will have to be extraction software, and it will be developed only if enough sites use RDFa metadata to make it worthwhile. Probably spambots will be the first to take advantage of it, unfortunately.
There's an experimental extractor available here. It spits out Python errors when used on HTML that isn't well-formed, but some people have managed to use it.
XML.com has an introduction to RDFa.
