Technologies for the Near Future

RDF

Read about the W3C's RDF Activity at the W3C Web site

What is it?

The Resource Description Framework is the W3C's new technology for metadata, which is data about other data. It extends the functions that were introduced with PICS, of making statements about things on the Web that can be interpreted automaticaly by machines.

How does it work?

RDF statements are written in XML, encoding a statement of the type X has relationship Y to Z. The W3C Recommendation for RDF model and syntax defines two equivalent methods of expressing RDF. Because this is designed to be produced and consumed by software rather than people, the syntax may seem a little like magic- it consists of URIs and little bits of glue code. But the strength is that by describing things in terms of URIs it is possible to have each part of an assertion as a first class object, about which further assertions can be made.

Who is using it?

Machines and software. RDF is used to provide sophisticated control over access to W3C pages, in engines for searching the web, in classifying information for cataloguing systems. RDF is also used to build databases that are distributed over the Web.

Where is it going?

Experimental uses of RDF include

• adding it to SVG images to describe relationships between parts of a diagram, so the diagram can be presented in a different manner by software (an alternative understanding is that some SVG can be added to some RDF to represent it graphically...)
• describing privacy policies and accceptable use of user's private information, in P3P (the Platform for Privacy Preferences Project)

This page was produced by Charles McCathieNevile of W3C as part of a presentation for online@RMIT. All responsibility for errors rests with the author.