Dan Brickley's rdfs:seeAlso RDF linking
by Bob DuCharme
At XML 2003 in Philadelphia last week, Norm Walsh hosted a Town Hall discussion Thursday night on Practical Uses of RDF. Dan Brickley showed some slides that demonstrated how the RDF Schema seeAlso property can add linking to RDF data, particularly FOAF files, to make it easier for crawlers to find connections between them.
At first I was a bit confused: so much of RDF is about pointing to URLs; what makes rdfs:seeAlso special? Of course, the answer was in its documentation: it's "used to indicate a resource that might provide additional information about the subject resource." So it does have a fairly specific purpose, but one with a wide range of applications.
Note in particular the ninth of Dan's 11 slides, which demonstrates how to assign a type to the link destination. Like any link typing or link destination typing, this adds value to the link by letting human or automated agents decide whether traversing the link will give them information they want without requiring them to follow the link.
Of course, as long as you're using RDF, assigning a type to the link itself (as opposed to the link destination) wouldn't be too difficult, either. I'm confident that RDF will provide a fertile source of improvements to the world of linking technology.
What else can RDF offer to the world of linking?