Thursday, September 4, 2008

RDFa is a Proposed Recommendation!

After ages of hard work, the W3C has finally promoted the XHTML+RDFa language definition and the processing rules for RDFa to Proposed Recommendation status. This document represents a substantial advance for people who want to annotate their web pages with semantic markup:
  • It is completely compatible with existing popular user agents.
  • There are lots of implementations out there already that support extracting semantics marked up via RDFa.
  • It is already in use by the Yahoo! SearchMonkey engine.
  • Popular user agent plugins such as Operator and Fuzzbot already understand it.
  • While the mechanism is not explicitly defined (yet) it is possible to use the same markup in HTML and XHTML pages and get the same semantics.
  • Unlike microformats, the idiom for annotating your content does not conflict with the normal semantics of (X)HTML (e.g., the class attribute, the title attribute, and abbr).
Why would you want to use RDFa? For the same reason you want to use microformats. Because you care about machines understanding what is on your page, not just humans.

For lots more information on how to start using RDFa right now, see the web site.

Wednesday, September 3, 2008

Why we do what we do...

An open letter to my standards making colleagues:

There are 4 classes of problems people like us work on solving:
  1. Yesterday problems. Also known as "fighting the last war". I don't think any of us want to work on semantic markup for yesterday. The W3C doesn't usually work on yesterday problems, except when updating an old recommendation to incorporate errata or something.
  2. Today problems. Problems that lots of people are still running into, and where a quick solution, even if it is "hacky", would have immediate benefit if it had wide support. WAI-ARIA could have been such a solution were it actually quick. Microformats are another good example. In general the W3C does not look at this type of problem because the processes are too long and frankly the market will deal with them before we ever could. However, I see XHTML Access and XHTML Role as fitting into this category. Should have been completed sooner, but whatever.
  3. Tomorrow problems. Problems that cutting edge people are running into now, and that lots of people are going to run into really soon. This is where the W3C should focus its energy, and certainly where we have been looking in the recent past. RDFa is a solution to a "tomorrow problem" in my mind. If we can quickly show how to map it to microformats, then it is also a solution to a today problem and will help the people using the solution also survive into tomorrow.
  4. Someday problems. Problems that visionaries have decided are where the industry is heading, and for which we need to start developing solutions now because it is going to take forever. This type of work has no place in the standards community. Instead, this is called "research" and there are appropriate places to do it. The W3C is not a good venue for cutting edge research.
HTML 4 is a today problem. Finding a way to help people with that problem interact with the semantic web seems like a major win. Microformats is a today problem in that it does not scale. Finding a way to bring them into the fold of RDFa seems like another major win. Doing both is a HUGE win.

XHTML / XML grammars and easy annotation is a today problem and a tomorrow problem. We need a quick bridge, and we need a long term solution. I think we have both in the XHTML RDFa module.

Improved accessibility is a today problem and a tomorrow problem. We have the start of some long term solutions with the Access and Role modules. These, coupled with dymanic semantics defined through RDF vocabularies are a great way to start making the web a more friendly place for people with disabilities.

Combining these technologies with WAI-ARIA into a new version of XHTML solves a today problem and a tomorrow problem. And, even better, it will work in existing user agents right now. We don't need to wait for the browser vendors to implement anything. That's surely the right place for us to be focusing our energies.

That's my opinion. That's what I am working toward. It might be a little head in the sand, but I sleep well at night and I am confident that we can declare victory very very soon. I invite you all to work with me on solving today and tomorrow problems. It's fun. It's rewarding. I doubt the people working on someday problems can say the same.