The last day of WWW10 was given over to Developer’s Day, which offered the
chance for developers working on web technologies to share and discuss details
of their projects. I attended the Semantic Web day, where in the morning
several W3C Team members showcased href="http://www.w3.org/2001/Annotea/">Annotea, their tool for annotating
web pages.

Annotation isn’t new, and there have been several attempts at it so far on
the web. One of these was the controversial (and now defunct) href="http://www.thirdvoice.com/">Third Voice, allowing post-it note style
adornment (some might say defacement) of pages. Annotea takes a slightly
different approach, being non-proprietary and based on open web standards.

Annotea is basically an annotation server: it uses an RDF database and a
simple HTTP front end to store annotations, and respond to annotation queries.
The W3C has deployed an Annotea server at href="http://annotest.w3.org/">http://annotest.w3.org/, but anybody is
free to deploy one — so you can have multiple sources of annotation.

In order to view or add annotations, you need a user agent which supports
them. Amaya, the W3C browser/editor, has pretty sophisticated support for
annotations, and is a good place to start experimenting.

Work is in progress to make other tools understand how to manipulate these
annotations. As well as a href="http://www.w3.org/2000/02/collaboration/annotation/JavaScript/Annotea-JavaScript.html">servlet/JavaScript
interface, there’s the href="http://annozilla.mozdev.org/">Annozilla project, which adds a
sidebar to the Mozilla browser to display annotations.

Taking a look under the hood, Annotea is quite simple to understand. It
uses an RDF schema to
define the properties of an annotation, and is reasonably easy to read and
figure out what’s
going on. A fun and relatively simple experiment might be to get a weblog
or comment-system to export its content in Annotea format, and therefore show
up in annotation-aware user agents.

Annotea is designed so you there can be any number of annotation servers.
This recognizes the decentralized nature of the web, and means you can switch
in annotations from your trusted sources, or for instance, in a corporate
setting, ensure your annotations get no further than your own intranet.

A burning question among pro-standards attendees at the 10th International
World Wide Web conference in Hong Kong last week was how to get browser and
editing tool vendors to implement XHTML.

XHTML is the latest incarnation of HTML. It uses an XML format, and
enforces a higher degree of strictness than HTML does — XHTML documents are
either right or wrong, there’s no halfway house where the browser tries to
recover. If you make an error, you have to fix it!

As with many web standards though, the speed of implementation in browsers
and editors is likely to be disappointingly slow, so what can users and
standards-makers do to encourage its uptake? Participants in the W3C “Town
Hall” meeting discussed just this. For XML geeks, the advantages are obvious
– having XHTML web pages allows them to use tools like XSLT and other
XML-specific technologies to process the pages.

For web designers, XHTML is advantageous because it’s an indisputable
standard — write valid XHTML and you’re more likely to get the same result in
each browser that implements it, as there’s nothing browser-specific about any
of the elements in XHTML.

However, neither of those are necessarily a compelling reason for the
average user, who happily surfs around unaware that web designers have had to
jump through hoops to get the pages looking right. During discussions in the
meeting, though, one advantage came up that would benefit both vendors and
users: processing XHTML is simply much faster than processing HTML.

As XHTML is strict, the browser doesn’t have to waste time doing a “best
guess” as to what the page should look like: the page is either correct, or it
isn’t. What’s more, it doesn’t take much to add this feature to browsers — if
a page’s DOCTYPE is XHTML, then switch in the new, fast, XHTML parser, if not,
use the existing code you have already. Unfortunately, browser vendor
Microsoft was utterly noncommital about their plans to implement XHTML. Dave
Massey from Microsoft commented that they are “investigating” XHTML, and may
add it to their browser, but he couldn’t say if or when.

Once again it seems that it must rest with the users to campaign for
standards compliance from vendors: so they can get fast-loading, predictable
web pages. Microsoft always say that they implement according to users’
priorities, so grassroots action seems like a potential route forward.
However, with millions of users, it seems that they’re likely to listen to the
big spenders first — what voice do average web users and developers have?

While business-oriented XML applications have been grabbing the tech media
spotlight, exciting work has been in progress in the world of Web
multimedia.

Presenting on the user interface work of the W3C at the 10th International
World Wide Web Conference in Hong Kong, Thierry Michel gave the audience the
latest news on SMIL (pronounced “smile”). The Synchronized Multimedia
Integration Language allows the co-ordination of multimedia elements in a
presentation, and is an XML language. href="http://www.w3.org/TR/REC-smil">SMIL 1.0 has been around for a while
now, and is implemented in programs like RealPlayer.

SMIL allows items to be layed out not just over the page, but also over
time. It also allows alternative presentation depending on language or
available bandwidth, and accessibility features such as captioning and ALT
tags are supported. There are currently around ten SMIL browsers
available.

Michel explained what the next generation of SMIL, SMIL 2.0, had in store.
The most significant change is the splitting of SMIL into modules. This allows
various components of the language to be re-used in other contexts. As well as
the modules, there are now three profiles defined, including a
“basic” flavor for lightweight devices, and an XHTML-SMIL flavour for use in
browsers.

The splitting up of SMIL allows implementations, such as in Internet
Explorer 5.5, where the timing and animation from SMIL can be applied within,
and to, XHTML documents. Michel
demonstrated some impressive functionality running in IE5.5. In addition to
modules and profiles, SMIL 2.0 will bring new visual transition and animation
effects, and increase support for internationalization and accessibility.

The SMIL Working Group expect SMIL 2.0 to reach the final stage of its
development, W3C Recommendation, during Summer 2001. The final recommendation
will ship with a set of test cases for implementors.

Following Thierry Michel, Chris Lilley presented on the progress of the
W3C’s Scalable Vector Graphics format, href="http://www.w3.org/Graphics/SVG/">SVG. SVG represents images in their
component, vector, form as opposed to as raster graphics, such as JPEG or PNG.
As a result, graphic items can be both smaller in file size and vastly
superior in rendering quality.

SVG has been a long time in its development, and during that time has
acquired several good implementations, the most popular being Adobe’s browser
plugin. SVG 1.0 will soon reach Recommendation stage, and there is already
much interest in the next version of the specification. Features likely to be
in that new version include more support for small devices, not just PDAs but
also smaller devices like cell phones, and the integration of SVG with other
XML user interface languages such as href="http://www.w3.org/Math/">MathML and href="http://www.w3.org/MarkUp/Forms/">XForms.

Opening the tenth International World Wide Web Conference in Hong Kong
Wednesday, Tim Berners-Lee told the attendees they could congratulate
themselves for the progress made so far on the Web, but that they weren’t
finished building yet.

Announcing the release of a landmark XML specification, W3C XML Schema,
Berners-Lee explained that the three specifications — XML 1.0, XML Namespaces
and XML Schema — formed the new foundation of XML. XML Schema allows the
description in XML itself of XML languages, such as SVG or XHTML, and is
designed to replace DTDs, which served the same purpose in XML 1.0.

The development of the XML Schema specification has been characterized by
controversy and criticism, since the early concerns in late 1999 as to whether
Microsoft would support the spec. Berners-Lee praised the Schema working group
for their perseverance in difficult circumstances. Though many in the XML
developer community still hold reservations about the specification, most
agree that XML Schema will, indeed has to, succeed.

So now, over three years since the XML 1.0 Recommendation was first
published, the W3C have built a foundation for XML applications that its
member companies think can be used in today’s applications. However, there’s
more to the total XML architecture than the foundation. Berners-Lee noted that
a key technology, the XML Query language, a kind of SQL for XML data, is still
in development, as are XLink and XPointer, XML technologies for linking
documents together.

There was a glimmer of encouragement for those who feel that XML has got
out of hand in its complexity, Berners-Lee saying that there was a need for
revisiting and simplifying the existing XML architecture. He said that a W3C
Recommendation was not the end for a specification, and that taking another
look at technologies was required in reaction to implementation experience and
questions of interpretation.

Berners-Lee then went into detail on his plans for the next stage in the
Web, the so-called Semantic Web, recalling the early days of the web in 1990
– the “fun stage.” The Semantic Web initiative is aimed at making the Web
machine-readable, by creating interoperable formats for information. It is
currently seen mostly as a vision for the future, perhaps in a similar way as
the Web itself was originally perceived ten years ago. However, Berners-Lee
was not perturbed that industry was not embracing the Semantic Web at the
moment, preferring that it attracts the attention of developers who will help
build it.

Certainly, the Semantic Web is attracting more interest at this conference
than at last year’s WWW9 conference, an afternoon Semantic Web session packing
a room full of over 350 attendees. However, the W3C still has some way to go
in communicating their vision, as many participants were still left scratching
their heads afterwards. The Semantic Web is something that a lot of people are
attracted to, but find that the actual details elude them.