The World Wide Web Consortium

and Standards

C. M. Sperberg-McQueen,
Co-chair, W3C XML Schema Working Group
Co-chair, W3C XML Coordination Group
Domain Lead, W3C Architecture Domain

ACH/ALLC 2001

New York University, 14 June 2001

1. Overview

2. Who is the W3C?

The World Wide Web Consortium is a member-supported organization which creates Web standards.
Our mission:
to lead the Web to its full potential.

3. W3C goals and operating principles

4. Organization of work in W3C

Domains and Activities:
  • Architecture Domain
  • Technology and Society Domain
  • User Interface Domain
  • Web Accessibility Initiative

5. Architecture Domain

6. Technology and Society Domain

7. User Interface Domain

8. Web Accessibility Initiative

9. Goals of XML

The original goals of the XML activity were:
  • make SGML usable on the Web
  • add structure to Web documents
  • be simple (25 pp.), clean (validity)

10. Goals of XML

XML has grown beyond its original goals:
  • make SGML and HyTime, and DSSSL usable on the Web
  • add structure to Web documents and data
  • allow arbitrary data to be exposed on Web in XML
  • make XML usable in specific applications:
    • improve metalanguage for defining languages
    • query
    • authenticate with digital signature
    • canonicalize so signatures are more robust

11. Organization of XML work in W3C

12. Organization of XML work in W3C

13. Progression of W3C Specifications

14. Progression of W3C Specifications

15. XML Core WG

Chairs: Paul Grosso, Arnaud Le Hors
Specifications:
  • XML 1.0 Second Edition, ed. Eve Maler (XML 1.02e) (Recommendation)
  • XML Information Set (Candidate Rec)
  • XML Inclusions (XInclude) (WD in Last Call)
Pending:
  • XML Namespaces 1.1
  • Classification of XML Processors

16. XML Linking

Chair: Daniel Veillard
Two Proposed Recommendations:
  • XLink (standoff links, multi-ended links, better role labeling)
  • XML Base (dealing with relative URIs)
One draft in Last Call:
  • XPointer (addressing into XML)
Crucial contributions from Steve DeRose.

17. XML Schema

Chairs: Dave Hollander, Michael Sperberg-McQueen
XML Schema, parts 0, 1, and 2 a W3C Recommendation.
Pending:
  • entities/special characters problem
  • formal description of XML Schema
  • preparation of test suite

18. XML Schema Highlights

Like DTDs, but:
  • in XML, not in an ad hoc notation
  • coherent account of schema validation across multiple namespaces
  • full validation, partial validation (black boxes, white boxes)
  • simple datatypes
  • inheritance

19. XML Query

Chair: Paul Cotton
Five documents, most recently republished 11 June:
  • XQuery 1.0 and XPath 2.0 Data Model
  • XML Query Use Cases
  • XQuery 1.0 Formal Semantics
  • XQuery 1.0: An XML Query Language
  • XML Syntax for XQuery 1.0 (XQueryX)

20. DOM

Chair: Philippe Le Hégaret
Recommendations: Document Object Model (DOM) Level 2
  • Core
  • Views
  • Events
  • Style
  • Traversal and Range
Working drafts:
  • Level 2 HTML DOM
  • Level 3 Core
  • Level 3 Views and Formatting
  • Level 3 Abstract Schemas and Load and Save
  • Level 3 Events

21. DOM Highlights

DOM provides
  • an intelligent API for document manipulation
  • browser-independence* of scripting code
  • crucial tool for power users and system integrators (this means you)
  • support for editors ...

22. XML Protocols

Chair: David Fallside
Goal: create a simple foundation for program to program communication using XML.
Current work:
  • surveying existing work in the field (XML-RPC, SOAP, WDDX, XMI, Jabber, ebXML, ...)
  • working on requirements document

23. XSL

Chairs: Sharon Adler, Steve Zilles
XSLT a W3C Recommendation since November 1999
XSL (aka XSL FO) now a Candidate Recommendation
Work underway for XPath, XSLT maintenance (extensibility, types)

24. XSL Highlights

XSL has enormous importance for:
  • better layout
  • XML-to-XML transformations
  • systematic analysis and discussion of typographic organization, mise en page

25. SVG

Chair: Chris Lilley
Scalable Vector Graphics is a vector-graphic format for the Web. SVG is an XML tag set.
Current status: SVG 1.0 is a Candidate Recommendation.

26. Synchronized Multimedia WG

Chair: Aaron Cohen
Synchronized Multimedia Integration Language (SMIL) 2.0 now a Proposed Recommendation.
SMIL Animation a working draft

27. Semantic Web

The Semantic Web Activity includes
  • continuing work on RDF (Resource Description Framework), headed by Eric Miller
  • advanced development (software) led by Ralph Swick

28. RDF Core WG

Chairs: Dan Brickley, Brian McBride
Resource Description Framework: a low-level model for semantic structures.
Basic model: labeled directed graph.
Current work:
  • RDF Model and Syntax (Rec)
  • RDF Schema (Candidate Rec)

29. RDF — the basics

To describe a resource, you need a vocabulary in which to describe it.
The problem is that in a world-wide Web with universal access, we cannot rationally assume that we know in advance everything anyone might wish to say.
No closed-world assumptions!

30. RDF — the basics

To describe a resource, you need a vocabulary in which to describe it.
The problem is that in a world-wide Web with universal access, we cannot rationally assume that we know in advance everything anyone might wish to say.
No closed-world assumptions!
So — define a vocabulary ...

31. RDF — the basics

To describe a resource, you need a vocabulary in which to describe it.
The problem is that in a world-wide Web with universal access, we cannot rationally assume that we know in advance everything anyone might wish to say.
No closed-world assumptions!
So — define a vocabulary ... but also specify a more fundamental extensible semantic system in which it is defined.

32. RDF — the minimum

To say something about something is to describe some property/ies of your subject. You need at least:
  • a way to name the subject (URI)
  • a way to identify the property you are giving (label, property name)
  • a way to give the value of a property (literal, or URI)

33. RDF — a loose example

title("http://www.tei-c.org/P3",
      "Guidelines for Electronic Text Encoding and Interchange").
author("http://www.tei-c.org/P3",
      "Association for Computers and the Humanities").
author("http://www.tei-c.org/P3",
      "Association for Literary and Linguistic Computing").
author("http://www.tei-c.org/P3",
      "Association for Computational Linguistics").
editor("http://www.tei-c.org/P3",
       "C. M. Sperberg-McQueen").
editor("http://www.tei-c.org/P3",
       "Lou Burnard").
publication-date("http://www.tei-c.org/P3",
      "1994").

34. RDF — more loose example

title("http://www.tei-c.org/P3",
      "Guidelines for Electronic Text Encoding and Interchange").
author("http://www.tei-c.org/P3",
      "http://www.ach.org").
author("http://www.tei-c.org/P3",
      "http://www.allc.org").

35. Topic Maps

Topic Maps: an ISO (not W3C) work item:
  • standoff indexing
  • relations among entries
  • current work on XML Topic Maps (XTM)

36. RDF and Topic Maps

  • There's not much there: don't oversell, don't overbuy.
  • Alignment is crucial; users can help.
  • Vocabularies — markup languages, tag sets — are where the rubber meets the road.

37. Information

For current information: