W3C Activities

W3C Activity: Hypertext Markup Language (HTML)

This is the W3C statement of direction concerning HTML. It is in the W3C activity list as part of the User Interface Domain.

HTML is a data format for exchanging documents on the Web. It provides interoperability between a number of products that cover a wide range of applications: word processing, collaborative authoring, data base publishing, interactive applications, and more.

There is perhaps no more controversial area in Web standards than HTML extensions.

W3C plays a vital role in the evolution of HTML by both stimulating development in critical directions and providing a forum where competing parties can meet to reach a consensus about new features.

Among the extensions currently under discussion are rich forms and interactive documents, the ability for pages to be changed dynamically via scripting, frames and subsidiary windows, improved access to HTML features for people with disabilities, multimedia objects, and mathematics. Richer representations for meta-data are being developed by W3C's DSIG working group.

Requirements

The web presents readers with a consistent view of a diverse, distributed set of information sources. HTML is a critical technology in making this possible. It should satisfy the needs of all applications where document interchange is essential, from hypertext electronic mail to data base publishing.

Richness

In order to support the common needs of information providers for publishing and delivering services over the Web, HTML, in combination with style sheets, must have rich expressive power and visual impact. These needs include everything from casual communication to technical documentation to entertainment, advertising, and marketing.

HTML must also provide a simple user interface for interactive applications, such as order forms and database queries.

Simplicity

At the same time, HTML must be simple. The simplicity of HTML has been critical to the widespread deployment of the web. HTML is simple enough that thousands of people learned to edit the markup by hand. That in itself may be a passing phenomenon. But that same simplicity allowed thousands of developers to make HTML interchange part of their systems: from desktop software to database integration to embedded systems and set-top boxes. And the ability of people to spot and correct errors contributes to the overall robustness of the web.

HTML should remain, as far as practical, backwards compatible with existing documents. Each new feature is evaluated carefully to understand how it interacts with the deployed base of software and documents, in order to provide smooth, continuous evolution of the web.

Accessibility and Platform-Independence

While many formats express documents strictly in terms of placement of marks on a page, the use of descriptive markup idioms such as paragraphs, heading, and lists allows HTML documents to be rendered effectively on a variety of platforms, and for a diverse audience. The capabilities and constraints of a variety of platforms contribute to the design of HTML:

Requirements concerning Access for People with Disabilities are the subject of a W3C activity of their own.

Products

In order to meet those requirements, we have identified a number of products, or deliverables. Specifications of the current version of the language is obviously one of them, but there are other deliverables that could help to reach a common understanding of all users and producers of HTML documents. Depending on available resources, not all of these deliverables will be developed by W3C, but all are desirable:

  1. A language specification, with its DTD and associated resources (entities, SGML declaration, and catalog file) for use in validation
  2. Recommendations for using style sheets with HTML
  3. Modular sample implementations for HTML user agents
  4. Testing and certification services, in order to promote reliability and fidelity of communications on the web
  5. Common API for access to, and dynamic manipulation of, HTML objects from scripts and other programs
  6. A full suite of documentation: introduction, quick reference, tutorials, style guides, training, test suite, etc.

HTML Features Under Consideration

In particular, we have identified that specifications addressing the following features are critical to meet the requirements above. The W3C HTML Working Group has produced a number of working drafts, which will be incorporated into future versions of the HTML specification:

Scripting
This covers the ability to add scripts that augment the capabilities of HTML and embedded objects. The work will cover the definition of a standard event model, together with the ability to include script commands within individual HTML elements, within a SCRIPT element in the document head or linked script files. The notation for scripts is decoupled from the HTML specification. See also: Web Browser Scripting Services
Forms and Interactive documents
Improvements to forms and interactive documents, in particular for accessibility by people with disabilities. The improvements over the HTML 2.0 specification include: control over tab order, active field labels, disabled and read-only form fields, grouping related fields into field sets and support for scripting.

The long term goal is to bring HTML-based forms up to par with contemporary database application development tools and to develop open specifications for transferring new kinds of interactive documents over the web.

Frames, Layout and Subsidiary Windows
HTML markup for frames is being adopted by information providers as a powerful enhancement to the web user interface. Initial implementations exposed the complexities introduced by this mechanism, and a number of approaches and extensions are being explored.

In the future, we expect designers will want different layout for the same document depending on the medium:

We are investigating CSS extensions to allow the same document to be presented using different layouts. See WD-style and WD-positioning. Further information can be found on the W3C Style Sheets activity page.

Mathematics
HTML currently lacks an effective means for embedding mathematical expressions. This work is aimed at providing an interoperable representation that can convey presentation and semantics for math. A proposal for an XML-based representation is under investigation, along with character sets and entities.
Hypertext Links in HTML
Link relationships and meta-information are an underutilized aspect of the web architecture which can be used to extend the expressive capability of web pages and increase the effectiveness of web communications.

For example, typed links can represent navigational and structural idioms such as tables of contents, indexes, and glossaries. In addition to enhanced browsing, this meta-information can be exploited by search services to increase the precision of searches and the relevance of the search results. Hard copy tools can exploit these structures to automate printing collections of pages.

Inserting Objects into HTML
A variety of competing approaches have been proposed for embedding objects into documents: IMG, FIG, EMBED, APP, and APPLET. This document presents a general solution for embedding objects of all sorts with rectangular outlines. These objects are not restricted to static images, but can be defined by mobile code or plug-in modules, that respond to a variety of different events.
Document Object Model
The Document Object Model Working Group is defining a platform and language neutral interface to allow programs and scripts to dynamically access and update the content, structure and style of documents. This will allow the document to be further processed and will enable incorporation of the results of that processing back into the presented page.

"Dynamic HTML" is a term used by some vendors to describe the combination of HTML, style sheets and scripts that allows documents to be animated. W3C has received several submissions from members companies on how the object model of HTML documents should be exposed to scripts. These submissions do not propose any new HTML tags or style sheet technology. The DOM-WG is working hard to make sure interoperable and scripting-language neutral solutions are agreed upon.

Implementation Experience: Amaya

Implementation experience is critical to the development of quality specifications. In addition to the experience of engineers in member organizations, the W3C staff develops and maintains Amaya, an editor/browser with support for style sheets. Its open-ended architecture is well suited to make experiments for new HTML features. See the Amaya Activity Statement for background and plans.

The W3C staff no longer maintains Arena, though the source code remains freely available.

Related Work

A number of other products critical to the overall success of the W3C HTML activity are covered in other activity statements:

Current Situation

We have made considerable progress toward the deliverables outlined above:

W3C HTML Working Group (formed in 1996)
The member organizations represented in the working group have publicly committed to producing comprehensive HTML specifications. This group has produced two important specifications by the end of 1996: CSS1 and HTML 3.2. The group was previously known as the HTML Editorial Review Board. In 1997, it was reformed into the W3C HTML Working Group. Note that portions of the group's work prior to 1997 are covered on the activity statement for style sheets.
HTML 3.2 becomes a W3C Recommendation (January 1997)
HTML 3.2 represents the collaboration, consensus, and commitment of support of the W3C HTML ERB participants on features such as tables, floating images, client-side image maps, and super/subscripts.

W3C plays a role in many stages of the development of HTML. We stimulate development in directions that we feel are critical to the evolution of the web by drafting proposals and prototyping new features. Meanwhile, new features also enter the market directly in beta releases and products.

The features then go through an experimental deployment phase. In many cases, the information providers find the features very valuable, and competition demands that they be supported. In other cases, the features aren't picked up by the information providers nor the other implementors. Once a number of vendors support the feature, it's appropriate for W3C to document it as a recommendation.

W3C plays a vital role in facilitating the consensus process, providing a neutral forum, as well as editing and engineering resources.

The work started by the HTML Working Group has been split into the form of a number of more focused working groups:

Next Steps

These groups are working on the next version of HTML (code named Cougar) and extensions to CSS. Just as HTML 3.2 consolidated a number of work items, we intend to collect a number of proposals which are currently under discussion.


If you have time and resources to contribute, contact <html@w3.org>.
Dave Raggett, Arnaud Le Hors, and Vincent Quint, W3C contacts for the HTML area
$Date: 1997/04/28 16:02:22 $