World Wide Web Consortium Issues Authoring Tool Accessibility Guidelines as a Recommendation

Author(s) and publish date

Published:: 3 February 2000

New Guidelines Spur Development of Tools that Help Produce Accessible Web Content

http://www.w3.org/ -- 3 February 2000 -- The World Wide Web Consortium (W3C) today announced the release of the "Authoring Tool Accessibility Guidelines 1.0" (ATAG 1.0) specification, providing guidance to developers on how to design accessible authoring tools that produce accessible Web content. As a W3C Recommendation, the specification is stable, contributes to the universality of the Web, and has been reviewed by the W3C Membership. W3C encourages developers to promote Web accessibility by implementing this Recommendation.

ATAG 1.0 Provides Guidance for Tool Developers

The Authoring Tool Accessibility Guidelines 1.0 explain how developers of authoring tools, such as HTML editors and site management tools, can encourage and assist in the production of accessible Web content through prompts, alerts, checking, repair functions, and help files in their tools. In addition to their value to accessibility, many of the principles addressed in the specification, such as the importance of producing and preserving valid markup, promote interoperability of the Web in general.

The Guidelines address not only the accessibility of content produced by tools, but the accessibility of the tool itself. The Web is not a read-only medium, and accessible authoring tools will enable all people to publish to the Web, regardless of disability.

ATAG 1.0 Will Contribute to Increase in Accessible Web Content

There has been an increasing interest in creating accessible Web sites particularly since the May 1999 release of W3C's Web Content Accessibility Guidelines 1.0, and a correspondingly greater demand for tools that produce accessible content. Implementation of ATAG 1.0 will contribute to the proliferation of accessible Web content.

"Most content on the Web is created using authoring tools. If authoring tools seamlessly guide authors in creating accessible content, the wealth of information on the Web will become more accessible," said Jutta Treviranus, Chair of the Authoring Tool Accessibility Guidelines Working Group and Director of the Adaptive Technology Resource Centre at the University of Toronto. "Just as important, the Web as a means of expression should not be reserved for people without disabilities. These guidelines promote authoring tools that create content that is accessible, and authoring tools that are usable by people with disabilities, thereby cultivating a World Wide Web that we can all participate in."

ATAG 1.0 Addresses a Wide Array of Authoring Tools

The Authoring Tool Accessibility Guidelines 1.0 address a broad range of tools, including WYSIWYG editors, "save-as-HTML" conversion tools, tools that dynamically generate content from databases, formatting tools, image editors, and site management tools.

ATAG 1.0 consists of twenty-eight requirements, called "checkpoints," for developing accessible authoring tools that produce accessible content. The checkpoints are organized according to seven overriding design principles, called "guidelines."

As with the Web Content Accessibility Guidelines 1.0, ATAG 1.0 checkpoints have three priority levels, which correspond to their importance for accessibility. There is a checklist providing a quick overview of the checkpoints by priority. W3C has made icons available for products claiming any one of the three conformance levels.

Broad Support, Multiple Implementations Under Development

The ATAG 1.0 Recommendation was written by members of the Authoring Tool Accessibility Guidelines Working Group (AUWG), composed of key industry players as well as disability and research organizations. A list of AUWG members is available.

The Authoring Tool Accessibility Guidelines Working Group is preparing a variety of implementation support materials to assist developers, including the "Techniques for Authoring Tool Accessibility," published today as a W3C Note. At the time of this release, every requirement of the Guidelines has been implemented by one or more existing tools, though no tool yet satisfies all checkpoints. In addition, authoring tool developers are planning ATAG 1.0 support in upcoming products, indicated among the wide range of testimonials.

About the Web Accessibility Initiative

W3C's Web Accessibility Initiative (WAI), in partnership with organizations around the world, is pursuing accessibility of the Web through five activities:

ensuring that core technologies of the Web support accessibility;
developing guidelines for Web content, user agents, and authoring tools;
developing evaluation and repair tools for accessibility;
conducting education and outreach;
coordinating with research and development that can affect future accessibility of the Web.

The WAI International Program Office is supported in part by funding from the U.S. National Science Foundation, U.S. Department of Education's National Institute on Disability and Rehabilitation Research, European Commission's DG XIII Telematics Applications Programme for Disabled and Elderly, the Government of Canada, IBM, Lotus Development Corporation, Microsoft Corporation, and Bell Atlantic. For more information see http://www.w3.org/WAI.

About the World Wide Web Consortium [W3C]

The W3C was created to lead the Web to its full potential by developing common protocols that promote its evolution and ensure its interoperability. It is an international industry consortium jointly run by the MIT Laboratory for Computer Science (MIT LCS) in the USA, the National Institute for Research in Computer Science and Control (INRIA) in France and Keio University in Japan. Services provided by the Consortium include: a repository of information about the World Wide Web for developers and users, reference code implementations to embody and promote standards, and various prototype and sample applications to demonstrate use of new technology. To date, 390 organizations are Members of the Consortium. For more information see http://www.w3.org/

Contact America --: Janet Daly, <janet@w3.org>, +1.617.253.5884 or +1.617.253.2613
Contact Europe --: Carine Rigaud <cariner@fgcom.fr>, +33.1.41.18.85.55
Christelle Moraga <christellem@fgcom.fr>, +33.1.41.18.85.55
Contact Asia --: Yuko Watanabe <yuko@w3.org>, +81.466.49.1170

Testimonials for Authoring Tool Accessibility Guidelines Recommendation

American Association of People with Disabilities | Access to Information Task Force | Amaya | Bell Atlantic Corporation | The Boeing Corporation | Electricité de France | Hong Kong Blind Union | HTML Writers Guild | IBM | Internet Advisory Council, Government of Canada | Microsoft Corporation | Ministry of Science and Technology, Portugal | RealNetworks | Royal National Institute for the Blind | Sausage Software Limited | SID@R| SoftQuad Software || In French: Amaya (fr) | Electricité de France (fr) || In Spanish: SID@R (es)

People with disabilities have long been excluded from new technologies. A growing technology gap threatens to increase the high rates of unemployment and exclusion that people with disabilities face in the United States and worldwide. AAPD, the largest cross-disability membership organization in the U.S., enthusiastically welcomes these new guidelines which will help make the Web more accessible to the constituency we represent. AAPD encourages all Web site developers to demand authoring tools that implement these guidelines and that can be used to maximize the participation of all in the Web community.

-- Andrew J. Imparato, President and CEO, American Association of People with Disabilities

The Authoring Tool Accessibility Guidelines, together with W3C's Web Content Accessibility Guidelines issued last spring, represent a sea change for the Internet. If tools implementing these guidelines are placed in the hands of Web designers, accessibility will be the standard outcome of Web site development. By making the tools themselves accessible for individuals with disabilities, the opportunity to participate in the global community of the Internet is opened to all. The Access to Information Task Force applauds the work of WAI and pledges our efforts to promote use of these guidelines.

-- Paul W. Schroeder, Chair, Access to Information Task Force, which includes: The American Foundation for the Blind (AFB), The American Council of the Blind (ACB), The Association for Education and Rehabilitation of the Blind and Visually Impaired (AER), and the National Industries for the Blind (NIB).

The Authoring Tool Accessibility Guidelines represent a major step forward that will allow for the creation of accessible Web pages. W3C's Amaya team wholeheartedly supports these guidelines, and has already started implementing the guidelines in Amaya, W3C's Web browser/editor test bed. Implementing and demonstrating W3C Recommendations is the main purpose of Amaya, and implementing the Authoring Tool Accessibility Guidelines will be among the top priorities of the Amaya development team.

-- Irène Vatton, Amaya Architect, W3C/INRIA

As a company dedicated to accessible communications, Bell Atlantic would welcome the availability of commercial-grade authoring tools to automate the creation of accessible web sites. The incredible potential of the Internet will not be fully achieved unless all users -- including those with disabilities -- can successfully participate in the e-commerce, information and entertainment opportunities offered on-line. We salute the W3C's success in bringing industry and the disability community together to develop accessibility guidelines, and we encourage Internet users on both sides of the monitor to support Web accessibility.

-- Tom Tauke, Senior Vice President, Bell Atlantic

When Boeing says the Web can help us do business with "anyone, anywhere, any time," we mean anyone. Both our external Web site and our intranet are used by a large and diverse base of customers, employees, suppliers, and partners. We are committed to making those sites accessible to all users, including people with disabilities. Boeing applauds the Web Accessibility Initiative's efforts to simplify the development of accessible sites and encourages our vendors to adopt the Authoring Tool Accessibility Guidelines."

-- Ann Bassetti, Web Products Manager, Boeing Shared Services Group, The Boeing Company

Electricité de France is a group that employs a large number of disabled people, some of them with severe handicaps. We welcome this Recommendation as a new step towards more accessible work environments we could provide them. From a business to consumer point of view, we wish to greet a specification that will allow us, if tool vendors conform to these guidelines, to establish better contacts with our customers.

-- Laurent Prevosto and Daniel Glazman, Electricité de France

Since the design of Web pages affects accessibility of Web sites for people with visual impairments, the Hong Kong Blind Union supports the Authoring Tool Accessibility Guidelines which will help protect our equal rights to access the Web. Availability of authoring tools that support these guidelines will help organizations make their Web sites accessible. The Hong Kong Blind Union will promote awareness and implementation of the Authoring Tool Accessibility Guidelines to our government, public sector, and private sector.

-- Mr. Chong Chan Yau JP, President, Hong Kong Blind Union

The World Wide Web was originally envisioned as a read-AND-write medium; Web users are active participants, not a passive audience. The Authoring Tool Accessibility Guidelines embody that vision, promoting the creation of software to let everyone fully participate in the Web, as content creators and content users.

-- Kynn Bartlett, President, HTML Writers Guild.

IBM supports this W3C Recommendation and recognizes it as the standard for authoring tool accessibility. The Recommendation sets a challenging bar for tool manufacturers to meet, but, once met, it will benefit not only the tool users, but the millions of people who need accessible Web content. Our own TopPage and WebSphere Studio tools will be meeting checkpoints and aiding in the production of accessible content. IBM's participation in W3C and development of Home Page Reader are additional initiatives helping to make e-business accessible for everyone.

-- Jeffrey Barnett, IBM WebSphere Product Manager

We are pleased to see W3C encouraging the development of Web software products to enhance accessibility of Web sites through provision of guidelines that will facilitate development of such products. We understand the guidelines will enable software suppliers to provide authoring tools that facilitate the creation of accessible Web-based services and information. Canadians are increasingly using the Web as a tool for electronic commerce and personal development such as distance learning. Sites which facilitate access by all Canadians will obviously have an advantage.

-- Eleanor Zazaluk, Chair, Internet Advisory Committee, Treasury Board Secretariat, Government of Canada

The Authoring Tool guidelines are a highly leveraged step toward more accessible Web sites. Widespread adoption of the guidelines by companies that produce authoring tools - and in turn, widespread use of those tools - will make accessible Web sites the default rather than the exception. In addition, the guidelines can help encourage the wide range of manufacturers to make their authoring tools more usable by people with disabilities. Microsoft is proud to have been an active contributor to the development of these guidelines.

-- Greg Lowney, Director of Accessibility, Microsoft Corp.

The Authoring Tool Accessibility Guidelines help fulfill two basic needs of people with disabilities on the Web: access and participation. In July, 1999 the Portuguese Government's Council of Ministers approved a resolution requiring accessible Web content on public administration Web sites. The Ministry of Science and Technology will monitor, evaluate and support Web authoring tools that make this task easier. Web authoring tools are critical for education, work and full participation in the "Internet Society," and should be based on principles of accessible software design which enable authoring by people with disabilities.

-- Francisco Godinho, Adviser for the National Initiative for Citizens with Special Needs in the Information Society - Ministry of Science and Technology, Portugal

The full potential of the Web will only be realized when all the rich sources of information and content it contains are fully accessible. The W3C's Authoring Tool Accessibility Guidelines offers a significant enabling foundation that provides consistent support in Web content authoring tools for the creation of Web content that is accessible by all users. As a leading innovator in web-based multimedia and rich Web experiences, RealNetworks supports these guidelines and we fully intend to implement support for the guidelines in upcoming products.

-- Ben Rotholtz, General Manager, Systems and Tools, RealNetworks

The Royal National Institute for the Blind cannot overstress the important role that the World Wide Web Consortium is playing in recommending Authoring Tool Accessibility Guidelines, which support accessible content development and accessibility of the tools themselves. We fully endorse all steps taken that enhance the possibility of accessing electronic data across the Web by visually impaired people and people with other disabilities.

-- Steve Tyler, Royal National Institute for the Blind

Sausage welcomes the release of the Authoring Tool Accessibility Guidelines as a W3C Recommendation, and will implement and promote awareness of the Consortium's Web Accessibility Initiative to deliver increased functionality to customers of our HotDog Web authoring tools.

-- Rob Oliphant - General Manager Internet Tools, Sausage Software Limited

The SID@R (Web Accessibility Initiatives Seminar) of Real Patronato, Spain, considers that it is especially important that all people can be authors of information on the Web, as well as readers. The Authoring Tool Accessibility Guidelines are a comprehensive and clear document, and we will be pleased to have tools available that implement these guidelines that will enable more people to create Web content and to use the Web. SIDAR will promote awareness and implementation of these guidelines.

-- Emmanuelle Gutiérrez y Restrepo, SID@R Coordinator

Making the Web accessible to everyone is an important activity for W3C, and one which SoftQuad Software fully supports. The release of the Authoring Tool Accessibility Guidelines Recommendation continues this fine work. Our award-winning Web site creation tool, HoTMetaL PRO, was the first to incorporate several accessibility features, including prompting, to help make both browsing and authoring for the Web accessible to everyone.

-- Roberto Drassinower, CEO, SoftQuad Software Inc.

Les Guides d'Accessibilité des Outils Auteur représentent un grand pas en avant pour la création de futures pages Web accessibles. Toute l'équipe Amaya du W3C supporte de tout coeur ces guides et a déjà commencé leur implémentation dans Amaya, l'éditeur/navigateur expérimental du W3C. L'implémentation et la démonstration des recommandations du W3C est la tâche principale de Amaya, et l'implémentation des Guides d'Accessibilité des Outils Auteur sera l'une des grandes priorités de l'équipe de développement de Amaya.

-- Irène Vatton, Amaya Architect, W3C/INRIA

Electricité de France est un groupe qui emploie un grand nombre de personnels handicapés, certains souffrant d'un handicap très important. Nous accueillons très favorablement cette proposition de Recommandation qui représente pour nous un nouveau pas vers la fourniture d'environnements de travail adaptés à ces employés. Dans une optique plus Service, nous saluons une spécification qui nous permettra, si elle est respectée par les outils de production, de meilleurs contacts avec nos clients.

-- Laurent Prevosto and Daniel Glazman, Electricité de France

El SID@R (Seminario de Iniciativas sobre Discapacidad y Accesibilidad en la Red) del Real Patronato de Prevención y de Atención a Personas con Minusvalía, considera especialmente importante que todas las personas puedan ser autores de información en la Web, tanto como lectores. Las Directrices de Accesibilidad para Herramientas de Autor constituyen un documento claro y exhaustivo, y nos complacería contar con herramientas que siguiesen dichas pautas, lo que capacitaría a más personas para crear contenidos y para usar la Web. El SID@R promueve el conocimiento y uso de esas directrices.

-- Emmanuelle Gutiérrez y Restrepo, SID@R Coordinator

Fact Sheet for "Authoring Tool Accessibility Guidelines 1.0"

This "Frequently Asked Questions" (FAQ) page provides background on the World Wide Web Consortium's (W3C) Authoring Tool Accessibility Guidelines 1.0 Recommendation, released on February 3, 2000.

General Questions:
Background:
Availability of implementations:
Support and resources for developers:
About conformance:
Will conformant tools...

1. General Questions:

What is an authoring tool?

An authoring tool is software that people use to create Web pages and Web sites. Authoring tools include text editors, WYSIWYG ("what you see is what you get") editors, save-as-HTML conversion tools (word processors, spreadsheets, presentation software, etc.), tools that generate content from databases, multimedia editors, formating tools, and site management tools.

What is in these guidelines?

The Authoring Tool Accessibility Guidelines 1.0 (ATAG 1.0) include seven general guidelines, or principles, each of which has several checkpoints, or requirements -- twenty-eight all together. Checkpoints are assigned one of three priority levels. A companion Checklist of Checkpoints sorts all checkpoints by priority, including a set of relative-priority checkpoints, which address authoring tool support for checkpoints in the Web Content Accessibility Guidelines 1.0. The guidelines also include an introduction, information about how to indicate conformance to the document, and references.

How do authoring tools support the production of accessible Web content?

Authoring tools can support the production of accessible Web content by generating valid markup automatically; by checking the accessibility of content created; by prompting the author for necessary changes; and by informing the author how to create accessible content.

Why are these guidelines necessary?

Many of today's authoring tools create markup that is difficult for people with disabilities to access. Since the Web has become such a key information resource, it is important to ensure that people with disabilities can use the Web. The Authoring Tool Accessibility Guidelines 1.0 will make it much easier for Web site developers to create sites that meet accessibility goals established by the W3C's Web Content Accessibility Guidelines 1.0, and will make it possible for more people with disabilities to create content themselves.

Will there be a demand for authoring tools that implement these guidelines?

There is an increasing number of public and private-sector organizations that are interested in ensuring accessibility of their Web sites, and in some cases, governmental policies that require accessibility of certain kinds of Web sites. These organizations are already requesting information on tools that produce accessible content, and we expect the demand to increase.

2. Background:

What is the difference between these guidelines and other Web accessibility guidelines?

The Web Content Accessibility Guidelines explain how to design Web pages that are accessible. The User Agent Accessibility Guidelines explain how to develop browsers and multimedia players that can be used by people regardless of disability. The Authoring Tool Accessibility Guidelines explain how to develop authoring tools that make it easier to produce accessible Web pages that conform to the Web Content Accessibility Guidelines.

Who has been involved in developing these guidelines?

The Authoring Tool Accessibility Guidelines Working Group (AUWG), which developed ATAG 1.0, includes representatives of industry, the disability community, and research organizations. Active members during development of these guidelines included IBM, Lotus Corporation, Microsoft Corporation, the HTML Writers Guild, the Adaptive Technology Resource Centre of Canada, TRACE Research and Development Center, Texas School for the Blind and Visually Impaired, Smith-Kettlewell Eye Research Institute, and the Visually Impaired Computers Users' Group of New York. In addition, the guidelines received review and comment during their development by members of the Web Accessibility Initiative (WAI) Interest Group, by W3C Member organization representatives, and by other software developers, and all feedback was reviewed and incorporated where relevant.

How does one learn more about the Web Accessibility Initiative (WAI)?

The Web Accessibility Initiative home page includes a variety of information about WAI: resources, events, Working Group activities, involvement opportunities, and sponsorship opportunities.

What is the role of W3C in Web accessibility?

W3C hosts the Web Accessibility Initiative, bringing expertise in accessibility to the W3C Member organizations and to the Web community at large. New W3C specifications are reviewed to ensure that they do not compromise and where possible that they enhance the accessibility of the Web, ensuring that the Web is developed to its full potential for all its users.

3. Availability of Implementations:

How soon will there be tools available that implement these guidelines?

At the time of the release of ATAG 1.0, every requirement of the Guidelines has been implemented by one or more existing tools, though no tool yet satisfies all checkpoints. In addition, authoring tool developers are planning ATAG 1.0 support in upcoming products, indicated among the wide range of testimonials.

What are the best tools available now for creation of accessible Web sites?

Since no tool yet conforms to any ATAG 1.0 conformance level at the time of ATAG 1.0 release, the most appropriate tool for a given author may depend upon the needs and skills of the author in consideration with various available tools. Does the authoring tool produce valid markup? Tool output can be tested against W3C validators. Does a tool make it easy or difficult to add accessibility information into pages, and does it check accessibility semi-automatically? If not, existing evaluation tools can be used in conjunction with existing authoring tools to facilitate checking. Check the WAI home page for links to updated information on implementation status of ATAG 1.0 in different authoring tools.

If a Web site developer wanted to evaluate their current authoring tool, where would they start?

The Web site developer could review the Checklist of Checkpoints for Authoring Tool Accessibility Guidelines 1.0 and accompanying Techniques for Authoring Tool Accessibility, and compare the authoring tool against these. This would require some familiarity with ATAG 1.0 as well as the Web Content Accessibility Guidelines. Alternatively, the Web site developer could ask the developer of the authoring tool how soon that product will support ATAG 1.0.

Will W3C's own tools be conformant to these guidelines?

W3C has a testbed authoring tool/browser known as Amaya. The Amaya development team has developed a workplan to implement ATAG 1.0, and has begun development on the implementations.

4. Support and Resources for Developers:

Are the checkpoints prioritized in some way, so a developer will know what features are most important?

ATAG 1.0 has three priority levels, which relate to the goals of the document. Priority one checkpoints are essential to meeting the goals of the document; priority two checkpoints are important to meeting the goals; and priority three checkpoints are beneficial to meeting the goals. The goals of the document are that the authoring tool be accessible; that it generate accessible content by default; and that it encourage the creation of accessible content. In addition, some checkpoints have relative priority, in that they reference the priority levels of checkpoints from the Web Content Accessibility Guidelines 1.0 for which they provide implementation guidance in authoring tools.

What kind of reference materials are available for tool developers who want to implement these guidelines?

The Checklist of Checkpoints for Authoring Tool Accessibility Guidelines 1.0 that accompanies these guidelines provides a reference listing, by priority, of all ATAG 1.0 checkpoints, for assessing current product features with regard to ATAG 1.0. A W3C Note Techniques for Authoring Tool Accessibility 1.0 describes strategies for implementing the checkpoints and provides references to material relevant for specific topics such as the accessibility of multimedia content.

Are there any open-source materials or reference implementations available?

Techniques for Authoring Tool Accessibility 1.0 includes references to tools, including open-source tools, that demonstrate different strategies for meeting the checkpoints. In addition, W3C's continuing development of its open-source test-bed authoring tool/browser Amaya has started to implement ATAG 1.0.

What other resources are available to support accessibility of the Web?

The Web Accessibility Initiative publishes a wide range of resources to support accessibility of the Web. Many of these are linked from the "resources" section of the WAI home page, such as other guidelines and techniques documents; easy introductions to Web accessibility (Quick Tips, Curricula, WAI Overview, etc.); technical references (on HTML, CSS, SMIL, and other W3C technical reports); and a collection of pages with relevant reference links (policies, alternate browsers, evaluation tools, etc.).

5. About Conformance:

Are there different levels of conformance to ATAG?

ATAG 1.0 has three levels of conformance, which correspond to its three priority levels. Authoring tools that satisfy all priority one checkpoints conform at "Level-A"; authoring tools that satisfy all priority one and two checkpoints conform at level "Double-A"; and authoring tools that implement all three priority levels conform at level "Triple-A". All conformance levels include relative priority checkpoints.

How will I know if a tool that I want to buy supports these guidelines?

An authoring tool that supports these guidelines will most likely claim conformance at the appropriate conformance level. Further information on claims of conformance for ATAG 1.0 is available on the Web. The Authoring Tool Guidelines Working Group will continue to compile implementation information, available at the time of this release in a preliminary report only, and list authoring tools that conform to different ATAG 1.0 conformance levels as those tools become available and as information about new tools becomes available to the Web Accessibility Initiative.

Do authors have to use conformant tools to create accessible Web pages?

It is possible to create accessible Web pages with non-conformant tools, by using either a text editor, WYSIWYG, or other editor, and directly applying the Web Content Accessibility Guidelines 1.0 while creating the page. This may involve more steps than if using a conformant tool, for instance going into the source code to ensure that the tool is generating valid code, or performing steps manually to check the accessibility of a page. For authors who are less familiar with the Web Content Accessibility Guidelines 1.0, authoring tools that conform to ATAG 1.0 may significantly facilitate production of accessible Web sites.

6. Will Conformant Tools...

...be easy or difficult to use?

Authoring tools are easy or difficult to use according to the level of user experience they presume. The fact that a tool supports ATAG 1.0 should not directly affect its ease of use, with the exception that when authoring accessible pages, an ATAG-conformant tool would be easier to use than a similar tool that was not ATAG-conformant since the first tool would automate some steps involved in making a Web page accessible.

...be usable by people with disabilities?

An ATAG-conformant tool should be usable by people with disabilities since accessibility of the tool itself is covered by the guidelines.

...allow people to create interesting Web pages?

Conformant tools will allow people to create interesting Web pages. The degree of "interest" in a Web page can be related to the design skills of the author, the nature of the content on the page, and the capabilities of the authoring tool with regard to support for different markup languages (HTML, SMIL, SVG, etc.) and presentation formats (CSS1, CSS2, etc.). Whatever the capabilities of the tool, ATAG 1.0 provides guidance on how to ensure that those capabilities support accessibility.

...fully automate the creation of accessible content?

While ATAG-conformant tools can automate some accessibility requirements, such as production of valid markup, they cannot automate all accessibility requirements. For instance, they cannot automate reliable production of alternative text for a complex image used in a specific context -- however, they may be able to automate re-use of that alternative text the next time that the image appears on a Web site.

...produce content that works across different kinds of browsers?

One of W3C's primary goals is to promote the interoperability of the Web. ATAG 1.0 emphasizes production of content that is consistent with established Web standards, and which therefore has the greatest chance of working across current browsers as well as the browsers of the future, as Web technologies converge.

...explain how to caption audio or describe video?

ATAG-conformant tools include help files which explain how to perform potentially unfamiliar steps such as captioning audio or describing video for the first time, where relevant to the type of tool. In addition, sample or tutorial files accompanying conformant tools would include some examples of how to author accessibility information.

...provide some way to verify accessibility of Web pages?

ATAG-conformant tools are required to provide functions for validating accessibility of the Web pages they produce.

...allow the user to turn off prompts, alerts, checking, etc., if he or she didn't want to use them?

The extent of configurability depends on the type of tool. In many tools, functions such as prompting, alerts, and validation could be adjusted or turned off by the user; while other tools might always have accessibility features "turned on."

...require the user to know much HTML to make accessible Web pages?

This depends on the type of tool. Some tools assume no knowledge of HTML or other markup language, and others either require some knowledge, or allow the user to edit source code directly when needed. With tools that do not conform to ATAG 1.0, the user often must know some HTML to be able to fix accessibility problems that the tool creates.

...require the user to convert their existing code?

This depends primarily on the type of tool used to produce existing source code. A page already using valid code should not require conversion for the purpose of accessibility, although it might require the addition of information such as providing a summary for a table. A page containing large amounts of inaccessible markup from a previous authoring tool could require conversion or "repair" of the source code. Some conformant tools may make conversions automatically; while others might reject code that is invalid.