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Web Posted on: December 2, 1998 December 2, 1998

The Ongoing Evolution of the WAI Authoring Guidelines

Gregg C. Vanderheiden, PhD
gv@trace.wisc.edu

Wendy Chisholm
chisholm@trace.wisc.edu

Trace R&D Center
5901 Research Park Blvd.
Madison, WI 53719

Introduction

Since December of 1997 the WAI Page Authoring Guidelines have taken many faces. Originally organized by HTML topic areas with over fifty guidelines, and containing many confusing references to interim and future solutions, the guidelines document has evolved into a more robust, and hopefully timeless set of directives. The goal of the most recent version was to make the guidelines as easy to understand and follow today as they are tomorrow. Techniques have been separated from guidelines, such that there are nineteen guidelines with over sixty supporting techniques. Since the techniques are discussed in detail in their own document, we expect them to continue to evolve as new ideas, and technologies are introduced. In this paper/presentation, we discuss the current state of the guidelines and the technologies they cover, as well as looking to the future of guidelines and techniques for emerging technologies.

Current status

The most recent release (Vanderheiden, et al, 1998a) has grouped the guidelines into three meta-guidelines:

  • Make sure pages transform gracefully across users, techniques, and situations.
  • Provide context and orientation information for complex pages or elements.
  • Maximize usability by following good design practices.

Here are the guidelines as they appear in the most recent version:

A. Transform Gracefully

Make sure pages transform gracefully across users, techniques, and situations

To "transform gracefully" means that a page remains usable despite user, technological, or situational constraints. In order to use the page at all, some users may need to "turn off" features specified by the author (font size, color combinations, etc.). For example, a person with low vision might need to display all text in 36-point font, so any formatting based on an author-determined font size will fall apart.

To create documents that transform gracefully, authors should:

  • Ensure that all the information on the page may be perceived entirely visually and entirely through auditory means, and that all information is also available in text.
  • Always separate the content on your site (what you say), and the way you choose to structure that content (how you organize it), from the way the content and structure are presented (how you want people to "see" it).
  • Ensure that pages will be operable on various types of hardware including devices without mice, with small, low resolution, or black and white screens, with only voice or text output, without screens, etc.

Guidelines A.1 - A.12 address these issues.

A.1. Provide alternative text for all images, applets, and image maps. [Priority 1]
A.2. Provide descriptions for important graphics, scripts, or applets if they are not fully described through alternative text or in the document's content. [Priority 1]
A.3. Provide textual equivalents (captions) for all audio information [Priority 1]
A.4. Provide verbal descriptions of moving visual information in both auditory and text form (for movies, animations, etc.). [Priority 1]
A.5. Ensure that text and graphics are perceivable and understandable when viewed without color. [Priority 1]
A.6. Indicate structure with structural elements, and control presentation with presentation elements and style sheets.[Priority 2]
A.7. Ensure that moving, blinking, scrolling, or auto-updating objects or pages may be paused or frozen. [Priority 1]
A.8. Provide supplemental information needed to pronounce or interpret abbreviated or foreign text. [Priority 2]
A.9. Ensure that pages using newer W3C features (technologies) will transform gracefully into an accessible form if the feature is not supported or is turned off. [Priority 1]
A.10. Elements that contain their own user interface should have accessibility built in. [Priority 2]
A.11. Use features that enable activation of page elements via input devices other than a pointing device (e.g., via keyboard, voice, etc.). [Priority 1]
A.12. Use interim accessibility solutions so that assistive technologies and older browsers will operate correctly. [Priority 2]

B. Context and Orientation

Provide context and orientation information for complex pages or elements.

To provide context and orientation information means that additional information is provided to help users gain an understanding of the "big picture" presented by a page, table, frame, or form. Oftentimes users are limited to viewing only a portion of a page, either because they are accessing the page one word at a time (speech synthesis or braille display), or one section at a time (small display, or a magnified display).

To create documents that provide context and orientation information, authors should:

  • Structure and group information.
  • Clearly label the structure and groups.

Guidelines B.1-B.3 address these issues.

B.1. For frames, provide sufficient information to determine the purpose of the frames and how they relate to each other. [Priority 1]
B.2. Group controls, selections, and labels into semantic units. [Priority 2]
B.3. Ensure that tables (not used for layout) have necessary markup to be properly restructured or presented by accessible browsers and other user agents. [Priority 1]
B.4. Wherever possible, create "good" link phrases. [Priority 2]

C. Good Practices

Maximize usability by following good design practices.

Good design is accessible design and vice-versa. For instance, many of the practices that lead to more accessible pages also make them accessible to indexing engines as well as more usable by all users. Good design practices include consistency, generality, simplicity, reuse, and validation.

C.1. Only use technologies defined in a W3C specification and use them in an accessible manner. Where not possible, provide an accessible alternative page that does. [Priority 1]
C.2. Provide mechanisms that facilitate navigation within your site. [Priority 3]
C.3. Create a single downloadable file for documents that exist as a series of separate pages. [Priority 3]

Techniques covered in the guidelines

In the guidelines document, each guideline has at least one technique associated with it. Techniques are discussed in more detail in a separate document (Vanderheiden, et al, 1998b). Currently, the techniques cover ways to:

  • use HTML to structure a page using:
  • Headers
  • Hypertext
  • Lists
  • Tables
  • other structural elements.
  • use HTML to create non-frame equivalents to frame pages,
  • use HTML to create accessible forms,
  • include accessible audio and video,
  • use style sheets to control presentation,
  • embed images and image maps,
  • use HTML to embed non-W3C technologies such as JavaScript, Java applets, PDF files, and other such technologies,
  • and a list of good design practices.

Challenges for the future

Today, the techniques document is very focused on HTML. There is a need to cover other W3C technologies (such as Cascading Style Sheets, JavaScript/ECMAScript, XML, SMIL, etc.) in more detail, perhaps each with its own techniques document. The latest structure should allow the WAI to tackle these related issues in an organized and efficient way.

Non-W3C technologies are a different matter, albeit growing in number and inaccessibility. Fortunately, one of the quickest growing technologies, Java, is being tamed by Sun and IBM who have created a set of guidelines for how to author accessible Java applications/applets. However, there are many other technologies that appear on Web pages that are not accessible and this is only likely to grow.

Conclusion

While the WAI Page Authoring guidelines have evolved to become more usable, and easy to understand and use, the focus in the near future will be on the evolution of the techniques that accompany the guidelines. Currently, the techniques are very HTML based, leaving out an array of other W3C technologies. Still to be debated is what needs to be done about non-W3C technologies.

References

Vanderheiden, Gregg C.; Chisholm, Wendy A.; Jacobs, Ian. (1998a) WAI Accessibility Guidelines: Page Authoring. Available: http://www.w3.org/WAI/GL/WD-WAI-PAGEAUTH.html

Vanderheiden, Gregg C.; Chisholm, Wendy A.; Jacobs, Ian. (1998b) Techniques for "WAI Guidelines: Page Authoring". Available: http://www.w3.org/WAI/GL/wai-gl-techniques.html

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