W3C logo Web Accessibility Initiative (WAI) logo

Last modified: $Date: 2000/11/08 08:27:06 $

WAI Web Content Accessibility Guidelines:
Record of Working Draft Revisions

This page is for maintaining a record of changes between each revision of the working draft for the page author guidelines. If you find the list is incomplete or inaccurate please contact the editor, Wendy Chisholm, at chisholm@trace.wisc.edu.

Version WAI-WEBCONTENT-19990505

This version is a Recommendation.

This change list does not include some editorial changes to the introduction, guidelines rationales, or glossary during the Proposed Recommendation period.


Guideline 1

Guideline 3

Guideline 4

Guideline 5

Guideline 6

Guideline 7

Guideline 9

Guideline 10

Guideline 11

Guideline 13

Guideline 13

Version WAI-WEBCONTENT-19990324

This version is a Proposed Recommendation.

General changes


Related documents

How the guidelines are organized



The following guideline numbers refer to the numbers in this version of the document.

Guideline 1

Guideline 2

Guideline 3

Guideline 4

Guideline 5

Guideline 6

Guideline 7

Guideline 8

No changes.

Guideline 9

Guideline 10

Guideline 11

Guideline 12

Guideline 13

Guideline 14



Version WD-WAI-PAGEAUTH-19990316

This is a revision of the Feb 26, 1999 revision in last call. This draft is meant to indicate progress in accounting for resolved issues and editorial changes.

Document structure changes

  1. Moved section on "Comments" to status section.
  2. Added a section entitled "Related documents" after the status section that explains the relationship between the guideilnes doc, the checklist (which is an appendix to the guidelines) and the techniques document. In this section, there is more "warning" about unsupported attributes and elements. There is also a list of tools (including navigation tools) in the Techniques document to help readers track information.
  3. Moved introductory matter before guidelines to a new section (2) immediately after the Introduction.
  4. Made priorities and conformance their own sections (4 and 5 respectively).

Document usability changes

  1. Removed lots of STRONG and B elements from rationales.
  2. Section numbering scheme now the following: Header and reference sections are not numbered. Body sections use 1, 2, 3.... Appendixes use A, B, C...
  3. Navigation tools added: links after each guideline to next guideline, previous, and table of contents (suggestion from Gregory Rosmaita).
  4. Links after guideline rationale to individual checkpoints in the guideline.
  5. Long descriptions added to images.
  6. Most of the links from the guidelines to the techniques are now clearly marked as leading there. (The few remaining will be cleaned up soon.)
  7. Link text reviewed to ensure that it stands on its own.
  8. Links to definitions are marked up as such (class="dfn-instance") and presented specially through style sheets (visually, with green text).
  9. All Links to references at the end of the guidelines have bracketed link text.
  10. All checkpoints are ordered by priority within a given guideline EXCEPT for 13.4, intentionally left as the last checkpoint of that section. Checkpoints that have been renumbered due to reordering alone are not listed here. Checkpoints moved for other reasons are listed below.
  11. The checkpoints in the appendix list of checkpoints are grouped by priority, subgrouped by topic, and sorted by checkpoint number. They link to the definitions of the checkpoints in the guidelines document.
  12. Link in navigation bar to priorities removed.
  13. As per the guidelines, provided a link to skip over the ascii cow.

Editorial changes

There have been a lot of editorial changes (too many to list exhaustively) based on very helpful comments from many reviewers. Some more important changes include:

  1. The wording of the priorities has been revised slightly.
  2. The word "technique" is no longer defined as a first-class object like "checkpoint" or "guideline". The "Techniques Document" describes implementation, but as Eric Hansen pointed out, the term Technique was used in a variety of situations in the Techniques document. Links from the Guidelines to the Techniques document simply refer to "Techniques".
  3. Use of "content developer" rather than author in most places.
  4. Use of "provide" rather than "design" or "use" where appropriate. (grin)
  5. Removal of subjective language such as "if possible", "where possible", etc. Removed from checkpoints 5.6, 8.5, 10.1, 11.1, 15.1, 16.1, 13.3.
  6. Verification of use of "should" and "must" (to see that corresponds to Priority 1 and 2).
  7. To be verified. There are two terms clearly defined: "equivalent" and "description". The former refers to functional substitute, the latter to appearance and sound. There are text and non-text equivalents and text and non-text descriptions. The terms "long description" and "brief description" have been removed from the document (except perhaps in the techniques document, which still needs lots of editing.)
  8. Reviewed (and defined in glossary) the term "content". Content refers to what is said and the markup to build it.

Changes to checkpoints

  1. 1.1 and 1.2: "title" on OBJECT eliminated as an example of how to provide a text equivalent. Added cross-reference from 1.2 to 8.5 and guideline 10.
  2. 1.5: added: Priority 1 - Provide client-side image maps instead of server-side image maps except where the regions cannot be defined with an available geometric shape.
  3. 1.7: changed to differentiate server-side and client-side cases of redundant text links.
  4. 2.2: moved to 1.3 since refers to text equivalents primarily.
  5. 2.4: moved to 3.4 since relates to audio.
  6. 3.4: wording changed.
  7. 4.1: added a note that when text is purely decorative, alternative mechanisms are unnecessary.
  8. 4.2: wording changed.
  9. 6.2: Proposed priority change - Priority 2 for first occurrence in document, priority 3 thereafter.
  10. 7.4: Don't talk about captions to describe layout tables, just "summary" attribute.
  11. 8.1: example removed since confusing.
  12. 8.5: wording changed and more rationale.
  13. 9.1 and 9.2: Wording "Until user agents ..." added to emphasize UA responsibility here.
  14. 13.3 and 13.4: merged into 13.3. Provide information so that users may receive documents according to their preferences (e.g., language, content type, etc.). Priority 3. Encouraged content negotiation.
  15. 15.3: Example in HTML of LINK element plus rel/rev attributes to create nav bars (some user agents do this).
  16. 15.6: wording changed, otherwise too much like guideline 15.
  17. 16.2: added note about importance to non-readers.

Changes to guidelines

  1. Guideline 2: Removed "important" from guideline text since "important" not a part of every checkpoint therein.x
  2. Guideline 4: Removed "perceived" from subhead.
  3. Guideline 6: Added notes to advise content developers (1) not to misuse markup for presentation effects and to (2) not misuse markup for fear of creating access problems (i.e., use tables for data!).
  4. Guideline 6: New guideline text: Clarify Natural Language Usage. Also, last sentence of rationale changed.
  5. Guideline 7: Subhead changed.
  6. Guideline 8: Removed note about "at a minimum" and moved to checkpoint 8.4, removing "at a minimum" part.
  7. Guideline 9: removed bout guideline not applying for server-side redirects because the note didn't apply to the entire guideline. Instead, note moved to checkpoint 9.1.
  8. Guideline 11: edits to rationale
  9. Guideline 13: Note about using alt pages reworded somewhat.
  10. Guideline 14: Supply changed to Provide for consistency.
  11. Guideline 16: edits to rationale.

Changes to conformance

  1. Conformance levels are now A, Double-A, and Triple-A.
  2. An sample conformance statement is provided.
  3. Eric Hansen's full proposal has not been incorporated.

Changes to validation

  1. Title changed from "Testing" to "Validation"
  2. No direct links to techniques document. Instead, one link in rationale links to entire section on validation in Techniques Document.
  3. Edits based on Eric Hansen comments
  4. Validation 8: Added "grammar checker".
  5. Validation 9: New. About human review/editing.
  6. Validation 10: New. Review from disabled users.

Changes to glossary

  1. Since there is more in the glossary now, there is less text in some rationale sections (e.g., Guidelines 2 and 3).
  2. Added, but did not define, "accessible"
  3. Added a discussion of content, structure, and presentation.
  4. Added a definition of "equivalent" and "description". Text equivalent defined there.
  5. Added "navigation mechanism" (see Guideline 15)
  6. Added "style sheets"
  7. Added "User agent"

Changes to references

  1. Added [PNG]

Version WD-WAI-PAGEAUTH-19990226

  1. Broke identify-changes into 2 checkpoints, identify-changes=p1, identify-lang=p3,
  2. Changed "alternative text" to "text equivalent" as appropriate.
  3. Added text to site-map checkpoint to emphasize usefulness.
  4. Combined guidelines descriptions and verbal-descriptions (previous 2 and 4, now 2)
  5. Added details of what is in archive files (available formats section),
  6. Added comment about minimizing page duplication,
  7. Added note that TEchniques will evolve more rapidly than guidelines,
  8. Critical -> important,
  9. Cleared up text about server redirect,
  10. Removed text-imap-links since alt-area covers it,
  11. Cleared up meaning of operating in a graphical environment,
  12. Removed must from 14.3,
  13. Added use-metadata (Pri 2) since RDF be come a REC yesterday,
  14. Deleted 16.11 and merged idea with 16.10
  15. Restructured lists of checkpoints for readability.
  16. Unified language of examples (e.g., "For example, in HTML use the ....)
  17. Edited the whole document for grammar, syntax, etc..
  18. Shortened guideline text. After each guideline, there's a subheader with more elaborate text.
  19. Edited all the rationales to read better.
  20. Using W3C global style sheet.
  21. Reworded alt-images to clarify that specific recommendations are given for vario us types of images.
  22. Split user-control-refresh into no-periodic-refresh and no-single-refresh
  23. Edits to abstract, status section, introduction, guidelines organization, and conformance statment. Also fixed ascii cow
  24. added checkpoint for device-indie events
  25. updated use-style-sheets to more generic proposal,
  26. added new 8.1 - avoid tables for layout,
  27. made wording for link-bypass more generic
  28. added link to DOM within new defn for DHTML
  29. Removed sections A and B and renamed single section,
  30. put all intro text from A a nd B at beginning of new section,
  31. replaced some guideline numbers with proper re placeable gadgetry,
  32. removed H3 from appendix
  33. Added HRs, now first two and last two sections aren't numbered, spell fix
  34. changed some should's to must, may's to should, and a must to a may
  35. made color contrast a P2 rather than P1
  36. added introduction
  37. added conformance statement
  38. edited intro to A

Version WD-WAI-PAGEAUTH-19990217

Editorial changes:

Version WD-WAI-PAGEAUTH-19990210

  1. Links added from tables (a.8) to a.13.5 and a.6.4 2.
  2. Reworded a.9.5 (for pages that use style sheets...) to include "presentation markup" as well as general editing to make read better.
  3. Reworded A.1.3 (for all image map links, provide alt-text) so as to not confuse the reader if they are using A and MAP
  4. Reworked the checkpoint re: OPTGROUP since said "hierarchy" and OPTGROUPs can't be nested.
  5. Deleted parens around 2nd group of users in A.5
  6. Changed A.9.1 (provide fallback page for pages w/dynamic content, e.g. NoFRAME) from P1 to P2, ala 1/28 telecon
  7. Reworded A.14.4 to be more general
  8. Added a checkpoint to address content negotiation (a.14.5 - content-negotiat ion)
  9. Replaced the statement in B.1.2 "in HTML, use "longdesc". Until "longdesc" is widely supported, also use a d-lin k or invisible d-link" with "in HTML, use "longdesc" or a d-link."
  10. Changed title to Web Content Accessibility Guidelines
  11. Added the term "content developers" to prose
  12. Added statement about title change to status sections
  13. Updated copyright statement
  14. Added checkpoint to A.6 re: text, markup, and math.
  15. Added a list of W3C technologies (such as MathML, SMIL, HTML, XML, etc.) to A.14.1
  16. Mention MathML and SMIl in intro to A 2.
  17. Include link to "math included in images" in A.1 3.
  18. Rewrote A.1.6 (ascii art)
  19. Included cognitive disabilities in rationale for a.7 5.
  20. Included http in example for a.7.1 6.
  21. Rewrote the first three checkpoints for tables (a.8) to be more generic and to include Daniel's algorithm
  22. Included pointers to other checkpoints that contain table checkpoints.
  23. Modified the note re: pdf translation ala Jason White suggestions.
  24. Added visual disabilities to rationale of b.1
  25. Changed "name" to "title" in B.1.2
  26. Links in the table of contents have been shortened to the beginning of the guideline rather than the entire phrase.

Version WD-WAI-PAGEAUTH-19990115

  1. A new checklist has been added.
  2. Indexes removed from Guidelines and Techniques documents. These have been replaced by the checklist.
  3. HTML examples have been validated.

Version WD-WAI-PAGEAUTH-19990104

  1. "headers attribute" added to the list of attributes in A.8.3

Version WD-WAI-PAGEAUTH-19981207

  1. Links to techniques are working - not all of the content is in the techniques document yet, but the place holders now exist.
  2. It is now available in: plain text, HTML as gzip'ed tar, HTML as zip, PostScript, and PDF.
  3. Comments from editors are in red and begin "Editor:"
  4. Technique lists are now flat. Thus every technique is referred to by three numbers: section, guideline, technique. Organized this way, the techniques all make sense when read out of context.
  5. The list of techniques by priority appears at the end of the techniques document rather than the guidelines document.

Version WD-WAI-PAGEAUTH-19981117

  1. Major restructuring:
    1. C.3 (bundle documents for off-line reading) and B.4 (create good link phrases) have been moved from being guidelines to techniques in C.2 (provide mechanisms to facilitate navigation).
    2. Parts of C.2 were split into a new C.3 - " Use language and formats that facilitate comprehension of information." Instead of adding Eric Hansen's "disclaimer" to the abstract, we added 2 techniques toC.3.
    3. C.1 (use w3c technologies) became A.14
    4. B.3 (tables) became A.8 and the following technique added, " If a table is used purely for layout, do not use any structural markup for the purpose of visual layout. For example, in HTML the table header (TH) element causes the contents of a cell to be displayed centered and in bold. Other attributes of a table, such as a caption describing the layout purpose and content of columns is valuable, particularly if some cells become navbars, frames, images, imagemaps, or lists of links."
    5. Section A was reordered to flow better - all of the scripting and programatic stuff appears together.
    6. B.1 and B.2 were combined into B.1 (" B.1 Provide context and orientation information for complex pages or elements.")
    7. With all of the combining and moving around, All of the items in C (Good Design) are now parts of A and B (C.2 and C.3 became B2 and B.3).
  2. The introduction to "Transform Gracefully" was expanded to more clearly specify how HTML can be accessible (with an explanation of screen readers) so as not to frighten people away (in response to the results of Paul Adelson's study).
  3. The techniques were generalized so that they might be more applicable in the future. All of the HTML examples are explicitly identified as HTML.
  4. A.9 modified to include technologies other than W3C defined. The guideline and rationale now read, " Ensure that pages using newer technologies will transform gracefully into an accessible form if the technology is not supported or is turned off. [Priority 1]

    The everchanging landscape of technologies available on the internet is influenced by W3C Recommendations (such as HTML) and proprietary formats (such as ShockWave, and PDF). However, with each new release of Recommendations, browsers, or plug-ins, new features are added that may not be completely backwards compatible. For example, HTML 4.0 added the ability to attach style sheets to a page and to embed scripts and applets into a page. Older browsers ignore new features and some users configure their browser not to make use of new features. These users often see nothing more than a blank page or an unusable page when new features do not transform gracefully."

  5. The following sentence was added to the rationale of A.8 (now A.7), " This also means that the predominant language on the page must be identified, as there is no "default" language."
  6. Scripts added to A.10
  7. Warning text was added to C.1.2 (alternative pages - now A.14) to clarify why alternative pages are a last ditch option.
  8. Technique C.1.3 (now A.14.3) was added: When linking to resources that are not W3C technologies, indicate what type of resource you are linking to. For example, to link to a PDF file from an HTML document, set the "type" attribute to "application/pdf" on the A element. [Priority 3]
  9. Replaced the numbered name anchors with logical names.
  10. Added to the rationale about blink rates text regarding changes from light to dark: People with photosensitive epilepsy can have seizures triggered by flickering or flashing in the 4 to 59 flashes per second (Hertz) range with a peak sensitivity at 20 flashes per second as well as quick changes from dark to light (like strobe lights). [see http://lists.w3.org/Archives/Public/w3c-wai-gl/1998JulSep/0046.html]
  11. C.1 (now A.14) wording changed to be more inclusive of non-W3C technologies, "Wherever possible use a W3C technology, in accordance with guidelines on its proper use. Where this is either not possible, or results in material that does not transform gracefully you must provide an alternative version of the content that is accessible. [Priority 1]"
  12. New section (1.8 Browser Support) added to techniques to link to features that are not yet supported or not supported widely, such as OBJECT, accesskey, etc. Added a paragraph in the abstract to link to this section.
  13. Definitions added for Braille display, Collate, and Link phrases (within the context rather than in appendix).
  14. "Appropriately" is no longer used ambiguously.
  15. The following two techniques were added to the NEW B.2 (facilitate navigation):

Version WD-WAI-PAGEAUTH-19980918

  1. Definitions were added to the appendix for Applet, Braille, Image, Image map, Page authors, Screen magnifier, and Screen reader
  2. C.4 ("Validate your pages and asses the accessibility...") was moved into its own Appendix (A: testing).
  3. A.13 ("If all else fails...provide an alternative page") was incorporated into C.1 ("Only use W3C technologies, where not possible provide an alternative").
  4. As usual, quite a few slight changes in wordings.

Version WD-WAI-PAGEAUTH-19990908

  1. "Important" is defined in Appendix A and modifies "graphics, scripts or applets" in A.2.
  2. The use of "WWW documents" was replaced with "Web documents"
  3. Instances of "specification" have been replaced (where appropriate) with "W3C specification."
  4. Text and links have been added to A.1 ("Provide alternative text...") to make it easier to find out what needs to be done for spacer images, images used as list bullets, etc. The rationale was updated to include the phrase, "any user who cannot or has chosen not to view graphics."
  5. A.1.7 now says, "If OBJECT is used to incorporate an image, applet, or script into a page, use any of the many ways to convey that information in cases where the OBJECT cannot be perceived, such as with "title" or within the body of the OBJECT element. [Priority 1]" and A.2.2 is similar.
  6. A link was added from A.7 to the discussion of structural vs. presentation elements in the techniques document.
  7. A.7.4 no longer says that the flicker rate has to be in a certain "flashers per second" range, the range is given in the rationale.
  8. The priority for A.12.5 was changed to P2 in all instances (we missed a few last time around).
  9. C.1 was slightly reworded to become, "Only use technologies defined in a W3C specification. Where not possible, provide an accessible alternative."

Version WD-WAI-PAGEAUTH-19980903

  1. The main document is now the linear form and the table is a supplemental "overview."
  2. Added a second paragraph to the Abstract.
  3. The third priority was changed from "This guideline should be followed..." to "This guidelines may be followed..."
  4. A1.4 previously read "Don't use server-side image maps unless the same functionality or information is available in an alternative accessible format." It now reads, "If server-side image maps must be used,
    1. Provide text links for each hotspot in the image map. [Priority 1]
    2. Provide alternative text for the image map image (see A.1.1) [Priority 1]"
  5. A.5 was previously, "Design documents in a way that allows alternative presentations to be provided." The only technique for this guideline was, "Ensure that the source of each frame is an HTML file." This guideline was discarded and the technique was incorporated into A.9.
  6. Since A.5 was deleted, the rest of section A had to be renumbered.
  7. The first two techniques of A.7 were combined into one: "Movement should be avoided when possible, but if it must be used, provide a mechanism to allow users to freeze motion or updates in applets and scripts or use style sheets and scripting to create movement. (see also A.10) [Priority 2]"
  8. The following technique was added to A.6 (as A.6.3) "Mark up quotations with the Q and BLOCKQUOTE elements. Do not use them for formatting effects such as indentation."
  9. The previous A.6.4 ("Do not use an image map to create a set of buttons in a form. Instead, use separate buttons or images (accompanied by alt-text). [Priority 2]") was moved to A.1.5.2 and grouped with the other techniques on image maps and alt-text.
  10. The previous A.13.1 ("Until user agents and screen readers are able to handle text presented side-by-side, all tables that lay out text in parallel, word-wrapped columns require a linear text alternative (on the current page or some other). [Priority 1]") was moved to A.12.5 and became a Priority 2.
  11. Two appendicies were added. The first lists the guidelines grouped by priority, the second lists the techniques grouped by priority.

Version WD-WAI-PAGEAUTH-19980825

  1. Many rewordings were made throughout the document to make it easier to understand.
  2. The introductory titles of each section have become more complete.
  3. A new term, "transform gracefully," was created and defined to replace the controversial "fail gracefully."
  4. A table of contents, abstract and other introductory information (mostly from the last public draft) have been included.
  5. The definitions of the priorities are stronger.
  6. The first three sections (A. Ensure that information is accessible via different senses, B. Ensure that the information can be displayed on different technologies, and C. Make sure that your page will be operable with different devices) were combined into a single section called, "A. Make sure pages transform gracefully across users, techniques, and situations."
  7. The previous B.2 ("Use elements and attributes appropriately.") became A.7. "Indicate structure with structural elements, and control presentation with presentation elements and style sheets." This new A.7 also includes the techniques from the previous B.1 ("Separate content and structure from presentation.") since this is one of the three overarching themes of section A.
  8. The previous E.1 ("Use only elements or attributes in a W3C HTML Recommendation (2.0 or higher) and style rules in a W3C CSS Recommendation.") became C.1 ("Wherever possible, only use presentation features defined in a W3C final specification.") which now incorporates the idea of other types of formats used on the Web such as PDF and Shockwave. It also has a new technique, "5. Avoid deprecated elements whenever possible. [Priority 2]"
  9. The following technique (A.8.2) was changed from a questionable priority 1, to a 2. ("Provide a mechanism to allow users to freeze movement or updating in applets and scripts or use style sheets and scripting to create movemnt.") This is because we already require that applets and scripts have alternative text and a description (if needed) as well as an alternative way of achieving the same function. (if needed and possible). Therefore, when scripts or applets are not loaded an accessible alternative will be available. However, it would be very good to make the applet or script directly accessible. It would be good to make applets and scripts directly accessible. The majority of our users either do not have the option to load applets or scripts in the first place, or have not been loading them because they are generally not accessible, at this point we are pushing for the alternative presentations rather than the direct access. Thus the Priority 2 rating.
  10. The previous A.6 and B.4 have been combined into the new A.6. "Ensure that text and graphics are perceivable and understandable when viewed without color."
  11. The previous C.1, now A.10 was extensively reworked to include more information about techniques.
  12. A new technique was added to the previous C.3 (now A.13), "For all form controls with labels, ensure that the label that is either: [Priority 2]
  13. The previous D.2 ("Mark up abbreviations and acronyms appropriately") has been combined with the previous B.5 ("Changes in language within text should be identified. (Text presented in another language should be clearly marked.") to create a new A.9. "Provide supplemental information needed to pronounce or interpret abbreviated or foreign text."
  14. The Good Design Practices from the previous Public Working Draft have been included as Priority 3's in section C.
  15. A short list of definitions have been included at the end.
  16. Links to the techniques document are no longer broken.

Copyright  ©  1997 W3C (MIT, INRIA, Keio ), All Rights Reserved. W3C liability, trademark, document use and software licensing rules apply. Your interactions with this site are in accordance with our public and Member privacy statements.