Proposed approaches in defining the summary attribute

The summary attribute version a

The summary attribute represents a prose summary of the table's structure, primarily for user agents rendering to non-visual media such as speech and Braille. The value is text.

The primary purpose of the summary attribute is to provide guidance to people with vision impairments on how to read a table, where the structure and reading order is visually evident, but not available to some assistive technology users.

The summary attribute may be set on the table element if the data it contains is of sufficient complexity that users of non-visual user agents would benefit from a prose description of the table's structure. If the table contains data considered to only require a short description, use the caption element. Do not repeat the content of the caption element as content in the summary attribute.

The attribute may only be set on tables that contain tabular data. The attribute must not be set on tables used for layout purposes. The attribute should not be set to the empty string.

Any user agent may provide a mechanism to access the summary attribute content. If the mechanism provides the summary content as conditional content it must be input device independent.

The summary DOM attribute must reflect the summary content attribute.

Notes version a

• This is a first attempt at defining the summary attribute in HTML 5.
• Please feel free to comment on ways the definition can be improved.
  • Comments:
    1. Please consider adding more author guidance regarding how to use summary correctly so that more authors use it right. And discourage inappropriately use of summary - Laura Carlson
    2. Some confusion has existed in the past as to the length of a table summary. Is a summary's purpose in version "a" to provide an overview of how data has been organized into a table or a brief explanation of complex data table as stated in WCAG2's H73 or is it to provide a long description as stated in HTML 4? Please consider adding an adjective or sentence to clear up this ongoing historical ambiguity as to concise overview or long description. Also see Purpose of the summary Attribute by Gez Lemon- LauraCarlson
    3. @summary can be used as a general "heads up" to a blind user about the nature of the table as well as it more strict use as an outline of content and their relationship. So maybe there is a need to state that there should be some flexibility in how the @summary is described. - Joshue O Connor
• It is intended that usage examples be added.
  • Possible Examples:
    1. H73: Using the summary attribute of the table element to give an overview of data tables - Technique for WCAG 2.0
    2. Blind/Non-Visual and Sighted Use Cases
    3. Example of complex data organized under second logical level (running costs)
• If you wish to modify the definition text please create a new version and add it under the other versions or on a new page.

The summary attribute version b

The summary attribute represents a prose overview or summary of the table's structure, primarily for user agents rendering to non-visual media such as speech and Braille. Authors and users however may use CSS and other styling mechanisms to present the contents of the summary in and around the table even for visual users. Implementations may also provide an inspector or some other user interface to display the contents of the summary attribute outside the normal flow of the document. The value of the summary attribute is text.

The primary purpose of the summary attribute is to provide guidance and an overview on how to consume the table for users with visual or cognitive impairments. Especially for complex tables where the structure and reading order is visually evident, the lack of a summary overview hinders those users consuming the table in a non-visual manner.

The summary attribute may be set on the table element if the data it contains is of sufficient complexity that users of non-visual user agents would benefit from a prose description of the table's structure. If the table is simple enough to not require a summary description of the table’s structure, authors may omit the summary attribute. Authors who are unfamiliar with the needs of non-visual users or who are unsure about the recommendations and requirements for authoring properly summary content should omit the attribute entirely.

Authors may use the caption element to provide a short description of the table’s purpose or a title for the table. If authors choose to not provide a caption for visual users, they should consider including a caption within the table’s caption element and use CSS to control the presentation for visual user agents so that captions are available to non-visual users. However, authors should not include a caption with the summary attribute and must not repeat the content of the caption element as content in the summary attribute. In general authors should treat the summary as alternate content directed specifically at visually, cognitively, and otherwise impaired users such as users of non-visual UAs.

The attribute may only appear on tables that contain tabular data. While authors should use tables only for tabular data, authors may use the role attribute with the keyword 'layout', if the author is unable to avoid the use of a layout table.

The summary DOM attribute must reflect the summary content attribute.

Notes version b

In relation to the issues to discuss section below this prose addresses those issues by:

• including cognitive disabilities in the users targeted by the 'summary' attribute mechanism
• When captions are not desirable for presentation to visual users, recommends using CSS to control the display of captions and discourages the authoring of 'summary' content with any caption at all (this is meant to address a common misuse of the 'summary' attribute for captions targeted only at non-visual users)
• recommends using the 'role' attribute to explicitly label layout tables and not null summary or summary keywords for such labeling

Issues for discussion

• Permit null 'summary' values on layout tables?
• How to provide captions for non-visual users when authors omit captions for visual users?
• Should summary be used for users with cognitive impairments or only those with visual impairments?
• Should the prose explicitly prohibit the use of keywords such as “navigation” and “layout” within the value of the 'summary' attribute?

See Also

• Mechanism to Summarize a Table
• Use cases for summarizing tables
• Diff between the original version A and version B
• F46: Failure of Success Criterion 1.3.1 due to using th elements, caption elements, or non-empty summary attributes in layout tables
• H73: Using the summary attribute of the table element to give an overview of data table
• WCAG 2.0 5.1.1 Providing summary information
• WCAG 2.0 Checkpoint 5.5 Provide summaries for tables