Technique H73:Using the summary attribute of the table element to give an overview of data tables
Applicability
HTML 4.01, XHTML 1.x
This technique is not referenced from any Understanding document.
Description
The objective of this technique is to provide a brief overview of how data has been
organized into a table or a brief explanation of how to navigate the table. The summary
attribute of the table
element makes this information available to people who use screen readers; the information
is not displayed visually.
The summary
is useful when the table has a complex structure (for example,
when there are several sets of row or column headers, or when there are multiple groups
of columns or rows). The summary
may also be helpful for simple data tables
that contain many columns or rows of data.
The summary
attribute may be used whether or not the table includes a
caption
element. If both are used, the summary
should not
duplicate the caption
.
In HTML5 the summary
attribute is obsolete. Assistive technologies may or may not continue to support
the attribute. Authors should consider alternatives and only use with caution.
Although WCAG 2 does not prohibit the use of layout tables, CSS-based layouts are
recommended in order to retain the defined semantic meaning of the HTML table
elements and to conform to the coding practice of separating presentation from content.
However, if a layout table is used, then the summary
attribute is not used or
is null. The purpose of a layout table is simply to control the placement of content;
the table itself is “transparent" to the user. A summary
would “break" this
transparency by calling attention to the table. A null summary
(summary
="") on layout tables is acceptable. See F46 for details.
Examples
Other sources
No endorsement implied.
- HTML 4.01 summary attribute
Tests
Procedure
For each data table:
- If a
summary
is present, check that thesummary
attribute describes the table's organization or explains how to use the table - If both a
summary
attribute and acaption
element are present for the data table, check that thesummary
does not duplicate thecaption
.
Expected Results
- #1 and #2 are true.