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Re: Table SUMMARY Tag

for

From: Jukka K. Korpela
Date: Mar 2, 2011 11:09AM

ejp10 wrote:

> Due to the various legal issues, our university is looking to improve
> implementation of accessibility.

Does the applicable legislation say something about SUMMARY attributes? (It
might, probably indirectly, by normatively referring to specifications that
discuss it.)

> One suggestion I have heard is to include a SUMMARY attribute for
> every HTML table, but I am seeing conflicting information about it.

There are indeed conflicts, but it would certainly be wrong to say that
_every_ table must have a SUMMARY attribute. WCAG 2.0 tech document
http://www.w3.org/TR/WCAG-TECHS/H73.html clearly says that layout tables
should _not_ have a SUMMARY attribute or should at most have an empty
SUMMARY attribute (summary=""). It also describes the attribute as something
needed for _complex_ tables.

> Some sources say the summary is to summarize trends in the data, but
> others say it is to specify table structure (although I thought the
> CAPTION tag and the SCOPE/headers tags dis that as well.

This is a somewhat obscure area, and I would say that if the attribute is
used, its value should be such that it is useful to a person who does not
see the table as a whole but needs to process it sequentially or by
accessing cells by column and row headings or numbers. What this implies
depends on the context and structure.

On the other hand, the HTML5 drafts designate the SUMMARY attribute as
obsolete and declare that authors must not use it. Whatever we think of
HTML5, it seems to be the way the world is going. I guess the reason for
making SUMMARY as obsolete is twofold: first, it has fairly limited support
and usage; second, it is better replaced by explanations that every user can
make use of.

--
Yucca, http://www.cs.tut.fi/~jkorpela/