abbr-design-pattern
<entry-title> abbr design pattern </entry-title>
Purpose
Use the abbr-design-pattern when you have localized, language, or design-specific human readable information that you want to markup and also provide a more globally human and machine readable alternative.
- Authors MUST NOT use the abbr-design-pattern to re-encode human text or to hide data
- The contents of the
<abbr>tag'stitleattribute MUST be both human-readable and human-listenable (e.g. for screenreaders), and SHOULD use a globally/internally human readable format. - For dates and times authors SHOULD use the HTML5
<time> element instead of<abbr>. (ed: Once common tools like chrome-extensions, h2vx, operator all support the HTML5 time element, let's upgrade this statement to a {{{must}}}).
How to use it
- enclose the preferred local human readable text that you want to make globally human & machine readable with
<abbr>
- add the relevant microformats property names to the
<abbr> tag's class attribute
- add a
title attribute to the abbr element with the globally human & machine readable data as the value
- The end result MUST be human readable & listenable, when reading/speaking the abbr element's contents and its surroundings and when reading/speaking the abbr element's title attribute with its surrounding text.
Example
The date-design-pattern formally encodes globally human readable ISO dates into an abbr element. Per the documentation/research on the date-design-pattern page, ISO8601 dates, e.g. of the form YYYY-MM-DD, are the most globally/internationally date format.
Note: that dates and times SHOULD be marked up with the HTML5 time element. These examples illustrate both span/abbr markup for pre-HTML5 tools, and time element support for HTML5-capable tools.
Before:
The party is on the 10th.
After:
The party</span> is on
<abbr class="dtstart" title="2005-10-10">the 10th</abbr>.
Better (with HTML5 time instead of abbr)
The party is on
<time class="dtstart" datetime="2005-10-10">the 10th</time>.
You could also use the abbr-design-pattern to markup colloquial time references, but those should also use the HTML5 time element
Before:
The party is at 10 o'clock.
After:
The party is at <abbr class="dtstart" title="10:00">10 o'clock</abbr>.
Better (with HTML5 time instead of abbr)
The party is at <time class="dtstart" datetime="10:00">10 o'clock</abbr>.
Alternative presentations
Note that the following are all equivalent, to a microformat parser:
<span class="dtstart">2007-05-01</span>
<abbr class="dtstart" title="2007-05-01">1 May 2007</abbr>
<abbr class="dtstart" title="2007-05-01">1st May 2007</abbr>.
<abbr class="dtstart" title="2007-05-01">May 1st 2007</abbr>.
<abbr class="dtstart" title="2007-05-01">The first of May, 2007</abbr>.
<abbr class="dtstart" title="2007-05-01">2007-05-01</abbr>.
<abbr class="dtstart" title="2007-05-01">Tuesday, 1 May 2007</abbr>
<abbr class="dtstart" title="2007-05-01">2007, day 121</abbr>
<abbr class="dtstart" title="2007-05-01">May Day, 2007</abbr>
<abbr class="dtstart" title="2007-05-01" lang="FR">1er mai, 2007</abbr>
<abbr class="dtstart" title="2007-05-01" lang="ES">1 de mayo, 2007</abbr>
and the following may be used in, say, a list, table, or page, headed "2007":
<abbr class="dtstart" title="2007-05-01">1 May</abbr>
Better (with HTML5 time element)
<time class="dtstart">2007-05-01</time>
<time class="dtstart" datetime="2007-05-01">1 May 2007</time>
<time class="dtstart" datetime="2007-05-01">1st May 2007</time>.
<time class="dtstart" datetime="2007-05-01">May 1st 2007</time>.
<time class="dtstart" datetime="2007-05-01">The first of May, 2007</time>.
<time class="dtstart" datetime="2007-05-01">2007-05-01</time>.
<time class="dtstart" datetime="2007-05-01">Tuesday, 1 May 2007</time>
<time class="dtstart" datetime="2007-05-01">2007, day 121</time>
<time class="dtstart" datetime="2007-05-01">May Day, 2007</time>
<time class="dtstart" datetime="2007-05-01" lang="FR">1er mai, 2007</time>
<time class="dtstart" datetime="2007-05-01" lang="ES">1 de mayo, 2007</time>
<abbr class="dtstart" datetime="2007-05-01">1 May</abbr>
anti-patterns
These are all past examples that are usages to avoid.
Authors MUST NOT use the abbr element as shown in these examples, as either the element text or the title attribute text are not easily human readable.
<span class="dtstart">20070501</span>
<abbr class="dtstart" title="20070501">1 May 2007</abbr>
<abbr class="dtstart" title="20070501">1st May 2007</abbr>.
<abbr class="dtstart" title="20070501">May 1st 2007</abbr>.
<abbr class="dtstart" title="20070501">The first of May, 2007</abbr>.
<abbr class="dtstart" title="20070501">2007-05-01</abbr>.
<abbr class="dtstart" title="20070501">Tuesday, 1 May 2007</abbr>
<abbr class="dtstart" title="20070501">2007, day 121</abbr>
<abbr class="dtstart" title="20070501">May Day, 2007</abbr>
<abbr class="dtstart" title="20070501" lang="FR">1er mai, 2007</abbr>
<abbr class="dtstart" title="20070501" lang="ES">1 de mayo, 2007</abbr>
<abbr class="dtstart" title="20070501">1 May</abbr>
<!-- lack of dashes in "20070501" reads like a large number, not a date -->
Discussion
about datetimes
Avoid using the abbr-design-pattern for datetimes.
E.g. Authors MUST avoid doing this:
<abbr class="dtstart" title="20051012T11:10-0100">10 past 11 o'clock on the 12th</abbr>
Ideally use the HTML5 time element:
<time class="dtstart" datetime="2005-10-12T11:10-0100">10 past 11 o'clock on the 12th</time>
Note the use of the hyphenated date to make it more human readable, as the more readable that even machine data is made, the greater the chance that a human will be able to accurately check it and verify that it matches the locale/language-specific contents of the time element.
Alternatively, if the microformats tools you're using don't support HTML5 (yet), you may use the value-class-pattern with the abbr-design-pattern:
<span class="dtstart">
<abbr class="value" title="11:10">10 past 11 o'clock</abbr> on
<abbr class="value" title="2005-10-10">the 10th</abbr>
</span>
informal names
Using ABBR to encode more formal human data around something less formal:
<abbr class="author" title="Danny Ayers">Danny</abbr>
This use is discouraged under the Don't Repeat Yourself principle, as it is a case of *more* information being less visibly present, namely,
the last name in this case.
If someone is not willing to make some information visible, then we
shouldn't be encouraging them to store that information invisibly or less visibly,
for all the same reasons that invisible metadata is bad/futile in the first place."
screen readers
The title attribute of the <abbr> tag MUST always be human readable and speakable.
Screenreaders such as JAWS and others which use title attributes from abbr, and when used properly (as in this example below from the WCAG group), pronounce words which would otherwise be unreadable or confusing.
<p>Sugar is commonly sold in 5 <abbr title="pound">lb.<abbr> bags.</p>
<p>Welcome to the <abbr title="World Wide Web">WWW</abbr>!</p>
If screen readers are unable to turn title content into something comprehensible, this will lead to accessibility failures. Here is a bad example:
we have a party in
<abbr class="dtstart" title="20070312T1700-06">
March 12, 2007 at 5 PM
</abbr>
would be read by Jaws as
we have a party at Twenty million seventy-thousand three-hundred twelve tee seventeen-hundred dash zero six.
The accessibility task force from webstandards.org recommended:
<span class="dtstart" title="20070312T1700-06">
March 12, 2007 at 5 PM, Central Standard Time
</span>
or
<source lang=html4strict>
March 12, 2007 at 5 PM, Central Standard Time
But this approach is problematic due to the unhyphenated date and combined datetime in the title attribute being not easily human readable/verifiable.
However, based on this input and subsequent research into better alternatives, the microformats community developed the value-class-pattern :
(to be filled in)
See Also