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The Secret Benefit Of Accessibility Part 2 A Higher Search Engine Ranking
n additional benefit of engines can't understand images
website accessibility is an either and won't take any meaning
improved performance in from them. Many search engines
search engines. The more can now index ALT text though, so
accessible it is to search by assigning ALT text search
engines, the more accurately they engines will be able to
can predict what the site's understand all your images.
about, and the higher your site
will appear in the rankings. 2. Text displayed through HTML,
not images
Not all of the accessibility
guidelines will help with your Text embedded in images appears
search engine rankings, but there pixelated, blurry and often
are certainly numerous areas of impossible to read for users
overlap: utilising screen magnifiers. From
an accessibility point of view
1. ALT descriptions assigned to this should therefore be avoided.
images
Search engines equally can't read
Screen readers, used by many text embedded in images. Well,
visually impaired web users to you can just give the image some
surf the web, can't understand ALT text, right? Unfortunately,
images. As such, to ensure there's strong evidence to
accessibility an alternative suggest search engines assign
description needs to be assigned less importance to ALT text than
to every image and the screen they do to regular text. Why?
reader will read out this Spammers. So many webmasters have
alternative, or ALT, description. been stuffing their ALT tags full
of keywords and not using them to
Like screen readers, search describe the image. Search
engines have cottoned on to this is about.
form of spamming (as they
eventually do every form of One of the best examples of this
spamming) and have taken in action is for the search term,
appropriate action. ‘miserable failure'. So many
people have linked to George
3. Descriptive link text Bush's bio using this phrase as
the link text, that now when
Visually impaired web users can miserable failure is searched for
scan web pages by tabbing from in Google, George Bush's bio
link to link and listening to the appears top of the search
content of the link text. As rankings!
such, the link text in an
accessible website must always be 4. Website functions with
descriptive of its destination. JavaScript disabled
Search engines place a lot of JavaScript is unsupported by
importance on link text too. They about 9% of web users (source:
assume that link text will be http://www.thecounter.com/stats/2
descriptive of its destination 004/November/javas.php), either
and as such examine link text for because they've turned it off
all links pointing to any page. (for example to prevent pop-up
If all the links pointing to a adverts) or because their browser
page about widgets say ‘click doesn't support it. Many forms of
here', search engines can't gain JavaScript aren't accessible to
any information about that page web users utilising screen
without visiting it. If on the readers.
other hand, all the links say,
‘widgets' then search engines Search engines can't understand
can easily guess what that page JavaScript either and will be
unable to index any transcripts provide them with a
JavaScript-driven content. large amount of text for them to
Perhaps more importantly, they'll index.
also be unable to follow
JavaScript-driven links. You may 7. Site map provided
really like the look of your
dropdown menu but search engines Site maps can be a useful tool
won't if they can't access for visually impaired users as
certain pages on your site they provide a straightforward
because there aren't any regular list of links to the main pages
links pointing at them. on the site, without any of the
fluff in between.
5. Alternatives to Flash-based
content provided Site maps are also great for
search engines as search engines
Flash, like JavaScript, isn't can instantly index your entire
accessible to many users, site when they arrive at the site
including those using screen map it. Next to each link you can
readers. Equally, search engines also provide a short keyword-rich
can't access Flash so be sure to preview of the page. All links
provide equivalents. should, of course, be made
through regular HTML and not
6. Transcripts available for through JavaScript (see 4.
audio above).
Hearing impaired users obviously 8. Meaningful page title
require written equivalents for
audio content to be able to When we arrive at web pages the
access it. Search engines too first thing that appears, and the
can't access this medium, but first thing that visually
impaired users hear, is the page h2 etc.
title. This latter group of web
users don't have the privilege of Search engines assume that the
being able to quickly scan the text contained in heading tags is
page to see if it contains the more important than the rest of
information they're after, so the document text, as headings
it's essential that the page describe the content immediately
title effectively describes the below them. Make sure you use the
page content. heading tags properly and don't
abuse them, as the more text you
If you know anything about search have contained in heading tags,
engine optimisation you'll know for example, the less importance
that the page title is the most search engines assign to them.
important attribute on the page.
If it adequately describes the 10. CSS used for layout
content of that page then search
engines will be able to more Screen readers can more
accurately guess what that page effectively work through the HTML
is about. code of CSS-based sites as
there's a greater ratio of
9. Headings and sub-headings used content to code. Websites using
CSS for layout can also be made
Visually impaired web users can accessible to in-car browsers,
scan web pages by tabbing from WebTV and PDAs. Don't
heading to heading, in addition underestimate the importance of
to tabbing from link to link (see this - in 2008 alone there'll be
3. above). As such, it's an estimated 58 million PDAs sold
important for accessibility to worldwide (source:
make sure that headings are http://www.etforecasts.com/pr/pr0
correctly marked up by using h1, 603.htm).
Search engines also prefer Conclusion
CSS-based sites and are likely to
score them higher in the search With all this overlap between web
rankings because: accessibility and search engine
optimisation there's no excuses
- The code is cleaner and for not implementing basic
therefore more accessible to accessibility on to your website.
search engines It'll give you a higher search
- Important content can be placed engine ranking and therefore more
at the top of the HTML document site visitors.
- There is a greater density of
content compared to coding
About the Author:
This article was written by Trenton Moss. He's crazy about web usability and accessibility - so crazy that he went and started his own web usability and accessibility consultancy ( Webcredible - http://www.webcredible.co.uk ) to help make the Internet a better place for everyone.
Read more articles by: Trenton Moss
Article Source: www.iSnare.com
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