Web
Accessibility: The Basics
by © Trenton Moss
What is web accessibility & why is
it important?
Web accessibility is about making your
website accessible to all Internet users (both disabled and non-disabled),
regardless of what browsing technology they're using. In addition to complying
with the law, an accessible website can reap huge benefits on to your website
and your business.
Your website must be able to function with
all different browsing technologies
The first and perhaps the most important
rule of web accessibility. Not everyone is using the latest version of
Internet Explorer, with all the plug-ins and programs that you may require
them to have for your website. Different browsing technologies, each with
their own accessibility requirements, can include:
-
Lynx browser - Text-only browser with no support
for tables, CSS, images, JavaScript, Flash or audio and video content
-
WebTV - 560px in width with horizontal scrolling
not available
-
Screen reader - Page content read aloud in
the order it appears in the HTML document
-
Handheld device - Very small screen with limited
support for JavaScript and large images
-
Screen magnifier - As few as three to four
words may be able to appear on the screen at any one time
-
Slow connection (below 56kb) - Users may turn
off images to enable a faster download time
-
1600px screen width - Very wide screen
This basically means that to ensure your website
is accessible to everyone you must provide alternatives to:
-
Images - in the form of ALT text
-
JavaScript - through the tag
-
Flash - with HTML equivalents
-
Audio & video - by using subtitles or
written transcripts
-
For enhanced website accessibility you must
also be careful how your pages look when support for CSS and/or tables
has been removed.
There are two good ways you can check your
website is accessible for all these:
Forms need to be accessible to all web users
When a web user fills out a form it's a
great thing. People fill out forms to:
-
Buy a product
-
Sign up to a newsletter
-
Ask a question
These are the goals of your website! A site
visitor may look through your site, decides he likes what he sees and tries
to sign up to your newsletter.
...But the form isn't accessible to him
so he clicks away and you lose a potential customer. Most forms on the
web suffer from accessibility issues. The two main reasons for this are:
-
Prompt text is incorrectly positioned
-
Prompt text is unassigned to form items
(Prompt text is the text that appears next
to each form item, for example, �name�, �e-mail�, �comments�)
To find out more please read this article
about making your forms accessible (http://www.sitepoint.com/article/accessible-online-forms).
It should be easy for all users to quickly
process the content on your website
We generally don't read web pages. We scan,
trying to find what we're looking for as quickly as possible. On a regular
monitor, we scroll down the page looking at the items that stand out from
the rest of the text: headings, links, bold text and bullet points. Non-keyboard
and visually impaired users often scan pages by tabbing between headings
or links.
To ensure the accessibility of your website,
use headings, links, bold text and bullet points and make sure they contain
descriptive text. For example, never use 'click here' for link text.
Structure and presentation should be completely
separated
By separating structure and presentation
your website will be accessible to and ready for the future of the Internet:
PDAs, mobile phones, in-car browsers, WebTV and 1600px screens.
The structure of a document is how it is
organised, usually with navigational menu items, headings, sub-headings,
paragraphs, lists, and links. The presentation of a document is how these
words and images are presented to the end user.
The main principle behind this accessibility
guideline is to use CSS and not tables to lay out your web pages. Check
out our CSS resources area for how to use CSS to increase your website's
accessibility.
There's more to separating structure and
presentation than just laying your web pages out with CSS. Have a look
at this HTML element list that tells you which elements are structural
and which are presentational. For optimal web accessibility, you can, and
should, avoid using presentational elements as they may cause your website
to become less accessible to certain users.
The end user should have control over your
web pages
All web users have unique requirements
for how they use the Internet, depending on the kind of browser they're
using or any kind of handicap or disability they may have. By handing control
back to your users you'll enhance your website's accessibility and you
site visitors will be able to use your website in the way that best suits
them.
This accessibility guideline could mean
allowing users to resize text, warning them when links are going to open
in a new window, or providing a link at the top of the screen that takes
the user directly to the page content.
About the Author:
-----------------------
Copyright © Trenton Moss
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.
| 
