An Introduction To Accessible Web Design

Posted on: 30 April 2003 (Originally published 23rd November 2002 on SitePoint)

Accessibility in Web Design addresses the issue of creating Web sites that are accessible to all users, regardless of physical ability or the way in which they are using the Internet.

In this article I will be introducing the concepts surrounding accessible Web Design, the current initiatives to increase the accessibility of Web sites and the guidelines that you can use to make your site more accessible.

Why Accessibility Is Important

Why aren't all Web sites accessible? You may be asking yourself why this issue exists and why all Web sites aren't already accessible to all users. There are a number of reasons that I will outline now.

Visually Disabled Users

Visually disabled users ranging from colour blind to fully blind have problems with images that do not provide a text description of what they show. Without a text description a user who can't see an image has no way of knowing what it is or what it represents.

These users also have problems understanding sites that are not logically built when "viewed" using a non-visual browser such as a screen reader. A screen reader is a Web Browser that reads Web sites out loud so as to make them accessible to visually disabled users. Often a Web site that looks nice visually will be a complete mess when it is listened to through a screen reader.

Hearing Disabilities

In a similar way to visually disabled users not having any way of understanding an image, users with hearing disabilities have no way of understanding information that is communicated with sound, unless an alternative is provided that does not use sound, such as a text description or an image.

Physical Disabilities

If you are not physically disabled, have you tried using a Web site without your mouse? Unless you were lucky with the site you chose then you probably found it very difficult. Physically disabled users are often incapable of using a mouse. Unless these users needs are taken into account when creating Web site navigation and input methods physically disabled users will sometimes find a Web site completely inaccessible.

Cognitive and Neurological Disabilities

Web sites can be complex, and finding the information we want can be difficult for the most able of us. This is not helped by sites that use an overly complex design, navigation that works differently on different pages (inconsistent) and distracting repetitive animation. All of these problems are compounded for users with Cognitive and Neurological Disabilities and this makes some sites completely inaccessible for them.

Beyond Disabilities

As we have seen, using the Internet if you have a disability can be a difficult task. By observing and understanding the guidelines for accessible Web Design a site can be produced that serves it's purpose and is accessible to all of it's users, not just those without disabilities.

But it doesn't stop there. Accessible Web Design has benefits for other users too. Let's see who else can benefit.

The following groups will benefit from following the guidelines for making your site accessible:

  • Users of mobile phones, Web-TV and kiosks,
  • Low bandwidth users,
  • Users in a noisy environment,
  • Users with "screen glare",
  • Users who are driving,
  • Users with a low literacy level,
  • Second-language access and
  • Users with different learning styles.

Dealing with accessibility issues also improves:

  • Page transmission and site maintenance,
  • Machine indexing of content and
  • Searching of content.

The Marketplace

There's another reason for making your site accessible (if you need any more). According to current figures disabled users currently make up around 10% to 20% of the population in most countries. Increase that for the amount of your users who fall into the categories listed above and you're looking at up to 30% of the market. If making your site accessible to 30% of the market doesn't persuade you that accessible Web Design is worth it then stop reading now.

The average age of the population in many countries is also increasing. Aging results in a number of accessibility issues including vision and hearing changes and changes in dexterity and memory. If your market includes a significant number of elderly users then you can increase that 30% to a much larger percentage of users who will reap the benefits of accessible Web Design.

Legal Requirement

For certain Web sites, addressing accessibility can be a legal requirement. This is usually for government sites but can affect others. For more information on the requirements in different countries see the W3C page Policies Relating to Web Accessibility.

Part two - Accessibility Initiatives >>