From http://www.w3schools.com (Copyright Refsnes Data)

Web Quality - Accessibility (WAI)

An accessible web site is a web site that can be used by disabled users.

Disabled users are users with disabilities or bad user conditions.

The Web Accessibility Initiative - WAI

WAI (created by the World Wide Web Consortium (W3C) in 1997) is a set of guidelines intended for web developers, authors, and designers- about how to make web content accessible to people with disabilities.

The goal of these guidelines is accessibility, but they will also help make web contents available to more browsers (voice browsers, cell phones, hand-held devices), and to more users working in difficult environments (hands-free, strong light, darkness, bad sight, heavy noise).

Is WAI Important to Your Web Site?

Yes it is.

Millions of people with disabilities are surfing the Internet every day, and even more millions are using poor browser equipment, or working under difficult user environments.

If your website lacks features such as resizable fonts, images with proper text descriptions, and easy navigation, these people will not be able to access your information.

In fact: Your site violates the rights of these people.

Here are some other reasons for making your site more accessible:

It will improve your reputation and image
It will improve your customer satisfaction
It will increase your number of visitors
It will let your visitors stay longer at your site
It will increase the number of returning visitors
It will make your site more usable also for people with no disabilities
It will make your site more usable for users with images turned off
It will make your site more usable for people with older equipment
It will let you reach the fastest growing population: older people

Use an Adjustable Font Size

Use only relative font sizes, and let the user be able to use the browser menu (View - Text Size) to change the default text size.

Can you read this?

To change the font size, select view - text size - in your browsers menu.

Use The "alt" Attribute

The alt attribute allows you to provide a text equivalent for an image (and for some other elements).

Example:

<img src="images/bana.jpg" alt="Banana" />

Sometimes a web browser will not display your images. The reason could be one of many:

The user has turned off the display of images
The browser is a mini browser without image display.
The browser is a voice browser (used by blind or poor-sighted)

If you use the "alt" attribute, most browsers will at least display or read the "alt" description.