Web Design

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Understanding Web Accessibility .............................

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usinesses, generally speaking, do not like to turn away potential customers. However, many do

just that on their Web sites when they fail to recognize that significant numbers of users may

have disabilities that limit their ability to navigate the Web in the ways that nondisabled users can.

Navigation that can be accessed only with a mouse, video or audio content without captioning,

needlessly complex layouts, and nonsemantic markup all pose challenges to disabled users. Ignoring

accessibility on your Web site can at least drive away customers, and may subject you to legal penalties.

Visual Impairment

Because the Web is a primarily visual medium, visual impairment is perhaps the most important disability to

consider when building your site. From total blindness to very poor eyesight, those with visual impairments

use software applications called screen readers to navigate on their computers. Visually impaired users rely

almost exclusively on their keyboards to navigate within their machine because they obviously cannot use a

mouse or other pointer device.

Hearing Impairment

Hearing disabilities, of course, become an issue only if your site contains audio content, usually in videos.

You need to ensure that any content delivered through audio channels is also available in a nonaudio

format, either through closed captioning or similar technologies or through a text transcript of the audio.

Color Blindness

A very significant percentage of people, mostly men, suffer from some degree of color blindness. Although

extreme cases involve the complete inability to see color, most people suffer from some lesser degree of

color blindness whereby they are simply unable to distinguish between certain shades of color, or even see

differences between colors if they lack sufficient contrast.

Cognitive Disabilities

Those with cognitive disabilities, such as learning disorders or dyslexia, will have a difficult time

understanding your site’s content unless you take these disabilities into consideration and create content

that can be easily understood.

Mobility Impairment

Although a lot of Web professionals now understand, and take into consideration, visual impairment, many

still ignore mobility impairments. They mistakenly believe that as long as a person can see, they can use

any Web site. However, many people with mobility impairments lack the full use of their hands, which in

turn means that they cannot use a mouse.