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Universally Accessible Web Resources: Designing
for People with Disabilities
Universally Accessible Web Resources: Designing
for People with Disabilities
Jon Gunderson,University of Illinois at Urbana–ChampaignIntroduction 477
Myths of the Web 477
Digital Divide 477
Alternative Views of the Web 478
Keyboard Support 478
Access to Text Descriptions 479
User Styling of Text 482
Speech Browsing 482
Web Design Guidelines 484
W3C Web Content Accessibility Guidelines 484
WCAG Priorities and Conformance 484
WCAG Guidelines 484
WCAG 2.0 Development 486
U.S. Section 508 Requirements 486Evaluation and Repair Tools 487
HTML Validation 487
Evaluation Tools 487
Evaluation and Repair 489
Limitations of Current Authoring Tools 489
Microsoft Power Point Accessibility Plug-in 490
Accessible Repair or Universal Design? 490
Laws and Regulations 491
Conclusion 492
Glossary 492
Cross References 492
References 492
Further Reading 493INTRODUCTION
Tim Berners Lee developed the first HTML (hypertext
markup language) Web browser/editor in 1990 to enable
scientists at the CERN particle physics lab in Switzerland
to share electronic documents on a wide range of com-
puting systems. At the heart of the design of HTML tech-
nologies is the concept of interoperability, the ability of
providing and receiving electronic documents using pub-
lic standards for creating, serving, and viewing the infor-
mation on a wide variety of computing equipment. In the
beginning the focus was on the information. Users typ-
ically had a wide range of choices and control over the
rendering of Web documents. Authors were not very in-
terested in controlling the rendering of HTML and indeed
HTML has limited features for absolute control over ren-
dering.MYTHS OF THE WEB
As the Web was commercialized through the introduction
of graphical browsers (NCSA Mosaic, Netscape Navigator,
and Microsoft Internet Explorer) in the mid- to late 1990s
there was a fundamental change in the relationship be-
tween the control authors had over the rendering style of
Web resources and the users’ ability to control the render-
ing. There are many reasons for this shift, but the result
is that the vast majority of Web authors developing com-
mercial content primarily think of the Web as a graphical
medium. At the same time the most popular commercial
browser developers provided users with fewer and feweroptions for adjusting the rendering of Web resources to
a point where most users today do not know they have
any control over the rendering of Web content, and this
reinforces the beliefs of the Web as a graphical medium
in which users have no control over rendering. This has
lead to the design of inaccessible Web resources that
increasingly only support graphical renderings and the
use of pointing devices (e.g., the mouse) for interacting
with dynamic content. An example of this narrowing view
of interoperability is many developers requiring their Web
pages appear visually the same in both Netscape Naviga-
tor 4.7 and Internet Explorer 4.0+even though Netscape
Navigator 4.7 is an outdated technology that does not con-
form to HTML 4.0 or 3.2 specifications (CITA Surveys,
2001a, 2001b). This approach leads developers to use im-
ages and complex table layouts for styling and positioning
text and images, giving users little opportunity to access
the content in non-graphical renderings of text, Braille, or
speech.DIGITAL DIVIDE
The divide between people with visual impairments and
able-bodied Web users was investigated by Pernice-Coyne
and Nielsen (2001). They found that people who use
screen magnification technologies could only complete
Web tasks about 21% of the time and people using speech
output about 12.5% of the time. When compared to the
able-bodied control group performance of completing
tasks about 78% of the time, it is clear that current Web
design is creating tremendous barriers to people with477