Collaborative Environments: Accessibility and Usability for Users with Special Needs - Community-Built Databases: Research and Development - page 326

Since 1999 the W3C has proposed different guidelines for developing accessible
Web environments and at least two approaches have been identified to guarantee
their accessibility. The first one is rather technical and defines guidelines and
checklists to be satisfied in order to accomplish the accessibility of user interfaces;
the second one is more user centered and also considers the user experience while
browsing the Web. In the following, we will briefly introduce the initiatives
promoted by the W3C to cope with Web accessibility.
Accessibility 1.0 . European national laws such as the Italian Law n. 4/2004 on
Web Accessibility, the German Federal Ordinance on Barrier-Free Information
Technology, and the French General Reference for Accessibility of Administra-
tions are based on the technical approach providing sets of technical requirements
to be checked in the spirit of the guidelines proposed by the W3C: the Web
Content Accessibility Guidelines (WCAG 1.0) [ 34 ], the Authoring Tools Acces-
sibility Guidelines (ATAG 1.0) [ 35 ], the User Agent Accessibility Guidelines
(UAAG 1.0) [ 36 ].
These guidelines explain how to make Web content accessible and are intended
for all Web content developers (page authors and site designers) and for developers
of authoring tools. Consider for example WCAG 1.0. The first guideline explains
how to introduce accessible images by providing equivalent alternatives to non-
textual content. The second one emphasizes that content, error messages, or possi-
ble actions should not rely only on colors, so that visually impaired or color-blind
users can also easily understand them. Moreover, clear navigation mechanisms
(guideline 13) and clear and simple documents (guideline 14) are fundamental for
people with visual or cognitive impairments.
WCAG 1.0 has been acknowledged by different governments in Europe and the
USA 1 because of their relevance in providing the same right to all citizens to access
information. Moreover, many software tools [ 9 ] have been developed to be com-
pliant with the technical indications they contain, which are mostly based on HTML
markup and proper use of CSS properties.
The guidelines contained in ATAG 1.0 are specific for Web authoring tool
developers. Their purpose is “twofold: to assist developers in designing authoring
tools that produce accessible Web content and to assist developers in creating an
accessible authoring interface” [ 35 ]. Specifically, authoring tools should automati-
cally generate standard markup (guideline 2) and support the creation of accessible
content (guideline 3) facilitating for instance the insertion of text alternatives. A
peculiarity of these guidelines is the number 7, which also requires that authoring
interfaces should be accessible. This is particularly relevant in the collaborative
context since users with a disability are encouraged to become producers and
contributors of new knowledge.
Accessibility 2.0 . The W3C guidelines presented so far have been a reference for
many years. However, the technical approach on which they are based has been
deeply criticized by experts [ 3 , 19 ]. Indeed, a strict adherence to technical
1 An example is Section 508, http://www.section508.gov/