Introduction to Web Accessibility

Shadi Abou-Zahra, W3C/WAI
http://www.w3.org/People/shadi/

(alternate presentation format available)

Yesterday...

Old computer connected to the internet via an acoustic coupler to an analog telephone

...Today

Lecture room full of people using laptops, tablets, mobile phones, and other devices

...Tomorrow?

Four teenagers sitting in a cafe and each fully immersed in her mobile phone

One Web

Different mobile phones, computer screen, airlines entertainment system, car navigation system, ticketing machine, television, and a refrigerator with a built-in screen

The Open Web Platform

Illustration of devices and domains sorrounding the Open Web Platform described at http://www.w3.org/standards/

HTML5

HTML5 Logo

HTML5
...and Friends

Word cloud with HTML5, CSS, DOM, WCAG, WAI-ARIA, SVG, RDF, and many more

Web Technology Stack

Full W3C technology stack described at http://www.w3.org/Consortium/techstack-desc.html

Accessibility at W3C

The power of the Web is in its universality. Access by everyone regardless of disability is an essential aspect. - Tim Berners-Lee, W3C Director and inventor of the World Wide Web, 1997

Components of Web Accessibility

The Web consists of several components that work together:

Content - websites, web applications, documents, ...
Browsers - media players, assistive technology, ...
Authoring Tools - content management systems, ...
Technologies - HTML, CSS, XML, SVG, SMIL, ...

The Big Picture

What is Web Content Anyway?

different compents of a Web page such as pictures, text, diagrams, structures, etc.

Any information on your website and applications, including:

natural information such as text, images, and sounds
code or markup that defines structure, presentation, etc.

WCAG

Web Content Accessibility Guidelines (WCAG) 2.0
Internationally recognized standard for web accessibility:

Agnostic to any particular technology
Requirements are testable statements
Applies to web applications, mobile, TV, ...
Provides more support for developers

Web User Perspective

Web user with a symbolic path to represent Web content that passes through user agents and assistive technologies in order to be acquired or experienced information.

UAAG

User Agent Accessibility Guidelines (UAAG):

Access to all content, including content tied to events triggered by the mouse or keyboard
User control over how content is rendered
User control over the user interface, with documentation of accessibility features
Standard programming interfaces, to enable interaction with assistive technologies

Web Developer Perspective

Web developer with a symbolic path to represent information that passes through authoring tools and evaluation tools in order to be published Web content.

ATAG

Authoring Tool Accessibility Guidelines (ATAG):

Producing content that is accessible for people with disabilities
Prompting the author for accessibility-related information
Providing ways of checking and correcting inaccessible content
Integrating accessibility in the overall "look and feel," help, and documentation
Making the authoring tool itself accessible to people with disabilities

Dependencies Between Components

When Components Are Weak...

Symbolic paths around authoring tools or through multiple browsers and assistive technologies represent how Web developers and users need to spend more effort working around weak components that do not support accessibility.

Sometimes other components can compensate through "work-arounds"

require much more effort
not good solutions overall
often not implemented