This document discusses web accessibility and the Web Content Accessibility Guidelines (WCAG) 2.0. It notes that approximately 78 million people have disabilities and many use computers and the internet. However, 97% of websites are currently inaccessible. The four principles of WCAG 2.0 are described: perceivable, operable, understandable and robust. Guidelines around color contrast, images, headings and navigation are covered. Accessible Rich Internet Applications (ARIA), HTML5 and tools for automated and manual accessibility testing are also summarized.

1. Web Accessibility & WCAG 2.0
Srinivasu Chakravarthula
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YAHOO! CONFIDENTIAL

2. Areas that internet is used
 Education
 Work
 Research
 Entertainment
 Shopping
 Find a place
 Social networking
 Marketing
 Communication

3. Statistics – Internet users world wide –
28.7%
Source: http://www.internetworldstats.com/stats.htm
WORLD INTERNET USAGE AND POPULATION STATISTICS
Population Internet Users Internet Users Penetration Growth Users %
World Regions
( 2010 Est.) Dec. 31, 2000 Latest Data (% Population) 2000-2010 of Table
Africa 1,013,779,050 4,514,400 110,931,700 10.9 % 2,357.3 % 5.6 %
Asia Source:
3,834,792,852 114,304,000 825,094,396 21.5 % 621.8 % 42.0 %
Europe http://www.internetworldstats.com/stats.ht
813,319,511 105,096,093 475,069,448 58.4 % 352.0 % 24.2 %
Middle East
m
212,336,924 3,284,800 63,240,946 29.8 % 1,825.3 % 3.2 %
North America 344,124,450 108,096,800 266,224,500 77.4 % 146.3 % 13.5 %
Latin
592,556,972 18,068,919 204,689,836 34.5 % 1,032.8 % 10.4 %
America/Caribbean
Oceania / Australia 34,700,201 7,620,480 21,263,990 61.3 % 179.0 % 1.1 %
WORLD TOTAL 6,845,609,960 360,985,492 1,966,514,816 28.7 % 444.8 % 100.0 %

4. Asia has 825.1 million Internet users

5. People with disabilities
 Situation
 Functional

6. How do they use computers and
internet?

7. Disability statistics
 Approximately, there are about 78 million people with disabilities
Source: http://codi.buffalo.edu/graph_based/.demographics/.statistics.htm
 There would be reasonably good number of people with disabilities use the Computers
and Internet, because
› There is a rapid development in the area of assistive technology
› There is AT for every disability

8. People with disabilities benefit from
 Offers more independence
Internet
 Need not to worry about inaccessible infrastructure and inaccessible transport
 Get things done right from home

9. What’s the issue?
97% of websites
are inaccessible!
Source: 456BEREAST – Posted in December 2006
http://www.456bereastreet.com/archive/200612/97_of_websites_still_inaccessible/
UN Global Audit of Web Accessibility conducted a survey on Web Accessibility!

10. Accessibility is not just for people with
disabilities but also…
• Low band width users
• Senior citizens
• Search engines
• Mobile users

11. Some of the common misconceptions…
 Accessibility is an additional effort
 Accessibility is just for visually impaired users
 Accessibility is an expensive task
 Need to provide a separate text version of the website

12. Solution…
 Consider accessibility right at the initial stage of the project
 Web Content Accessibility Guidelines (WCAG) 2.0 – http://w3.org/tr/wcag20/
 Accessible Rich Internet Applications (ARIA) - http://www.w3.org/WAI/intro/aria.php
 Authoring Tool Accessibility Guidelines (ATAG) - http://www.w3.org/WAI/intro/atag.php

13. Web Content Accessibility
Guidelines (WCAG) 2.0

14. Definitions
 Principle 1: Perceivable
› Information and user interface components must be presentable to users in ways they can
perceive.
 Principle 2: Operable
› User interface components and navigation must be operable.
 Principle 3: Understandable
› Information and the operation of user interface must be understandable
 Principle 4: Robust
› Content must be robust enough that it can be interpreted reliably by a wide variety of user agents,
including assistive technologies.

15. Guideline 1: Perception
 Non-text content
› Images
› CAPTCHA
› Audio / Video

16. Guideline 1: Perceivable – contd.,
 Sufficient Color Contrast

17. Guideline 2: Operable
 Keyboard access – all information and functionality should be available to access via
keyboard including:
› Links
› Headings
› Form fields
› Lists
› Tables

18. Principle 3: Understandable
 Use of Natural Language – unless a specific terminology is required
 Predictable – User should be able to predict the result upon his action
 Input assistance – provide adequate help for user to interact with forms etc.

19. Principle 4: Robust
 Maximize Compatibility with current and future user agents including assistive
technologies
 Provide name, role and value to all the elements

20. Accessible Rich Internet Applications (ARIA)
 ARIA is WAI Recommendation http://www.w3.org/WAI/intro/aria.php
 WAI-ARIA, the Accessible Rich Internet Applications Suite, defines a way to make
Web content and Web applications more accessible to people with disabilities. It
especially helps with dynamic content and advanced user interface controls
developed with Ajax, HTML, JavaScript, and related technologies.
 Creating Accessible widgets with ARIA http://ericmiraglia.com/blog/?p=132

21. Html 5 and accessibility
 Best resource:
http://html5accessibilit
y.com

22. YUI and Accessibility
 We have a lot of accessible controls in YUI 3 such as TabView, Menu, Calendar and so
on…
 We have used ARIA to make the widgets accessible
 See the blog with videos at http://yuiblog.com/blog/category/accessibility

23. Accessibility Testing
Automated Tools Manual Testing
(Eg: Wave/ FAE) + (Eg: Screen Reader)
=
Accessibility Testing

24. Automated Testing
 WAVE – http://wave.webaim.org/toolbar
 Web Developer Kit - https://addons.mozilla.org/en-US/firefox/addon/60
 Color Contrast Analyzer - http://visionaustralia.org/info.aspx?page=628

25. Accessibility Testing – Manual
 http://twiki.corp.yahoo.com/view/Accessibility/AccessibilityTwiki#qa_corner
› Easy Testing with NVDA
› Reporting Accessibility Issues in Bugzilla and more…
 Screen Readers
› NVDA – http://www.nvda-project.org
› NVDA with necessary settings from Yahoo! Accessibility Team -
http://twiki.corp.yahoo.com/view/Accessibility/AccessibilityTrainingClass#install-instructions

26. Accessibility Testing – Mobile
 iPhone, iPad and iPod touch
› VoiceOver – screen reader that helps users with vision impairment
› Zoom – for low vision users
› Mono Audio – closed captioning and TTY for people who are hard of hearing
› Text prediction – for people who have difficulty in typing
 Symbian OS:
› Provides built in screen reader support
› Need to use third party software like Talks or Mobile Speak for other functionality

27. Questions?

28. Thank you!
Email: srinivu@yahoo-inc.com
Twitter: @VasuTweets
Yahoo! Accessibility Media Outlet:
Blog – http://accessibility.yahoo.com
Facebook: http://facebook.com/yahooaccessibility
Twitter: @yahooaccess