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Technological and Evaluation Foundations of Accessible
WebOssi Nykänen
Tampere University of Technology, Department of Mathematics, W3C Finnish Office.
A presentation for Media Goes Accessible 19.1.2012, at Aalto University
2/28
Introduction
● Abstract● Web technologies and accessibility guidelines are
developed at the W3C. In this presentation we outline both, and consider how certain legacy problems of the ”desktop Web” could be overcome
● Outline of the presentation● World Wide Web Consortium (W3C) and Web
Technologies● Web Accessibility Initiative (WAI)● Beyond Legacy Assumptions
Part I:
W3C and Web Technologies
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World Wide Web Consortium (W3C)
● Founded in 1994 with the vision of “One Web,” open to all
● Today Web is everywhere
● Web was invented by Sir Tim Berners-Lee, the W3C Director
5/28
W3C (Cont'd)
● W3C is an international consortium where Member organizations, a full-time staff, and the public work together to develop Web standards ● Director Tim Berners-Lee, CEO Jeff
Jaffe● Standards and guidelines for
the long-term growth for the Web (cf. HTML, XML, WAI, Mobile Web)
● Over 300 members – welcome (myösW3C Suomen toimisto)
6/28
W3C value proposition
Key properties● International organization● Strong Web community● Track record of success● Neutral forum for collaboration
across industries, ecosystems and communities
● Broad industry and academic participation (e.g. Browser, mobile, internet and corporate)
● Active, expert staff participating in work
Broad reach● Translations of standards to 55+
languages● Liaisons w/ 40+ global standards
organizations (UN, ISO, ITU, IETF, OGF, Unicode, ICANN, ETSI, Isoc…)
● 55,000+ people subscribed to 800+ mailing lists
● Millions of Hits/day on www.w3.org● 220+ Web standards:(HTML, XML,
PNG/SVG,RDF/OWL/SPARQL, Accessibility….)
● 1,800+ participants in 60+ Groups
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…The W3C Open Web Platform
8/28
W3C One Web: Principles and vision
● Web for All ● Web Accessibility
Initiative; Internationalization; Mobile Web for Social Development
● Web on Everything● Web of Devices; Mobile
Web Initiative; Browsers and Other Agents
● Web for Rich Interaction● Web Design and
Applications; Web Architecture
● Web of Data and Services● Essential XML
Technologies; Semantic Web; Web of Services
● Web of Trust● Semantic Web; XML
Security, Web of Services Security; Privacy
9/28
W3C Web technology stack
10/28
Current work (lots of)
● Group structure, patent policy● Advisory, architecture, working,
incubator, interest, community, business, ...
● Events and workshops● Hot topics
● Television, HTML5, Data and Service Integration, ..
11/28
What about Web and accessibility?
● Accessibility requires several things, e.g.● Understanding, willingness, and know-how for
supporting true user needs● Supportive tools and feedback● Enabling technology incl. open interfaces
● Thus, (Web) accessibility needs to be build into the technologies (and specified in that context)● Also needed: Active community, best practices,
technical guidelines, continuous evaluation, ...
Part II:
Web Accessibility Initiative
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Web Accessibility Initiative
● The W3C Web Accessibility Initiative (WAI) develops strategies, guidelines, and resources to help make the Web accessible to people with disabilities (or context-specific challenges)
● Launched in 1997, directed by Judy Brewer● Accessibility built-in for Web
technologies● Guidelines and training materials● Outreach, projects, ...● Basis for many regulations
14/28
Web Content Accessibility
● Accessibility is a property of a ”Web page” (incl. apps) that enables successfully using it
● Improve accessibility via four key principles:● Perceivable● Operable● Understandable● Robust
● ...while paying attention to accessibility issues, perhaps when using assistive technologies
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Interaction of roles and tools is needed
● Visit Essential Components of Web Accessibility
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Pivotal guidelines and techniques
● Standards and documented techniques● Web Content (WCAG) (also WCAG 2.0 in Finnish) ● Authoring Tool (ATAG); v2.0 in progress● User Agent (UAAG); v2.0 in progress● Evaluation Language (EARL); work in progress● Rich Applications (WAI-ARIA); work in progress
● Also resources for● Planning, implementing, managing,
evaluating, getting involved with WAI, etc.
17/28
Evaluating and reporting accessibility
● Two basic ways of testing:● Preliminary review● Conformance evaluation
● Reporting is important● ”Who, what, criterion,
results”● In the future, reporting
can be done in machine-readable exchange format, using the Evaluation and Report Language (EARL) 1.0...
18/28
Tips for hands-on work
● Visit Getting Started with Web Accessibility● Try out the Before and After Demonstration● Design your applications with users and test● Visit also the W3C Mobile Web Initiative
19/28
Notes
● Accessibility is a commonplace design requirement that is also present during the application evolution phase (cf. security)
● Technologies should be used in ways that are ”accessibility supported” (cf. device independence)
● Content should be ”programmatically determined” (cf. Machine-understandable)● ...adding descriptions à la Semantic Web
20/28
Notes (cont'd)
● Application functionality should be available via a keyboard interface
● Accessibility features of applications should be documented
● There should be an easy way for users to provide (contextual) feedback
● Hm. Why do we fall into these pitholes?
Part III:
Beyond Legacy Assumptions
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Thinking outside the box
● Obviously, the W3C WAI and practitioners need to deal with the current issues, where many applications emphasise visual design
● But things are in motion, consider...● What does using an application ”mean”?● Enriching current applications (WAI-ARIA)● Enriching evaluation feedback (EARL)
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What does using an application ”mean”? (Read: We currently spend lot of efforts to describe the graphical user interface...)
● According to a desktop metaphor (”a legacy example”):● Read instructions, navigate to appropriate view, fill in a visual form
fields, click button to submit, read scripted response (loop)● Not a disaster if Perceivable, Oper..., Und..., and Ro..., but really:
● From a functional user experience point of view:● Search information, iterate down to matching functionality, provide
task parameters and execute, query results (loop)● Logically, applications provide information and functions –
”buttons” etc. are part of the user interface implementation● Tough challenges ahead: Getting overview; naming and matching
tasks and functionality; certain kinds of input; remembering state and history; accessing specific sensory experiences
24/28
Enriching current applications (WAI-ARIA)
● The basic approach for programmatically determining things is to write ”semantics” out (with commonly known model & names)
● A (bad) example of assuming common-sense reasoning:● User interface: Piece of HTML code (e.g. ”<div>”) is a button if it
happens to behave like one (and looks like it)● From machine-understandable semantic point of view:
● Instead of ”<div>”, say ”<div role='http://www.w3.org/ns/wai-aria/button'>” (i.e. using the standard ARIA taxonomy)
● Even better, anticipate to say ”<button>” in HTML5...● Result: The Controls of the user interface can be identified● Perhaps something similar could be applied to functions?
25/28
Enriching evaluation feedback (EARL)
● Integrating and processing narrative eval feedback is tedious – luckily, this can be modelled similarly as well
● A example of assuming common-sense reasoning:● Report: A report says that the page ”www.example.org” fails to
provide alt attributes for images (and hence is not WCAG 2.0-A)● Considering machine-understandable semantics, say also:
...<earl:Assertion rdf:about="#assertion">
<earl:subject rdf:resource="http://www.example.org/"/> <earl:test rdf:resource="http://www.w3.org/TR/WCAG20-TECHS/H36"/> <earl:result rdf:resource="#result"/>
</earl:Assertion>
<earl:TestResult rdf:about="#result"> <earl:outcome rdf:resource="http://www.w3.org/ns/earl#failed"/> </earl:TestResult>...
● Result: tests can be integrated and automatically processed
26/28
Fundamental challenges (?)
● Old legacy content and apps● New applications – and dev tools – are (still)
often developed visual design in mind● Locking applications ”just in case” for business
reasons etc. (vs. Open interfaces & linked data)● New apps, technologies, and devices
sometimes re-invent the old (solved?) mistakes● Everything isn't rocket science, but training is
needed; accessibility is also a moving target
Part IV:
The Final Words
28/28
Conclusion
● W3C develops Web for all● Mindful development, testing, and evaluation are the
cornerstones of accessible Web design● The future of accessibility lies in machine-
understandability of information and tasks (?)● With proper mindset and tools, many accessibility
challenges can be solved● Thank you!
● Something still in mind? (Contact: Ossi Nykänen, [email protected], [email protected])