Transcript The Internet Writer`s Handbook 2/e

Web Accessibility
Writing for the Web
The Internet Writer’s Handbook 2/e
Contents
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Accessibility background
Accessibility guidelines
References
The Internet Writer’s Handbook 2/e
Accessibility: Background
The Internet Writer’s Handbook 2/e
Intended Audience of
Accessibility Initiatives
Users unable to:
 See, hear, move.
 Process some types of information.
 Read or understand text or language.
 Use a keyboard or mouse.
 Use a large screen.
 Have fast Internet connection.
 Have new browser.
The Internet Writer’s Handbook 2/e
Web Accessibility Initiative of
the World Wide Web Consortium
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Developed accessibility guidelines.
The Internet Writer’s Handbook 2/e
W3C WAI Standards
1. Provide equivalent alternatives to
auditory and visual content.
2. Don't rely on color alone.
3. Use markup and style sheets properly.
4. Clarify natural language usage.
The Internet Writer’s Handbook 2/e
W3C WAI Standards
5. Create tables that transform gracefully.
6. Ensure that pages featuring newer
technologies transform gracefully.
7. Ensure user control of time-sensitive content
changes.
8. Ensure direct accessibility of embedded user
interfaces.
9. Design for device-independence.
10. Use interim solutions.
The Internet Writer’s Handbook 2/e
W3C WAI Standards
11. Use W3C technologies and guidelines.
12. Provide context and orientation
information.
13. Provide clear navigation mechanisms.
14. Ensure that documents are clear and
simple.
The Internet Writer’s Handbook 2/e
W3C WAI Priority 1
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A Web content developer must satisfy
this checkpoint. Otherwise, one or more
groups will find it impossible to access
information in the document.
Satisfying this checkpoint is a basic
requirement for some groups to be able
to use Web documents.
The Internet Writer’s Handbook 2/e
W3C WAI Priority 2
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A Web content developer should satisfy
this checkpoint. Otherwise, one or more
groups will find it difficult to access
information in the document.
Satisfying this checkpoint will remove
significant barriers to accessing Web
documents.
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W3C WAI Priority 3
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A Web content developer may address
this checkpoint. Otherwise, one or more
groups will find it somewhat difficult to
access information in the document.
Satisfying this checkpoint will improve
access to Web documents.
The Internet Writer’s Handbook 2/e
Accessibility Guidelines
The Internet Writer’s Handbook 2/e
1. Provide equivalent alternatives to
auditory and visual content
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Images
Graphical representations of text (including
symbols)
Image map regions
Animations (e.G., Animated gifs)
Applets and programmatic objects
ASCII art
Frames
Scripts
The Internet Writer’s Handbook 2/e
1. Provide equivalent alternatives to
auditory and visual content
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Images used as list bullets
Spacers
Graphical buttons
Sounds (played with or without user
Interaction)
Stand-alone audio files
Audio tracks of video
Video
The Internet Writer’s Handbook 2/e
1. Provide equivalent alternatives to
auditory and visual content
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Provide redundant text links for each active
region of a server-side image map.
Provide an auditory description of the
important information of the visual track of a
multimedia presentation.
For any time-based multimedia presentation,
synchronize equivalent alternatives (e.g.,
captions or auditory descriptions of the visual
track) with the presentation.
The Internet Writer’s Handbook 2/e
2. Don't rely on color alone
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Ensure that all information conveyed
with color is also available without color
(e.g., from context or markup).
The Internet Writer’s Handbook 2/e
3. Use markup and style sheets
properly
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Not priority 1
The Internet Writer’s Handbook 2/e
4. Clarify natural language
usage
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Clearly identify changes in the natural
language of a document's text and any
text equivalents (e.g., captions).
The Internet Writer’s Handbook 2/e
5. Create tables that transform
gracefully
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For data tables, identify row and column
headers.
For data tables that have two or more
logical levels of row or column headers,
use markup to associate data cells and
header cells.
The Internet Writer’s Handbook 2/e
6. Ensure that pages featuring new
technologies transform gracefully
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Organize documents so they may be
read without style sheets.
Ensure that equivalents for dynamic
content are updated when the dynamic
content changes.
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6. Ensure that pages featuring new
technologies transform gracefully
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Ensure that pages are usable when
scripts, applets, or other programmatic
objects are turned off or not supported.
If this is not possible, provide equivalent
information on an alternative accessible
page.
The Internet Writer’s Handbook 2/e
7. Ensure user control of timesensitive content changes
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Until user agents allow users to control
flickering, avoid causing the screen to
flicker.
The Internet Writer’s Handbook 2/e
8. Ensure direct accessibility of
embedded user interfaces
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Make programmatic elements such as
scripts and applets directly accessible or
compatible with assistive technologies.
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9. Design for deviceindependence
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Provide client-side image maps instead
of server-side image maps except where
the regions cannot be defined with an
available geometric shape.
The Internet Writer’s Handbook 2/e
10. Use interim solutions
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Not Priority 1
The Internet Writer’s Handbook 2/e
11. Use W3C technologies and
guidelines
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Not Priority 1
The Internet Writer’s Handbook 2/e
12. Provide context and
orientation information
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Title each frame to facilitate frame
identification and navigation.
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13. Provide clear navigation
mechanisms
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Not Priority 1
The Internet Writer’s Handbook 2/e
14. Ensure that documents are
clear and simple
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Use the clearest and simplest language
appropriate for a site's content.
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Tools for Evaluating
Accessibility
The Internet Writer’s Handbook 2/e
Bobby
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Web-based public service offered by the
Center for Applied Special Technology
(CAST).
Analyzes Web pages for their
accessibility to people with disabilities
and compatibility with various browsers.
http://www.www.cast.org/bobby/
The Internet Writer’s Handbook 2/e
The Wave
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Tool to help determine your page's
accessibility by presenting the
"linearized" reading order, ALT text for
images and image map areas, and the
applet alternatives.
http://www.temple.edu/
inst_disabilities/piat/wave/
The Internet Writer’s Handbook 2/e
TOM, the Text-Only Maker
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Developed at developed at the National
Center for Supercomputing Applications
(NCSA).
Converts graphical Web pages into textonly pages or text and graphics Web
pages.
http://www..eot.org/TTF/Access/tom.html
The Internet Writer’s Handbook 2/e
W3C
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Checks HTML documents for
conformance to W3C HTML and XHTML
recommendations and other HTML
standards.
http://validator.w3.org/
The Internet Writer’s Handbook 2/e
References
The Internet Writer’s Handbook 2/e
References
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W3C WAI www.w3c.org/wai
Access Adobe access.adobe.com
IBM Accessibility Center www3.ibm.com/able/overview.html
Microsoft Accessibility
www.microsoft.com/enable
The Internet Writer’s Handbook 2/e
References
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Center for Applied Special Technology
(CAST) www.cast.org
Do-IT www.washington.edu/doit
WebABLE www.webable.com
The Internet Writer’s Handbook 2/e
The Internet Writer’s Handbook 2/e