Accessible Web Design
Most people today can hardly conceive of life without the Internet. It provides access to information, news, email, shopping, and entertainment. At the click of a mouse, the world can be "at your fingertips"-that is, if you can use a mouse . . . and if you can see the screen . . . and if you can hear the audio-in other words, if you don't have a disability of any kind.
The most universal format for perceivability is text, because it can be transformed into light for the eyes (on a computer screen), sound for the ears (through a screen reader), and Braille for the hands (through a Braille display).
The following resource table below, originally developed by Paul Bohman of WebAIM, will help you in your future endeavors to try to implement principles of accessibility in your work. For a more updated and informative list, go to Designing More Usable Web Sites from the Trace Center at the University of Wisconsin-Madison.
Common Web Accessibility Challenges and Solutions
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Challenges
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Solutions
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Images, photos, graphics are unusable.
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Provide text descriptions, in "alt" tags and, if necessary, longer explanations (either on the same page or with a link to another page).
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Users often listen to the Web pages using a screen reader.
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Allow for users to skip over navigational menus, long lists of items, ASCII art, and other things that might be difficult or tedious to listen to.
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Users often jump from link to link using the TAB key.
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Make sure that links make sense out of context ("click here" is problematic).
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Users generally do not use a mouse.
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Don't write scripts that require mouse usage. Supply keyboard alternatives.
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Not all screen readers support image maps.
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Supply redundant text links for hot spots in image maps. |
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It may be difficult for users to tell where they are when listening to table cell contents
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Provide column and row headers (<th>). Make sure that tables--especially those with merged cells--make sense when read row by row from left to right. |
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Complex tables and graphs that are usually interpreted visually are unusable.
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Provide summaries and/or text descriptions.
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Frames cannot be "seen" all at once. They must be visited separately, which can lead to disorientation.
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Don't use frames unless you have to. If you use them, provide frame titles that communicate their purpose (e.g. "navigational frame", "main content").
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| Colors are unusable. |
Do not rely on color alone to convey meaning.
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Users expect links to take them somewhere.
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Don't write scripts in links that don't have true destinations associated with them (e.g. href="javascript: function(this)").
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| Challenges | Solutions |
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Reds and greens are often indistinguishable.
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Avoid juxtaposing these colors.
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Other colors may be indistinguishable.
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Make sure that there is sufficient contrast, and that the pages would be readable on a black and white monitor. To simulate this, print your Web page to a black and white printer.
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| Challenges | Solutions |
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Users often use screen enlargers.
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To reduce that amount of horizontal scrolling, use relative rather than absolute units (e.g. use percentages for table widths instead of pixels).
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Text in graphics does not enlarge without special software, and looks pixelated when enlarged.
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Limit or eliminate text within graphics.
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| Challenges | Solutions |
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Audio is unusable.
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Provide transcripts for audio clips.
Provide synchronous captioning for video clips. |
| Challenges | Solutions |
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Users may not be able to use the mouse.
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Make sure that all functions are available from the keyboard (try tabbing from link to link).
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Users may become fatigued when using "puff-and-sip" or similar adaptive technologies.
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Provide a method for skipping over long lists of links or other lengthy content.
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Users may be using voice activated software.
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Voice-activated software generally cannot replicate mouse movement, so make sure that all functions are available from the keyboard.
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Users may not be able to control the mouse or the keyboard well.
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Voice-activated software generally cannot replicate mouse movement, so make sure that all functions are available from the keyboard.
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Users may not be able to control the mouse or the keyboard well.
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Make sure that your pages are error-tolerant (e.g. ask "are you sure you want to delete this file?"), do not create small links or moving links.
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| Challenges | Solutions |
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Users may become confused at complex layouts or inconsistent navigational schemes.
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Simplify the layout as much as possible.
Keep the navigational schemes as consistent as possible. |
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Users may have difficulty focusing on or comprehending lengthy sections of text.
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Where appropriate, group textual information under logical headings. Organize information in manageable "chunks."
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One method of input may not be sufficient.
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Where appropriate, supplement text with illustrations or other media, and vice versa.
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