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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.
Common Web Accessibility Challenges and Solutions
Blindness
Challenges |
Solutions |
Images,
photos, graphics are unusable. |
Provide text
descriptions, in "alt" tags and, if necessary, longer explanations
(either on the same page or with a link to another page). |
Users often
listen to the Web pages using a screen reader. |
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. |
Users often jump from
link to link using the TAB key. |
Make sure that links make sense
out of context ("click here" is problematic). |
Users generally do
not use a mouse. |
Don't write scripts that require
mouse usage. Supply keyboard alternatives. |
Not all screen
readers support image maps. |
Supply redundant text links for hot
spots in image maps. |
It may be difficult
for users to tell where they are when listening to table cell contents |
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. |
Complex tables
and graphs that are usually interpreted visually are unusable. |
Provide summaries and/or
text descriptions. |
Frames
cannot be "seen" all at once. They must be visited separately,
which can lead to disorientation. |
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"). |
| Colors are unusable. |
Do not rely on color
alone to convey meaning. |
Users expect
links to take them somewhere. |
Don't write scripts in
links that don't have true destinations associated with them (e.g. href="javascript:
function(this)"). |
Color Blindness
| Challenges |
Solutions |
Reds and greens are
often indistinguishable. |
Avoid juxtaposing these colors. |
Other
colors may be indistinguishable. |
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. |
Weak Vision
| Challenges |
Solutions |
Users often use screen
enlargers. |
To reduce that amount of horizontal
scrolling, use relative rather than absolute units (e.g. use percentages
for table widths instead of pixels). |
Text in graphics does
not enlarge without special software, and looks pixelated when enlarged. |
Limit or eliminate text within
graphics. |
Deafness (Hearing)
| Challenges |
Solutions |
Audio is unusable. |
Provide transcripts for audio
clips.
Provide synchronous captioning for video clips. |
Motor Impairments
| Challenges |
Solutions |
Users may not be able
to use the mouse. |
Make sure that all functions are
available from the keyboard (try tabbing from link to link). |
Users may become fatigued
when using "puff-and-sip" or similar adaptive technologies. |
Provide a method for skipping over long
lists of links or other lengthy content. |
Users may be using voice
activated software. |
Voice-activated software generally cannot
replicate mouse movement, so make sure that all functions are available
from the keyboard. |
Users may not be able to
control the mouse or the keyboard well. |
Voice-activated software generally cannot
replicate mouse movement, so make sure that all functions are available
from the keyboard. |
Users may not be able to
control the mouse or the keyboard well. |
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. |
Cognitive Impairments
| Challenges |
Solutions |
Users may become confused
at complex layouts or inconsistent navigational schemes. |
Simplify the layout as much as
possible.
Keep the navigational schemes as consistent as possible. |
Users may have difficulty
focusing on or comprehending lengthy sections of text. |
Where appropriate, group textual
information under logical headings. Organize information in manageable "chunks." |
One method of input
may not be sufficient. |
Where appropriate, supplement
text with illustrations or other media, and vice versa. |
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