Custom term paper Web accessibility

People who are blind can read the news, people who are deaf can get up-to-the-minute news that earlier were available only for people who can hear (such as TV or radio). People with guadriplegia who cannot move their arms or legs can shop on-line to get groceries, gadgets, and gifts delivered. People who cannot speak can participate in on-line discussions, such as through blog-comments.
Web accessibility focuses on people with all types of disabilities – visual, auditory, physical, speech, cognitive, and neurological disabilities – including older people with age-related impairments. (Thatcher, et al., 2006)
Web accessibility aims to dispose of those problems which prevent people with disabilities from using the Internet.
1. Visual
2. Motor/Mobility
3. Auditory: people who are hard of hearing
4. Seizures: Photoepileptic seizures caused by visual strobe or flashing effects.
5. Cognitive/Intellectual: Developmental disabilities, learning disabilities (dyslexia, dyscalculia, etc.), and cognitive disabilities of various origins, affecting memory, attention, developmental “maturity,” problem-solving and logic skills, etc.; (Wikipedia, 2009)
Principles of Accessibility
The problem of web accessibility for people with disabilities is not new. The first rule set of the World Web Consortium (W3C, w3.org) – WCAG 1.0 – was created in 1999. Currently, intensive work on a second version of the standard is in hammering – WCAG 2.0. These standards include a set of rules, following which it is possible to optimize the structure and contents of the site for people with disabilities. For example, all graphics are initially available for the blind, so they should have an explanatory text. There are some examples:
Checkpoint 1.1 Provide a text equivalent for every non-text elements.
Checkpoint 2.2 Ensure foreground and background colour combinations provide sufficient colour contrast etc.
Checkpoint 6.3 Ensure that pages are usable when scripts are turned off, and if this is not possible provide an alternative.
Checkpoint 7.3 Until user agents allow users to freeze moving content, avoid movement in pages.
Checkpoint 10.1 Until user agents allow users to turn off spawned windows, do not cause pop ups without informing the user.
Checkpoint 12.3 Divide large blocks of information onto more manageable groups where natural and appropriate.
Checkpoint 13.1 Clearly identify the target of each link.
Checkpoint 14.1 Use the clearest and simplest language appropriate for the site content.
The primary goal of these guidelines is to promote accessibility. However, following them will also make Web content more available to all users, whatever user agent they are using (e.g., desktop browser, voice browser, mobile phone, automobile-based personal computer, etc.) or constraints they may be operating under (e.g., noisy surroundings, under- or over-illuminated rooms, in a hands-free environment, etc.). (DRC, 2004)
In spite of some people cannot use video files, images, sounds, or applets, they can use pages, which include so called equivalent information. Equivalent information should have the same informational content as the original page. In some cases the equivalent can only describe the appearance of the visual content or sounds of the auditory content. It is very important to develop exactly text-equivalents of non-text content (images, pre-recorded audio, and video). The power of text equivalents lies in their capacity to be rendered in ways that are accessible to people from various disability groups using a variety of technologies (W3C Note, 2000). Text can be output to speech synthesizers and Braille displays or can be showed on the display or the paper. Synthesized speech is important for those people is important for those people, who have some difficulties in reading, that often accompany cognitive disabilities, learning disabilities, and deafness. Braille is more appropriate for people who are both blind and deaf or just for the blind people. Text, displayed visually, is available only for the deaf and the majority of health people.
Text equivalents for multimedia
Provide a text equivalent for every non-text element (e.g., via “alt”, “longdesc”, or in element content). This includes: images, graphical representations of text (including symbols), image map regions, animations (e.g., animated GIFs), applets and programmatic objects, ascii art, frames, scripts, images used as list bullets, spacers, graphical buttons, sounds (played with or without user interaction), stand-alone audio files, audio tracks of video, and video. When it is necessary text equivalentshould be provided with visual information to make the page more understandable.custom term paper
For example, in HTML:
• Use “alt” for the IMG, INPUT, and APPLET elements, or provide a text equivalent in the content of the OBJECT and APPLET elements.
• For complex content (e.g., a chart) where the “alt” text does not provide a complete text equivalent, provide an additional description using, for example, “longdesc” with IMG or FRAME, a link inside an OBJECT element, or a description link.
• For image maps, either use the “alt” attribute with AREA, or use the MAP element with A elements (and other text) as content. (W3C Note, 2000)
If OBJECT is used, provide a text equivalent in the content of the element:
Example.
<OBJECT classid=”java:Press.class” width=”500″ height=”500″>
As temperature increases, the molecules in the balloon…
</OBJECT>
End example.
A more complex example takes advantage of the fact the OBJECT elements may be embedded to provide for alternative representations of information (W3C Note, 2000):
Example.
<OBJECT classid=”java:Press.class” width=”500″ height=”500″>
<OBJECT data=”Pressure.mpeg” type=”video/mpeg”>
<OBJECT data=”Pressure.gif” type=”image/gif”>
As temperature increases, the molecules in the balloon…
</OBJECT>
</OBJECT>
</OBJECT>
If web-designer wants his site to be accessible he should not rely only on colour and make the content of his site available for people, who do not differentiate between certain colors. Checkpoint 7.3 according to the animated images says that until user agents allow users to freeze moving content, avoid movement in pages.
Embedding multimedia objects
Other objects, such as those requiring a plug-in, should also use the OBJECT element. However, for backward compatibility with Netscape browsers, use the proprietary EMBED element within the OBJECT element as follows:
Deprecated example.
<OBJECT classid=”clsid:A12BCD3F-GH4I-56JK-xyz”
codebase=”http://example.com/content.cab” width=100 height=80>
<PARAM name=”Movie” value=”moviename.swf”>
<EMBED src=”moviename.swf” width=100 height=80
pluginspage=”http://example.com/shockwave/download/”>
</EMBED>

<NOEMBED>
<IMG alt=”Still from Movie”
src=”moviename.gif” width=100 height=80>
</NOEMBED>

</OBJECT>
(W3C Note, 2000)
As an example for the evaluation we can take one of the most famous and wide-spread on-line encyclopedia www.britannica.com. This web-site corresponds to the checkpoint 1.1 and 2.2: almost every non-text element is provided by its text equivalent, animation on the web site is accompanied by the text explanation, but on the other hand these explanations change too fast, so the people with poor sight can have problems with understanding of the content. Foreground and background colour combinations provide appropriate contrast with its blue-orange colour design. White-coloured letters on the buttons also provide the sufficient colour contrast.
Video-files are accompanied by the voice commentaries, but there is neither sign language translation nor text explanation (subtitles) to make this content understandable for the deaf or hard hearing people. Using for example browser Mozilla Firefox, the user can change the scale of the picture, but can’t choose only text. It is possible to access almost all areas of the website without the use of a mouse, but it is not convenient, because the location of the pointer can be seen only in address line below, that will be great inconvenience for people with sight problems. There is a site map, but it is too inconvenient, the person should search a lot to find the necessary information, besides the most part of the menu is written using very small script. Link text completely makes sense out of context and reflects its content.
According to the WAVE report (on-line web accessibility evaluation tool) site www.britannica.com containes 62 accessibility errors. Thus, on the one hand, Britannica.com is one of the widely used web-sites, but it does not correspond to all necessary requirements, which provide the comfortable use of the Internet by people with disabilities.
Millions of people with disabilities are unable to use the Internet, so the aim of web accessibility and modern web designers to remove all barriers, which can affect these people to use the Web completely. Using the Web people with disabilities really can make their life better: they can communicate, know something new about their health problems and ways to solve them, they can earn money without leaving their houses, and they can live without feeling of loneliness and despair.
Besides, as it was already mentioned above, web accessibility benefits a lot people without disabilities, because, a key principle of Web accessibility is designing Web sites and software that are flexible to meet different user needs, preferences, and situations (Web Accessibility Initiative, 2010). For example when person has very slow connection or bad software or has so called “temporary disabilities” such as broken leg or temporary problems with sight.