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Designing for Accessibility By Joel Sklar Any large audience for a Web site will include users who have physical challenges to accessing your content. Designing for accessibility means that you should be developing Web pages that will remain accessible despite any physical, sensory, and cognitive disabilities, work constraints, or technological barriers. Most mainstream Web sites are so heavily image- and media-intensive that they are not suitable for adaptive devices such as screen readers, voice browsers, and braille translators. Many of the guidelines necessary for developing accessible content naturally lend themselves to creating good design.
Images Always use both the ALT and TITLE attributes to describe the each image. You should already be using ALT, but you may not be aware of TITLE. It's a core attribute that you can use within any HTML element. TITLE provides a pop-up description of the element like ALT does. You may be surprised to find that many of the newer browsers display pop-ups only for TITLE and not for ALT, whose purpose is to provide alternate text descriptions of images only if the image does not display. Additionally, TITLE can be used with the <A> element to provide a pop-up description of the link destination. Try it—you'll love the results! Multimedia
and animations Is your multimedia really necessary? Is your company logo spinning distractingly on the main page of your site? Find real uses for your multimedia content and always provide optional paths so that users can choose whether to access it. If you are serious about providing accessible multimedia content, you will have to provide captions and transcripts. Hypertext
links Good writing works for everyone, so use text that makes sense for your hypertext links. Never use “click here” as your link text—it is very poor style, and provides no context or description of the hypertext destination. Always provide text-based linking alternatives on every page. Page organisation and information design Use headings, lists, and consistent structure to enforce the information design of your content. This lets your users easily understand the organisation of your Web site. Provide text-based "breadcrumb trails" on every page to let users locate themselves within your site. Cascading
Style Sheets If you're not using Cascading Style Sheets already, you are missing out on one of the more powerful Web design tools available. The newer browsers offer excellent support for CSS, and you will gain complete control of your sites' design characteristics through a single style sheet file, rather than with hundreds of <font> tags scattered throughout your HTML. To take advantage of CSS's powerful properties you will have to rethink your site's consistency of styles and display characteristics, which ultimately will benefit your users. Frames Most web sites that use frames don't need to, but there are uses for these less-than-well respected design tools. Frames can be great for large collections of content, especially technical documentation. What could be better than having a table of contents always visible to the user in one frame, while the content they want to read displays in another? If you do decide to use frames, make sure to use the <noframes> element to describe your site, and provide an alternative "no frames" path through content. Tables If you are using tables for anything other than tabular data your content is considered less than accessible. This means that very few mainstream Web sites are accessible, because everyone uses tables for page layout. It's hard not to be guilty of this, because every designer wants to break away from the left-justified design of basic HTML. If your users have a newer browser (generally a 6.0 browser or above), you can use the CSS positioning properties (they really do work) but your design will be a mess in the older browsers. The use of tables will continue to be a problem until usage of the newer browsers trickles down to the average user. Validity It's finally time to go back and clean up all that messy code of yours, because the XHTML standard requires HTML code that matches XML syntax rules – meaning your code must be syntactically correct. You can use the built in validator in your HTML editor to check your code to make sure it's up to standard. The more standard everyone's code is, the more accessible it is across different operating systems and media output devices. You can check your Web pages for ease of accessibility to physically-challenged people by using Bobby, a Web-based tool developed by the Center for Applied Special Technology (CAST) at www.cast.org/bobby. Bobby checks your pages by applying the W3C’s Web contents accessibility guidelines to your code and recording the number and type of incompatibility problems it finds. Bobby looks for elements such as consistent use of ALT attributes, appropriate colour usage, compatibility with screen readers, and ease of navigation. You can use Bobby online if your pages are live, or you can download Bobby to test your work on your own machine. Unfortunately, many mainstream Web sites fail Bobby’s requirements for accessibility because they use tables as a page layout device and don't use Cascading Style Sheets. The W3C supports a comprehensive accessibility initiative at www.w3.org/WAI. Here you will find a large variety of guidelines and standards to build more accessible Web content. You can learn more about the adaptive devices for accessible browsing at www.w3.org/WAI/References/Browsing. Remember to keep your Web designs focused solely on your user's information needs, and you'll have taken the first big step in designing for accessibility.
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