Accessibility
Considering the diversity of users who are likely to visit your site is vital in creating a successful and popular web resource.
Making sure that a website is not only informative and engaging, but also user-friendly to visitors who may be using different browsers, alternative input devices or assistive technologies is a crucial step in planning and developing any site.
Considerations might include:
Browser compatibility
- Internet Explorer, Mozilla, Opera, etc.Language used
- HTML 4.01 Transitional, XHTML, PHP, ASP, etc.'HTML 4 supports more multimedia options, scripting languages, style sheets, better printing facilities, and documents that are more accessible to users with disabilities.' ( http://www.w3.org/TR/html4)
Styles
- The use of cascading style sheets (CSS) is imperative to make web resources accessible. Using remotely governed styles allows users to overwrite preferences set within the style sheet to reflect their own needs, such as background colour, text size, font, etc.Layout
- Use of correctly labelled tables or layers to control layout of elements on a page. Descriptive text and annotation is important to assist screen readers make sense of the textual or media content.Metadata
- Descriptive content in a page that allows sites to be categorised according to subject.Text size
- This should be governed by CSS and be relative rather than absolute. 'x-small', 'small', etc are recommended by the W3C but some developers prefer text to be % based. (http://www.w3.org/TR/2004/WD-WCAG20-CSS-TECHS-20040730/#fonts)Links
- Explanatory links help screen readers make sense of content and help to differentiate from the rest of a page. Ambiguous 'click here' links are not very helpful.Tab order
- Allows users to navigate through the main components of a page using a keyboard.Access keys
- Specially allocated keys that allow alternative access content, other than using a mouse.Use of Javascript
- Useful in extending functionality, but can cause problems with screen readers.Skip navigation
- Simple link that allows users to bypass navigation every time a new page is loaded, lessen this repetitive content and go straight to main content.Alt text and D link
- All images, whether basic or complex, should be accompanied by descriptive alternative text, again for use by screen readers. A D-link allows further explanation of Alt text, should an image warrant it.Text only
- Can be a useful alternative if users wish only text content. Is a point of contention amongst many developers in terms of compromise in parity of user experience.User testing
- The best way to check if a site is usable and accessible. Testing ease of use of interface and navigation with a variety of users with diverse preferences and browsing habits is a rigorous way to maximise the potential of your site.Further info:
http://www.w3.org/TR/WAI-WEBCONTENT-TECHS/http://www.alistapart.com/topics/accessibility/
http://validator.w3.org/
http://jigsaw.w3.org/css-validator/
http://wave.webaim.org/index.jsp
http://www.usablenet.com/
© Virtual V 2006