Guideline 6. Ensure that pages featuring new technologies transform gracefully.

Ensure that pages are accessible even when newer technologies are not supported or are turned off.

Although content developers are encouraged to use new technologies that solve problems raised by existing technologies, they should know how to make their pages still work with older browsers and people who choose to turn off features.

Checkpoints:

6.1 Organize documents so they may be read without style sheets. For example, when an HTML document is rendered without associated style sheets, it must still be possible to read the document. [Priority 1] When content is organized logically, it will be rendered in a meaningful order when style sheets are turned off or not supported.

6.2 Ensure that equivalents for dynamic content are updated when the dynamic content changes. [Priority 1]

6.3 Ensure that pages are usable when scripts, applets, or other programmatic objects are turned off or not supported. If this is not possible, provide equivalent information on an alternative accessible page. [Priority 1]

For example, ensure that links that trigger scripts work when scripts are turned off or not supported (e.g., do not use “javascript:” as the link target). If it is not possible to make the page usable without scripts, provide a text equivalent with the NOSCRIPT element, or use a server-side script instead of a client-side script, or provide an alternative accessible page as per checkpoint 11.4. Refer also to guideline 1.

6.4 For scripts and applets, ensure that event handlers are input device-independent. [Priority 2]

Refer to the definition of device independence.

6.5 Ensure that dynamic content is accessible or provide an alternative presentation or page. [Priority 2]

For example, in HTML, use NOFRAMES at the end of each frameset. For some applications, server-side scripts may be more accessible than client-side scripts.