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:

Guideline 5. Create tables that transform gracefully.

Ensure that tables have necessary markup to be transformed by accessible browsers and other user agents. Tables should be used to mark up truly tabular information (“data tables”). Content developers should avoid using them to lay out pages (“layout tables”). Tables for any use also present special problems to users of screen readers (refer to checkpoint 10.3).

Guideline 4. Clarify natural language usage.

Use markup that facilitates pronunciation or interpretation of abbreviated or foreign text. When content developers mark up natural language changes in a document, speech synthesizers and braille devices can automatically switch to the new language, making the document more accessible to multilingual users. Content developers should identify the predominant natural language of a document’s content (through markup or HTTP headers). Content developers should also provide expansions of abbreviations and acronyms.

Guideline 3. Use markup and style sheets and do so properly.

Mark up documents with the proper structural elements. Control presentation with style sheets rather than with presentation elements and attributes.

2. Don’t rely on color alone.

Ensure that text and graphics are understandable when viewed without color. If color alone is used to convey information, people who cannot differentiate between certain colors and users with devices that have non-color or non-visual displays will not receive the information. When foreground and background colors are too close to the same hue, they may not provide sufficient contrast when viewed using monochrome displays or by people with different types of color deficits. Checkpoints:

Guideline 1. Provide equivalent alternatives to auditory and visual content.

Provide content that, when presented to the user, conveys essentially the same function or purpose as auditory or visual content.

5. Conformance to the W3C recommended guidelines.

This section defines three levels of conformance to this document: * Conformance Level “A”: all Priority 1 checkpoints are satisfied; * Conformance Level “Double-A”: all Priority 1 and 2 checkpoints are satisfied; * Conformance Level “Triple-A”: all Priority 1, 2, and 3 checkpoints are satisfied; Note. Conformance levels are spelled out in text so they may be understood when rendered to speech. Claims of conformance to the full set of Guidelines must use one of the following two forms. Form 1: Specify:

4. Priorities

Each checkpoint has a priority level assigned by the Working Group based on the checkpoint’s impact on accessibility. [Priority 1] A Web content developer must satisfy this checkpoint. Otherwise, one or more groups will find it impossible to access information in the document. Satisfying this checkpoint is a basic requirement for some groups to be able to use Web documents. [Priority 2]

3. How the Guidelines are Organized

This document includes fourteen guidelines, or general principles of accessible design. Each guideline includes: * The guideline number. * The statement of the guideline. * Guideline navigation links. Three links allow navigation to the next guideline (right arrow icon), the previous guideline (left arrow icon), or the current guideline’s position in the table of contents (up arrow icon). * The rationale behind the guideline and some groups of users who benefit from it. * A list of checkpoint definitions.

2. Themes of Accessible Design

The guidelines address two general themes: ensuring graceful transformation, and making content understandable and navigable. 2.1 Ensuring Graceful Transformation By following these guidelines, content developers can create pages that transform gracefully. Pages that transform gracefully remain accessible despite any of the constraints described in the introduction, including physical, sensory, and cognitive disabilities, work constraints, and technological barriers. Here are some keys to designing pages that transform gracefully: