Search Engine Optimization

This purpose of this page is to outline principles for helping web designers create accessible web content which is beneficial to Search Engine Optimization .

If these principles are ignored, individuals with disabilities may not be able to access your content. When these principles are employed, they make web content accessible to a variety of web-enabled devices such as phones, handheld devices, kiosks, and other network appliances.

Those who benefit from standards-compliant pages

• People who cannot hear will want a visual representation of information presented via sound
• People who cannot see will want to hear or feel [ via Braille or tactile graphics ] an equivalent of the visual information
• People who do not have the strength to move quickly or easily will want to use as little movement as possible and have as much time as they need when operating web interfaces
• People who do not read well may want to hear the information read aloud

Accessible web content benefits a variety of people, not just people with disabilities. In the physical world, ramps are used by bicycles, people pushing strollers, and people in wheelchairs. Similarly, accessible web content is beneficial to a variety of people with and without disabilities. Likewise, it is easier for search engines to locate a famous quote in a movie if the movie has been captioned.

Content must be perceivable

• For non-text content, provide text equivalents that serve the same purpose or convey the same information as the non-text content, except when the sole purpose of the non-text content is to create a specific sensory experience in which case a text label or description is sufficient
• Provide synchronized media equivalents for time-dependent presentations. An audio description of visual events is provided for audio-visual media. Captions are provided for all significant dialogue and sounds in time-dependent material. Descriptions and captions are synchronized with the events they represent
• Ensure that information, functionality, and structure are separable from presentation. The following can be derived programmatically from the content without requiring user interpretation of presentation

Hierarchical elements and relationships

• Headings
• Lists
• Paragraphs
• Non-hierarchical relationships between elements
• In visual presentations, make it easy to distinguish foreground words and images from the background. Any text that is presented over a background is electronically available so that it could be re-presented in a form that allows the text to be distinguished from the background
• In audio presentations, make it easy to distinguish foreground speech and sounds from background sounds. Audio content does not contain background sounds or the background sounds are at least 20 decibels lower than the foreground audio content with the exception of occasional short sounds

Interface elements in the content must be operable

• Make all functionality operable via a keyboard or a keyboard interface
• Allow users to control time limits on their reading or interaction unless specific real-time events or rules of competition make such control impossible
• Allow users to avoid content that could cause photosensitive epileptic seizures
• Facilitate the ability of users to orient themselves and move within the content
• Help users avoid mistakes and make it easy to correct them

In general, organize material in an easy fashion. Avoid professional jargon, slang, and other terms with a specialized meaning that may not be clear to people outside a specific group when resources are intended for a general audience or for translation into other languages. Use the simplest sentence forms consistent with the purpose of the content.

Use page design principles, graphics, color, fonts, animations, video, and/or audio to clarify complex text.

All users, especially those with cognitive, learning, and/or reading disabilities benefit from the use of clear and simple writing. This should not discourage you from expressing complex or technical ideas.

Using clear and simple language also benefits people whose first language differs from your own, including those people who communicate primarily in sign language.

Sounds, graphics, videos and animations can help make concepts presented in a website easier to understand, especially for people with cognitive, reading, or learning disabilities or those who are unfamiliar with the language of the text of the site.

Summarizing information that is difficult to understand helps people who do not read well.

Content must be robust enough to work with current and future technologies.

• Use technologies according to specification
• Ensure that user interfaces are accessible or provide accessible alternatives
• Ensure that requirements may be applied across technologies
• Ensure that the conformance requirements are clear
• Ensure that the deliverables are easy to use
• Write to a more diverse audience

By making your content accessible to a variety of devices, your content will be accessible to those in a variety of situations.

These design principles represent broad concepts that apply to all web content. They are not specific to HTML, XML, or any other technology. According to W3 this approach has been taken so that the principles could be applied to a variety of situations and technologies, including those that do not yet exist.

These guidelines have been written to meet the needs of many different audiences from policy makers, managers, web designers, and those who write code.

If your web content employs these design principles, then users should be able to access the content using adaptive strategies and assistive technologies. There are many tools that people with disabilities employ to make use of web content. For more in-depth scenarios of people with disabilities using accessible and inaccessible web content, read " How People with Disabilities Use the Web ".