What is accessibility?

W3C director, Tim Berners-Lee, defines web accessibility as "access by everyone, regardless of disability." In website development, accessibility requires that all elements can be accessed by anyone visiting your website.

Disability Categories

There are 5 main disability categories. Understanding these categories will be helpful when developing your content:

1. Cognitive Learning
2. Auditory
3. Visual (including blind, low vision, and color blind)
4. Motor/Physical
5. Speech

Four Principles of Accessibility

The W3C website provides an overview of the Four Principles of Accessibility. These guidelines provide tips and suggestions to follow when creating a website

1) Perceivable

• Provide text alternatives for non-text content using the "alt" tag
• Provide captions, transcripts, and other alternatives for multimedia
• Create content that can be presented in different ways without losing meaning
• Use methods that will make it easier for users to see and hear web content

2) Operable

• Create pages so all functionality is available from a keyboard
• Give users plenty of time to read and use content
• Do not use content that may trigger seizures; avoid producing any content that violates spatial pattern thresholds
• Provide ways for users to find content, navigate, and determine where they are within a website

3) Understandable

• Make text content readable and understandable
• Make content appear and operate in predictable ways
• Help users avoid and correct mistakes; an example would be to hide any optional form fields

4) Robust

• Maximize compatibility with current and future user tools
• Avoid using any technologies that are not accessibility-supported when the technology is turned off or not supported

Quick Tips for Accessibility

These tips provide a brief summary of the Web design concepts that support accessibility standards. For full guidelines and examples, see Web Content Accessibility Guidelines.

• Images and animations: Use the alt attribute to describe the function of each visual.
• Image maps: Use the client-side map and text for hotspots.
• Multimedia: Provide captioning and transcripts for audio, and descriptions of video.
• Hypertext links: Use the text that makes sense when read out of context.
• Graphs and charts: Summarize graphs, charts, and tables using the longdesc attribute.
• Scripts, applets and plug-ins: Provide alternative content in case active features are inaccessible or unsupported.
• Tables: Make line-by-line reading sensible. Be sure to summarize each table and use appropriate titles and descriptions.
• Check your work: Use validation tools to make sure web content is accessible.