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.

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