Web Accessibility

Web Content Accessibility Guidelines (WCAG) 2.1 covers a wide range of recommendations for making web content more accessible. Following these guidelines will make content more accessible to a wider range of people with disabilities, including accommodations for blindness and low vision, deafness and hearing loss, limited movement, speech disabilities, photosensitivity, and combinations of these, and some accommodation for learning disabilities and cognitive limitations; but will not address every user need for people with these disabilities. These guidelines address accessibility of web content on any kind of device (including desktops, laptops, kiosks, and mobile devices). Following these guidelines will also often make web content more usable to users in general.

WCAG 2.1 is developed through the W3C process in cooperation with individuals and organizations around the world, with a goal of providing a shared standard for web content accessibility that meets the needs of individuals, organizations, and governments internationally.

• Principles – At the top are four principles that provide the foundation for web accessibility: perceivable, operable, understandable, and robust. See also Understanding the Four Principles of Accessibility.
• Guidelines – Under the principles are guidelines. The 13 guidelines provide the basic goals that authors should work toward in order to make content more accessible to users with different disabilities. The guidelines are not testable, but provide the framework and overall objectives to help authors understand the success criteria and better implement the techniques.
• Success Criteria – For each guideline, testable success criteria are provided to allow WCAG 2.1 to be used where requirements and conformance testing are necessary such as in design specification, purchasing, regulation, and contractual agreements. In order to meet the needs of different groups and different situations, three levels of conformance are defined: A (lowest), AA, and AAA (highest). Additional information on WCAG levels can be found in Understanding Levels of Conformance.
• Sufficient and Advisory Techniques – For each of the guidelines and success criteria in the WCAG 2.1 document itself, the working group has also documented a wide variety of techniques. The techniques are informative and fall into two categories: those that are sufficient for meeting the success criteria and those that are advisory. The advisory techniques go beyond what is required by the individual success criteria and allow authors to better address the guidelines. Some advisory techniques address accessibility barriers that are not covered by the testable success criteria. Where common failures are known, these are also documented. See also Sufficient and Advisory Techniques in Understanding WCAG 2.1.

1. How to Meet WCAG 2.1 – A customizable quick reference to WCAG 2.1 that includes all of the guidelines, success criteria, and techniques for authors to use as they are developing and evaluating web content. This includes content from WCAG 2.0 and WCAG 2.1 and can be filtered in many ways to help authors focus on relevant content.
2. Understanding WCAG 2.1 – A guide to understanding and implementing WCAG 2.1. There is a short “Understanding” document for each guideline and success criterion in WCAG 2.1 as well as key topics.
3. Techniques for WCAG 2.1 – A collection of techniques and common failures, each in a separate document that includes a description, examples, code and tests.
4. The WCAG Documents – A diagram and description of how the technical documents are related and linked.