There are many great tools and resources available to help people with disabilities access information or content on the web. However, because many of these tools are produced by different developers, there is the potential for these tools to conflict with one another or for the development process to become overly complicated.
The User Agent Accessibility Guidelines form part of a series of accessibility guidelines published by the W3C Web Accessibility Initiative (WAI) to help developers design user agents that make the web more disability friendly. The present version of the User Agent Accessibility Guidelines (UAAG), UAAG 2.0, was released in 2015, but these guidelines will continue to be revised and updated for years to come.
The term “user agents” includes a wide range of useful tools including browsers, plug-ins and browser extensions, media players, readers, and any other type of application that renders web content. Any user agent that follows UAAG 2.0 will improve accessibility through its user interface as well as its ability to communicate with other technologies, including assistive technologies.
The UAAG focus on improving accessibility for people with a wide range of disabilities, including people with visual, auditory, physical, speech, cognitive, language, learning, or neurological impairments, as well as disabilities related to aging. The goal of UAAG 2.0 is to ensure that all users, regardless of ability, have equal control over the environment they use to access the web.
As some users could have more than one disability, this can lead to situations where the needs of different disabilities can conflict with one another. One of the goals of the UAAG is to define configuration preferences that ensure a feature designed to improve accessibility for one user doesn’t interfere with the needs of another user. UAAG 2.0 includes requirements that promote clear documentation and ease of configuration to avoid overwhelming users with an excess of configuration options.
The UAAG and other similar resources also provide benefits to accessibility experts, policy makers, and other involved parties by providing an effective reference for improving the accessibility of user agents. The guidelines can also help developers of assistive technologies by clearly defining and explaining what kind of information and control an assistive technology can expect from a user agent that follows UAAG 2.0.
To meet the needs of a diverse audience, the UAAG provides three layers of guidance: overall principles, general guidelines, and testable success criteria.
Under each of the five principles is a set of specific guidelines that provide the framework to help developers and authors understand the objectives for success criteria so they can be more easily implemented
Under each guideline is a set of testable success criteria that can be used wherever conformance testing is required, including design specification, purchasing, regulation, and contractual agreements. Each success criterion is assigned a level, which have been designed to meet the needs of different groups and different situations: A (minimum conformance), AA (recommended conformance), and AAA (advanced conformance)
Ultimately, UAAG 2.0 belong to a suite of guidelines that are useful for progressing accessibility for the benefit of everyone — those with disabilities as well as the developers who create accessibility software and technology and depend on clear frameworks.