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WAI: Strategies, guidelines, and resources to make the Web accessible to people with disabilities

This is an outdated draft and should not be referenced or quoted.
The latest version is at: www.w3.org/WAI/intro/usable

[Draft] Web Accessibility and Usability

See also: Accessibility - W3C

Page Contents


[@@@ main point: provide a brief introduction to the document. state that there times when differentiation is not necessary and times when it is.]

There is significant overlap between usability and accessibility [@@requirements], and not a clear distinction between them. In most situations there is no need to differentiate between usability and accessibility, because they [approaches] are complimentary. There are a few cases when the distinction is important, such as when looking at discrimination against people with disabilities and when defining specific accessibility standards.

This document explores the relationship between web accessibility and usability in the context of standards, guidelines, and conformance. (@@It doesn't try to layout formal definitions, or draw a line between usability and accessibility.) It highlights the overlap and the benefits of combining usability and accessibility in the design of standards, websites, browsers, assistive technologies, and other web tools that are inclusive for everyone, including for people with disabilities.

Understanding Accessibility

[@@@ main points: define the scope of accessibility. explain that it has aspects specific to people with disabilities (that are usually technical), and aspects that overlap with usability.]

Accessibility is about ensuring an equivalent user experience for people with disabilities. For the web, it means that people with disabilities can perceive, understand, navigate, and interact with websites and tools, and that they can contribute equally without barriers. Accessibility is not an option, it is a human right, as recognized in the UN Convention on the Rights of Persons with Disabilities (CRPD).

Some accessibility requirements are more specific to people with disabilities; for example, they ensure that websites work well with assistive technologies such as screen readers that read aloud web pages, screen magnifiers that enlarge web pages, and voice recognition software that is used to input text. Most of these requirements are technical and relate to the coding rather than to the visual appearance of websites.

Most accessibility requirements improve usability for everyone, and especially benefit older users, people using different devices, people with low literacy or not fluent in the language, people with low bandwidth connections or using older technologies, and others.. While these accessibility requirements are general usability principles, they are included in accessibility standards because they can be significant barriers to people with disabilities. For example, [[a website that is designed so that it can be used without a mouse is good usability | being able to use a website without a mouse is good usability]], and it an accessibility requirement because people with some physical and visual disabilities cannot use a mouse at all. Thus products designed to meet accessibility requirements are more usable for everyone.

@@Accessibility is not about meeting standards; it is about [it doesn't end there].@@ shawn has wording on this]]

Understanding Usability

[@@@ main points: define the scope of usability, specifically differentiating from accessibility, e.g., whereas accessibility has technical focus, usability practice is largely about process.]

Usability is about designing products to be effective, efficient, and satisfying. While "usability" is often used as an attribute [of a product], the practice of usability is largely about following a user-centered design (UCD) process to create positive user experiences.

User-centered design (UCD) focuses on usability goals, user characteristics, environment, tasks, and workflow in designing a user interface. For example, UCD considers users' hardware, software, computer experience, task knowledge, and other characteristics in designing a website, web application, browser, and other web tool. UCD is an iterative process with well-defined methods and techniques for analysis, design, and evaluation from the first stage of projects through implementation.

Usability efforts often focus on primary user groups and [high-incident|common] user characteristics; in the past, most have not included people with disabilities.

Including Accessibility in Usability Research and Practice

[@@@ main points: explain the benefit of involving people with disabilities throughout design processes & including accessibility guidelines]

Including people with disabilities in usability research and practice has many benefits; for example:

Including accessibility guidelines along with usability guidelines [helps improves product usability for people with disabilities, as well as people without disabilities].

Usable Accessibility - Including Usability in Accessibility Research and Practice

[@@@ main points: address issues with "technical accessibility" versus usability - do UCD, including real people AND accessibility standards. @@ not about one size fits all, technical requirements give you options to make choices@@]

Usable accessibility combines usability and accessibility to develop positive user experiences for people with disabilities. User-centered design processes include both techniques for including users throughout design and evaluation, and use of guidelines to inform and evaluate designs. Thus UCD methods are an effective way to improve accessibility.

Real People

[@@@ main points: emphasize the human factor of accessibility and that it is about real people (as opposed to ticking-off checkboxes); and that developers need to learn the basics first in order to manage accessibility effectively.]

Usable web accessibility means meeting the needs of real people using the Web. An effective way to meet the needs of real people is to involve users early and throughout the design process. This helps developers understand essential basics of how people with disabilities use the Web. For example, [@@ this is not UT, but buy-in session] observing people with disabilities complete tasks on an accessible website and then struggle with the same tasks on an inaccessible website helps developers better understand accessibility barriers and solutions. [@@ this is from the motivation section... there are other benefits in involving user doc!]

[@@ maybe more here ]

Technical Standards

[@@@ main points: explain the role of technical standards for developing accessible products. [[Is this within scope???: in particular to highlight the role of techniques to provide practical guidance for specific situations @@ design of WCAG important -- eg text resizing widgets is an advisory technique, not in WCAG itself]].]

While including users with disabilities is key to making accessibility efforts more effective and more efficient, that alone cannot address all issues. Even large projects cannot cover the diversity of disabilities, adaptive strategies, and assistive technologies. That is the role of accessibility standards.

The W3C Web Accessibility Initiative (WAI) develops a set of guidelines that are internationally recognized as the standard for web accessibility:

The WAI guidelines include considerations for people with auditory, cognitive, neurological, physical, speech, and visual disabilities, including people with age-related impairments.

[[@@the adaptability aspect (notes in comments)]]

The WAI guidelines are accompanied by supporting techniques that help explain how to implement the requirements in practice. For example, a WCAG 2.0 guideline defines requirements for text alternatives and there are sufficient and advisory techniques that specify how to meet this requirement, and how to optimize accessibility for people with disabilities.

WCAG 2.0 guidelines, success criteria, and techniques are provided in the How to Meet WCAG 2.0 customizable quick reference.

Usability Techniques to Optimize Accessibility [h3 or h2?]

[@@@ main points: using usability techniques to make trade-off decisions; optimizations to meet the need of specific audiences, including adaptability approaches, are part of accessibility; still, need to ensure accessibility for all]

Usability provides effective techniques to help make design decisions. For instance, usability techniques help analyse the advantages and disadvantages of specific design features for different audiences, and help make informed decisions during design of accessibility features. [@@ should this move to "Including Accessibility in Usability Research and Practice"?]

Usability techniques also help meet the accessibility needs of different audiences because the Web is highly adaptable and allows the same content to be presented to users in different ways according to their needs and preferences. For example, websites can provide content in different colors, layouts, or presentation formats to meet the needs of particular users. Websites can even provide different content that serves the same purpose; for example, different versions of a course to help students with different learning styles to complete the same curriculum. [@@ is this needed at all?]

Working Together with Accessibility

[@@@ main points: promote coordination of related work with existing accessibility work, in particular by inviting contribution to WAI work by researchers. mention negatives of not building on existing work. differentiate broad issues of "inclusion", from accessibility for specifically people with disabilities.]

Web universality, digital inclusion, design for all, universal usability, and other such efforts focus on making the Web and other technology available to and usable by all people whatever their abilities, age, economic situation, education, geographic location, language, etc. (Whereas accessibility focuses specifically on people with disabilities, including people with age-related impairments.) Often projects focus on one specific user group; for example, developing design guidelines to optimize websites for older users. Many of the requirements of different user groups overlap with [accessibility requirements | the requirements of people with disabilities].

Coordinating related efforts with existing accessibility work supports harmonization, [@@ another good thing], and can expand research and resources in both areas. However, when efforts are not coordinated, it leads to duplication of effort and confusing or even conflicting results. For example, an extensive literature review on web accessibility for older users showed that most research and development of web design recommendations for older users did not include consideration of WAI guidelines at all, even though the WAI guidelines directly address the accessibility needs of older web users.

When developing web design guidelines and @@, researchers and @@ might identify different kinds of issues:

Coordinating with WAI

W3C Web Accessibility Initiative (WAI) provides an international forum for collaboration between industry, disability organizations, accessibility researchers, government, and others interested in Web accessibility. WAI encourages those involved in usability, digital inclusion, and others to share perspectives and participate in WAI work. For example, we provide instructions for commenting on WCAG 2.0 documents and a form for submitting WCAG 2.0 techniques.

You can share comments, research findings, and questions to WAI via the e-mail address wai@w3.org. (If you don't get a reply, it might have gotten caught in spam filters; try contacting one of the WAI staff directly.) WAI looks forward to increased collaboration among usability, digital inclusion, and accessibility efforts.

[Additional notes