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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This is an outdated draft and should not be referenced or quoted.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 Working Together

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There is significant overlap between usability and accessibility guidelines, and not a clear distinction between them. In most situations there is no need to differentiate between usability and accessibility, because their goals 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 encourages increased communication and coordination between accessibility and usability research and practice in the design and development of standards, guidelines, websites, browsers, assistive technologies, and other web tools to make them accessible to people with disabilities, inclusive, and usable for everyone.

Understanding Accessibility

Accessibility is about ensuring an equivalent user experience for people with disabilities. For the Web, accessibility means that people with disabilities can perceive, understand, navigate, and interact with websites and tools, and that they can contribute equally without barriers. Access to information and communications technologies is a basic human right as recognized in the UN Convention on the Rights of Persons with Disabilities (CRPD)(links off WAI website). See Accessibility - W3C(links off WAI website) for an introduction to web accessibility.

[Although there are many benefits to accessibility,] some accessibility guidelines primarily meet the needs of 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 guidelines are technical and relate to the underlying code rather than to the visual appearance.

Most accessibility guidelines also improve usability for everyone, and especially benefit older users, people using different devices, and others such as people with low literacy or not fluent in the language, and people with low bandwidth connections or using older technologies. While these accessibility requirements are also 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 developed so that it can be used without a mouse is good usability; and use without a mouse is an accessibility requirement because people with some physical and visual disabilities cannot use a mouse at all. Products designed to meet accessibility requirements are more usable for everyone.

Understanding Usability and User-Centered Design (UCD)

Usability is about designing products to be effective, efficient, and satisfying. Usability is part of the human-computer interaction (HCI) research and design field (which is much broader than usability testing). A key aspect of usability is following a user-centered design (UCD) process to create positive user experiences. Usability and human-centred design for interactive systems are covered in ISO 9241 Ergonomics of Human System Interaction.

User-centered design (UCD) focuses on usability goals, user characteristics, environment, tasks, and workflow in designing a user interface to meet user requirements. 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.

Including Accessibility in Usability Research and Practice

Usability efforts often focus on primary user groups and common user characteristics; in the past, many have not included people with disabilities. WAI encourages usability research and practice to fully incorporate people with disabilities. The many benefits include:

Involving Users in Web Projects for Better, Easier Accessibility introduces some basics. Just Ask: Integrating Accessibility Throughout Design(links off WAI website) provides detailed guidance on incorporating accessibility in user-centered design.

Usable Accessibility - Including Usability in Accessibility Research and Practice

Usable accessibility combines usability and accessibility to develop positive user experiences for people with disabilities. User-centered design processes (UCD) include both techniques for including users throughout design and evaluation, and using guidelines for design and evaluation. UCD helps make informed decisions about accessible design. Thus UCD methods are an effective way to improve accessibility in websites and web tools.

Real People

The goal of web accessibility is to make the Web work well for people, specifically people with disabilities. While web accessibility standards are an effective tool to help meet that goal, meeting standards itself is not the end goal. People with disabilities effectively interacting with and contributing to the Web is the end goal.

To make the Web work well for people with disabilities, designers and developers need to understand the basics of how people with disabilities use the Web. Following UCD to involve people with disabilities throughout design processes and involve users in web accessibility evaluation helps design solutions that are effective for users and for developers. (See also: How Involving Users Early Helps section.)

Technical Standards

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 WAI guidelines are stable technical standards for meeting user requirements that apply broadly across technologies and situations. Along with the guidelines are techniques and other supporting resources that provide details on how to meet the guidelines (and thus the user requirements) in specific situations.

Working Together with Accessibility

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 the requirements of people with disabilities.

Coordinating related efforts with existing accessibility work supports international harmonization and interoperability, 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(links off WAI website) showed that most research and development of web design recommendations for older users did not consider WAI guidelines at all, even though the WAI guidelines directly address the accessibility needs of older web users.

When researchers, designers, and developers, and others are developing web design guidelines, they 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.

WAI looks forward to increased collaboration among usability, digital inclusion, and accessibility research and practice.