Web Accessibility

This chapter presents a summary of the physiological processes that support key visual functional capabilities such as visual acuity, contrast sensitivity, and field of view. The chapter also considers some of the most common causes of visual dysfunction and their impact on the visual capabilities that are necessary for successful interaction with contemporary computer systems, particularly for access to the World Wide Web (the Web). The chapter then outlines some of the key steps that have been taken in the last few years to promote the appropriate access to the World Wide Web by users who might have restrictions in their visual functionalities, as described.

Physical actions are a fundamental aspect of using the Web. Physical disabilities can impact these actions in many ways. This chapter reviews physical disabilities affecting dexterity, the different ways people physically access the Web, and the impact of these disabilities on physical access. Although voice control is an increasingly popular alternate input method, the underlying health conditions that lead to physical impairment can often also impair an individual’s speech or sensory and cognitive abilities. Consequently, easy to use, intuitive physical controls are essential to a Web that is usable by everyone.

People with hearing loss tend to use assistive and accessible technology differently from most other groups of people with disabilities, primarily due to the fact that their hearing loss influences their communication. As a result, their degree of hearing loss is but one of many aspects of their disability, which influences their preferred assistive or accessible technology. For example, for television programs, some viewers with hearing loss may prefer to turn up the volume, while others may prefer to read verbatim captions, and others prefer to follow the program with a sign language interpreter overlay. Because of these differences, designers and providers should strive to provide accessibility for people with hearing loss across multiple dimensions—hearing loss, legal requirements, communication and cultural preferences.

People with cognitive disabilities are gaining in a long struggle for recognition of their right to control their lives. In the information society, access to the Web is essential to this control. Cognitive barriers to this access are diverse, reflecting the complexity of human cognitive faculties. Advances in supporting configurable presentation and interaction methods, and in representing the meaning as well as the form of information, will yield progress. This progress is being accelerated by increasing international awareness of the importance of cognitive access.

This chapter presents an overview of situationally-induced impairments and disabilities, or SIIDs, which are caused by situations, contexts, or environments that negatively affect the abilities of people interacting with technology, especially when they are on-the-go. Although the lived experience of SIIDs is, of course, unlike that of health-induced impairments and disabilities, both can be approached from an accessibility point-of-view, as both benefit from improving access and use in view of constraints on ability. This chapter motivates the need for the conception of SIIDs, relates the history of this conception, and places SIIDs within a larger framework of Wobbrock et al.’s ability-based design (ACM Trans Access Comput 3(3), 2011, Commun ACM 61(6):62–71, 2018). Various SIIDs are named, categorized, and linked to prior research that investigates them. They are also illustrated with examples in a space defined by two dimensions, location and duration, which describe the source of the impairing forces and the length of those forces’ persistence, respectively. Results from empirical studies are offered, which show how situational factors affect technology use and to what extent. Finally, specific projects undertaken by this chapter’s author and his collaborators show how some situational factors can be addressed in interactive computing through advanced sensing, modeling, and adapting to users and situations. As interactive computing continues to move beyond the desktop and into the larger dynamic world, SIIDs will continue to affect all users, with implications for human attention, action, autonomy, and safety.

Between 2015 and 2050, the proportion of the world’s population over 60 years will nearly double from 12 to 22%. Maintaining a high quality of life for these people has become an important issue throughout the world. The Web has been shown to have a positive experience on the quality of life and well-being of older adults, by assisting them to maintain an independent living. However, many older adults seem to shy away from the Web due to various problems they experience when interacting with the Web. To understand the nature of these problems, this chapter presents the functional impairments and the attitudes that might contribute to older adults’ hesitation of utilising the Web. This chapter then discusses the changes that happen with age and their effects on Web interaction. It then moves to the standards surrounding Web accessibility, more specifically WCAG, and how they assist older adults. Finally, it discusses activities that older adults perform on the Web.

This chapter introduces speech and language from a clinical speech and language therapy perspective. It describes key challenges that can impact speech and language with a focus on the needs of individuals with aphasia, an acquired language disorder. The specific impact that aphasia may have upon Web accessibility is discussed with reference to existing work which illuminates what we currently do and do not know about speech, language and Web accessibility. The authors provide guidance for accommodating the needs of users with aphasia within the design of Web interactions and propose future directions for development and research.

This chapter introduces inclusive writing and how to incorporate it into research. We give general guidelines on language choice and suggestions on writing for and about specific user groups. However, language is constantly evolving. Preferred language for writing about people with disabilities changes over time, and with context, and can be a source of disagreement even within a user group. The inclusive writing approach proposed here covers three key points: use the included terminology and considerations as a starting point; verify language choices and other assumptions through feedback with participants; and strive for respect in all research interactions. The chapter also explores how careful thinking about language can make an entire research project more accessible and inclusive.

Involving users in the design and evaluation of websites is one of the keys to ensuring they are accessible to as wide a range of people as possible. In this chapter, we present the core barriers and solutions that are often encountered by participants in user research activities that are undertaken as part of modern user-centred design processes. We close the chapter with a discussion of future areas of research around measurement of accessible user experiences and a short list of key things to remember when undertaking user research with people with disabilities.

While discussing how government, charities and companies can work together, this chapter particularly describes how researchers can work with people with disabilities and disability organisations to create more inclusive research. It addresses issues for people working on general research that need to address the needs of real people as well as research focusing on disability. Ultimately, the aim should be to incorporate people with disabilities as participants and stakeholders in all areas of research.

The past few years have seen tremendous development in web technologies. A range of websites and mobile applications have been developed to support a variety of online activities. The ubiquitous nature and increasing complexity of technology mean that ensuring accessibility remains challenging. Accessibility evaluation refers to the process of examining a product and establishing the extent to which it supports accessibility through the identification of potential barriers. While accessibility guidelines can guide the development process and automated evaluation tools can assist in measuring conformance, they do not guarantee that products will be accessible in a live context. The most reliable way to evaluate the accessibility of a product is to conduct a study with representative users interacting with the product. This chapter outlines a range of methods which can be used to ensure that a product is designed to meet the requirements and specific needs of users, from the ideation phase to the design and iterative development. The strengths and weaknesses of each method are described, as well as the primary considerations to ensure that the results of a study are reliable and valid, and also participants are treated ethically. This chapter concludes with a discussion of the field as well as an examination of future trends such as how data from user studies can be used to influence the design of future accessibility guidelines to improve their efficacy.

To ensure that you are conducting research to the highest scientific standards, data collection and analysis procedures should be robust, well-described, and open to scrutiny. In principle, this may sound straightforward; in practice, it is very hard to achieve. Here we examine what it means, and what it involves, for Web accessibility researchers to make computational research methods reproducible—such that the data and methods are available to and usable by others—and sustainable—such that they continue to be available and usable over time.

The World Wide Web, the Web, is technically a family of open standards that defines the protocols and formats needed for the Web to function. These technical standards are the backbone of Web accessibility. They define critical accessibility features of Web technologies, as well as interoperability with assistive technologies. At the same time, these technical standards are rapidly evolving as the Web continues to expand in volume and in functionality, as different industry and technology sectors continue to converge onto the Web, and as our expectations for the Web continue to expand. Recent advances in Web technologies include enhanced support for mobile content and applications, real-time communication, immersive environments, multimedia, and automotive systems. Concurrently, Web-based applications are increasingly making use of advances in Artificial Intelligence (AI), Internet of Things (IoT), and Open Data. While such technological advances provide immense opportunities for the inclusion of people with disabilities, they require dedicated efforts to understand the diverse accessibility needs and to develop clear accessibility requirements for designers and developers of digital content, tools, and technologies for desktop and mobile devices. The World Wide Web Consortium (W3C) is the leading standards body for the Web and has a long history of commitment to accessibility. The W3C Web Accessibility Initiative (WAI) utilizes a multi-stakeholder consensus approach to pursue the goal of ensuring accessibility for people with disabilities on the Web. This includes designing and implementing particular accessibility features in core Web standards such as HTML and CSS, as well as developing and maintaining a set of Web accessibility guidelines, which are recognized internationally by business and government. This participatory effort involving representation of people with disabilities, industry, research, public bodies, and other experts promises to address evolving trends on the Web to help ensure accessibility for people with disabilities.

This chapter provides an overview of law and policy concepts related to web accessibility. Laws and policies can include a broad range of methods and documents, including national, regional, and provincial statutes, national and more local regulation, case law, policy, enforcement action, as well as treaties and human rights documents. The chapter continues by discussing the coverage of these laws and policies: what types of organizations, what types of disabilities, and what types of content are covered by the laws? Technical standards, user involvement, and transparency are also discussed. The concluding sections discuss future directions in web accessibility law and policy, what is currently needed, and some of the actions that we can individually take as members of the accessibility community.

The focus of this chapter is the accessibility of the websites of postsecondary/higher education institutions. We will critique the ability and willingness of these institutions to respond to anti-discrimination and equality legislation by addressing the access needs of the increasing number of disabled students who are enrolling in postsecondary/higher education institutions. This critique will entail a review of the range of approaches that institutions employ to make their websites accessible; a case study of “best” accessibility practice in the field and a consideration of the challenges and opportunities that institutions face in seeking to improve website accessibility.

Access to the Web for people with cognitive, language, and learning differences and limitations is widely recognized as important and becoming more important as Web content and Apps become ubiquitous. Yet progress has been slow, as indicated by limited support for cognitive accessibility within the Web Content Accessibility Guidelines process. How can this progress be accelerated, and how can research contribute to the increase in cognitive accessibility that is needed?

While the field of accessibility of websites, software, and apps has primarily dealt with the technical aspects of the products themselves, inclusion deals with the experience of people using these technology products as part of their lives. Inclusion means that the widest range of users are able to have an experience with the product that helps them to be part of society and commerce. This chapter discusses the inclusion of people from a variety of marginalized groups, on the internet and web, in employment, and in the development of commercial web and app products. It covers some of the history of disability inclusion, and how changes in user and employee expectations, and changes in technology, will impact inclusion for people with disabilities going forward.

Over the last three decades, the Web has become an increasingly important platform that affects every part of our lives: from requesting simple navigation instructions to active participating in political activities; from playing video games to remotely coordinate teams of professionals; from paying monthly bills to engaging is micro-funding activities. Missing on these opportunities is a strong vehicle of info-, economic-, and social-exclusion. For people with disabilities, accessing the Web is sometimes a challenging task. Assistive technologies are used to lower barriers and enable people to fully leverage all the opportunities available in (and through) the Web. This chapter introduces a brief overview of how both assistive technologies and the Web evolved over the years. It also considers some of the most commonly used assistive technologies as well as recent research efforts in the field of accessible computing. Finally, it provides a discussion of future directions for an inclusive Web.

The purpose of this chapter is to describe some of the issues related to creating accessible documents and publications. Publications include both formal publications such as those created by publishing houses and those created informally such as a corporate organization’s annual report. Until the last few years, most organizations relied heavily on the Portable Document Format (PDF) and this is gradually being replaced by the ePUB format as the accepted international standard. However, issues still exist in the best method to create these documents, how accessibility is assessed, and how to ensure accessibility is maximized for users. This chapter also looks at some of the new technology in document creation, remediation and assessment.

Authoring tools play two very critical roles in Web accessibility. They offer a powerful mechanism for promoting the creation of accessible Web content. They are also the key to ensuring that people with disabilities are not just consumers, but also producers of Web content, an essential criterion for full participation in our Web-mediated society. This chapter discusses the important role that inclusively design authoring tools play in achieving equitable participation in the complex adaptive system that is the Web.

Web applications have provided a good deal of information that is dynamically rendered to users in accordance with their needs. The continuous evolution of web technologies has enhanced the flexibility of interactions with increasingly varied and resourceful web interfaces (i.e. rich interfaces) that support dynamic web content. However, the increase in web interactivity has created accessibility barriers, because users of Assistive Technology (AT) tools may not be aware of the web’s dynamic behaviour and its available controls. The goal of this chapter was to clarify technical factors, as well as to address the main concerns and their outcomes that developers have to deal with, and provide a brief account of current trends in research on this subject. For this reason, this chapter describes the main mechanisms used in web applications that are responsible for providing the dynamic content. In addition, there is a discussion of questions regarding the accessibility of the web resources that form the dynamic content.

Scientific documents are a very specialised type of literature not only in terms of their topics and intended audience, but also in terms of their content and how it is presented. They generally use highly topical vernacular, mathematical formulas, diagrams, data visualisations, etc. While any single one of these features on its own poses a considerable accessibility problem, their combination makes the accessibility of scientific literature particularly challenging. However, with nearly all aspects of learning, teaching, and research moving to the web, there is a need to specifically address this problem for science on the web. In this chapter, we present an overview of the main challenges that arise when making scientific texts accessible. We will particularly concentrate on the accessibility problem for scientific diagrams and discuss the more common techniques for making them accessible via screen-reading, sonification and audio-tactile presentation. This chapter gives an overview of the current state of the art, sketches some of the technical details on how to create accessible diagrams and closes with some open research questions.

Math accessibility work dates back to the 1990s, but these efforts have accelerated rapidly in the last 5 years. It has moved from research into widely used systems that include JAWS, NVDA, VoiceOver, and TextHELP. The current systems convert MathML into speech and braille, and allow the users to navigate expressions for better comprehension. Further work on better semantic speech that uses page content or other clues to determine the meaning of the notation and how it should be spoken is ongoing. Work on accessible typed input, braille input, speech input, and accessible ways of doing math (not just reading it) is also underway. Beyond equations, the research on audio and tactile methods of presenting plots and charts has also been performed, and is being incorporated into commonly used software.

The concept of universal usability brings practical purpose to web accessibility efforts by focusing on enabling diverse populations to successfully and independently use the web for meaningful goals. Design patterns have emerged as a means to capture and standardize research-derived knowledge in the accessible interface and interaction design through presenting definitions and examples of how commonly used interface components can be designed with accessibility in mind. A design system and code library with patterns that incorporate accessibility features is a powerful tool for ensuring people with disabilities benefit from new technologies. Additionally, patterns benefit general usability by improving the learnability and memorability of interaction patterns. Guidelines that encourage or enforce standard interaction patterns, like Apple’s Human Interface Guidelines (Apple in Human interface guidelines, 2018), improve user experience and in turn, increase loyalty behaviors such as repurchase and referrals (Hoisington and Naumann in Qual Prog 36(2):33–41, 2003). In this chapter, we reaffirm the relationship between accessibility and universal usability, reflecting on developments since the Universal Usability chapter in the first edition of this book (Horton and Leventhal in Universal usability. Springer, 2008). With today’s more mature technology platform and profession, we explore the use of accessible design guidelines and patterns to provide interactions that are usable by everyone.

Multimedia content is growing at an increasing pace. Making this content accessible to people with impairments is not only paramount but also a growing challenge in itself. Access services for people with visual or hearing impairments have been studied and refined over the last years, resulting in standards and laws to ensure that minimum amounts of accessible content are produced. Professional content producers have the knowledge and skills required to do so. However, individuals creating multimedia content to publish on the Internet usually lack both. In this chapter, we review existing access services, comprised of subtitles, sign language and audio descriptions. We complement this with a summary of research efforts that could assist both in the production and consumption of access services. Finally, we discuss how emerging technologies and techniques, like machine learning or crowdsourcing, can help us tackle the sheer amount of access services that need to be created to ensure all have equal access to produced content.

The objective of Web accessibility evaluation is to verify that all users are able to use the Web, this means that they can perceive, understand, navigate, and interact with it (Henry 2018a). Since the manual verification of the fulfilment of guidelines that specify accessibility requirements can often turn out to be difficult and cumbersome, it is crucial to have appropriate computer tools available to assist this activity. There exist numerous applications that perform diverse types of automatic accessibility evaluations. On the other hand, on-site and remote evaluations with users can also be supported by specific tools. Even manual evaluations may be supported by crowdsourcing-based tools. All these innovations may have crucial importance in the advancement of Web accessibility. This chapter studies the need for tools in this field, reviews the main characteristics of the tools used for Web accessibility evaluation, and reflects upon their future.

This chapter starts by depicting how the topic of web accessibility metrics was in 2011, analyses what has happened since, and discusses the challenges that accessibility metrics face today. More specifically, we review a variety of metrics and a quality framework for metrics based on validity, reliability, sensitivity, adequacy and complexity. We then describe what new metrics were defined and how metrics have been used in the last 7 years, which range from assessments of accessibility awareness, of accessibility progress, to in-depth analyses within the banking sector, in country-based and continent-based assessments. We illustrate metrics that use new kinds of data, like human judgements or questionnaires, that in some case are used to deal with validity and reliability of metrics. The chapter ends with a discussion of the challenges ahead.

Cognitive Accessibility is an important aspect of Web accessibility addressing a considerably large number of users and showing a high impact on general usability. Cognitive accessibility has been on the agenda in Web accessibility since its beginning but the body of R&D is much smaller and also guidelines, standards, techniques, and tools are vaguer as well as addressed at a lower priority. The recent focus on cognitive accessibility in W3C/WAI changes the situation. This chapter discusses the state of the art and the different domains, where R&D is needed for guidelines and standards, inclusion and participation of end users, take-up of the digital potential in service provision and new tool development based on user tracking/understanding and Artificial Intelligence (AI). We conclude by proposing a new concept of user involvement and a framework for R&D supporting the integration of profiling, annotating, adapting and translating content for personalized Cognitive Accessibility and using/adapting proven and stable HCI concepts.

In this chapter, we discuss methods and tools for adapting user interfaces to make them more accessible. We introduce the problem of user interface adaptation and characterize different techniques to be adapted to the user interface. We show that there is a broad range of methods and tools to transform existing interfaces to make them accessible. We describe such approaches by grouping them in two types of solutions: those that provide built-in adaptation mechanisms for the application and those which are external to the application.

“Transcoding for Web accessibility” is a category of technologies to transform inaccessible web content into accessible content on the fly. It was invented to help people with disabilities access inaccessible web pages without asking the content authors to modify their pages. It does this by converting the content on the fly in an intermediary server between the web server and the web browser. The technology has matured along with voice browsing technology from circa 1992 and was actively used in the 2000s. In this chapter, we will first cover the history of the transcoding technologies, and then introduce technical details of these transcoding systems. Finally, we discuss future directions and technical problems.

Nowadays, being excluded from the web is a huge disadvantage. People with dyslexia have, despite their general intelligence, difficulties for reading and writing through their whole life. Therefore, web technologies can help people with dyslexia to improve their reading and writing experience on the web. This chapter introduces the main technologies and many examples of tools that support a person with dyslexia in processing information on the web, either in assistive applications for reading and writing as well as using web applications/games for dyslexia screening and intervention.

People with vision impairments typically use screen readers to browse the Web. To facilitate nonvisual browsing, web sites must be made accessible to screen readers, i.e., all the visible elements in the web site must be readable by the screen reader. But even if web sites are accessible screen reader users may not find them easy to use and/or easy to navigate. For example, locating the desired information may require a tedious linear search of the webpage that involves listening to a lot of irrelevant content. These issues go beyond web accessibility and directly impact web usability. Several techniques have been reported in the accessibility literature for making Web usable for screen reading. This chapter is a review of these techniques.

Difficulty accessing digital educational material in the fields of science, technology, engineering, and mathematics (STEM) hinders many students from receiving an education according to his/her preferences and fully enjoying the opportunities offered by our technology-enhanced society. Web resources enhance the delivery of STEM content by offering interactive and visual models, dynamic content, videos, quizzes, games and more. STEM content can be delivered in several ways including visually, vocally, or through a 3-D printed Braille bar or other assistive technology. In this chapter, we focus on the accessibility of STEM Web content for students with disabilities who are prevented from fully accessing digital visual resources, precluding a fully inclusive education. This chapter offers an overview of the state of the art of accessibility of STEM content on the Web, focusing especially on the experience of blind students. Existing issues and the authors’ opinions in the field are aimed at motivating future research and development.

Wayfinding is a fundamental ability for daily living of people with disability. People with visual impairments have difficulty to find and follow an appropriate route, and wheelchair users need to find an accessible route without gaps or stairs. Wayfinding systems allow them to navigate indoor and outdoor environment seamlessly, and assist their daily mobility to schools, offices and any other places they are interested in. This chapter will focus on introducing technologies to enable such wayfinding systems to assist people with disabilities.

Computing devices have evolved from machines that fill a room, to portable and mobile devices, and now to devices that are worn on our own bodies. Wearable computing devices provide new opportunities for supporting individuals with disabilities via environmental context sensing and ubiquitous input and output. However, designing wearable computing devices to support people with disabilities requires careful design of features, the wearable device itself, and the input and output methods used. This chapter offers an overview of contemporary trends in wearable computing devices for people with disabilities.

Tangible interfaces are a method of computer interaction that supports communication through the human kinesthetic system, a network of sensory inputs and outputs that allow the body to perceive the physical world. By leveraging the physical properties of objects identified by the kinesthetic system, a tangible interface makes it possible to interact with computational information more naturally than the traditional computer mouse and keyboard. Tangible interaction enables individuals with a range of abilities to use technologies in the same way. In this chapter, we explore the role of tangibility as an assistive technology. We summarize three projects completed by the authors that demonstrate novel ways of deploying tangible interfaces.

Mobile devices are the tools of the trade to access services and contents on the Internet, already surpassing their desktop counterparts. These gadgets are always available and provide access to social networks, messaging, games, productivity tools, among many others. Accessing the Web with mobile devices, either through a browser or a native application, has become more than a perk; it is a need. Such relevance has increased the need for provide accessible mobile webpages and (Web and native) applications; failing to do so would exclude people with different abilities from a world of opportunities. In this chapter, we focus our attention on the specific challenges of mobile devices for accessibility, and how those have been addressed in the development and evaluation of mobile interfaces and contents. We finish with a discussion on future directions in the field, that outlines the need to learn from the fast emergence of a mobile world, and be prepared for the impact of other upcoming technologies.

This chapter presents an introduction to digital fabrication and the exciting opportunities it offers in the accessibility and assistive technology domain. Digital fabrication tools are more efficient and accessible than manual fabrication tools, allowing for efficient and affordable creation or modification of existing assistive technologies, or novel solutions. This chapter provides an overview of relevant digital fabrication tools (with an emphasis on 3D printing technology) and current online communities to share ideas and designs, and discusses exciting research and practitioner contributions that leverage 3D printing. The chapter concludes with the author’s recommendations for how to successfully apply this technology in accessibility projects and areas for future inquiry.

IoT enables the worldwide connection of heterogeneous things or objects, which can hence interact with each other and cooperate with their neighbors to reach common goals, by using different communication technologies and communication protocol standards. IoT and related technologies can increase or reduce the gap among people. In this respect, this chapter aims to highlight the virtuose use of the IoT paradigm by providing examples of its application for enhancing universal access in different fields.

Accessibility has, at its heart, the aim of removing developer and content creator preconceptions as to the technology, people, working environment, and use their systems support. The move to mobile has been nothing but positive for the accessibility of people with a visual disability. Similarly in the next 10 years as the Web becomes a utility, imbedded—embedded and invisible—and as wearables, sensors and the Internet of Things (and the Web, IoW) become more prevalent accessibility will be even more crucial. As the Web becomes more seamless, we will need to look for new ways to convey information in many different environments, and here lessons from accessibility will contribute. We have seen over the last 10 years the expansion from physical and sensory disability through cognitive and ageing to inclusion, and situational impairments. Over the next 10 years, our understanding of assistive technology will change because we cannot build for the many combinations of interactions, technologies, environments and users then assistive technology will just become ubiquitous. More attention will be paid to previously under-represented areas such as cognitive and autism spectrum conditions as well as those surrounding comprehension and people with learning difficulties. These groups have often been overlooked in the past; this is changing and will change significantly in the next 10 years. So in 10 years, we predict that new solutions for emerging technologies will be required, that accessibility research will focus more on cognitive and learning spectrum conditions, that access technology will become more ubiquitous, and that this ubiquity will require automated tooling created by experts to assist in the removal of barriers at scale.