Designers conceive and construct the world we live in: architects draw buildings, product designers draw chairs, bikes and other tools we use every day, and web designers determine how websites should look and function. These designers, in the broad sense, design the interface of how we interact with the world and the society around us.

This is a big challenge, because people are very diverse, and designing an interface that works for everyone is difficult. Accessibility (often shortened to a11y: “a”, then 11 letters, and then a “y”) is the discipline in design that tries to match those interfaces to all, or at least to as many people as possible, and to maximise the match of people’s interactions with the world around them.

Accessibility has long been viewed from the perspective of disabilities as a personal attribute: experiences and interactions were designed so that people with a lack of a physical ability resulting from an impairment could still perform an activity in the manner of, or within the range considered for, a human being. Buildings are made accessible to wheel chairs, movies are subtitled so that deaf people can watch them and websites are designed so that they can be used by the blind.

A more modern look on accessibility goes beyond the aspect of impairments, and takes into account the whole context in which humans interact with the world around them. A mismatch between a persons abilities and an interaction interface can not only be a result of a physical impairment, but also of their cognitive abilities, some temporary disabilities (like injuries), or through characteristics of the environment people find themselves in.

Microsoft’s Inclusive Design methodology embraces this wider approach to disabilities and accessibility. The following diagram illustrates perfectly how disabilities are not personal attributes, but can also be temporary and situational.

Source: Microsoft Inclusive Design Toolkit

Source: Microsoft Inclusive Design Toolkit

This approach shows that accessibility is not a niche discipline, and that it is not just a matter of how to design things so that people with permanent impairments can also use a product or service. A tool that can be used single handedly does not only benefit people with amputated upper extremities, but also benefits people with temporary arm or hand injuries, and parents carrying sleeping newborns in their arm.

The US Census Bureau estimates that 26.000 people in the US suffer a permanent loss of upper extremities each year, while the yearly number of people with temporary injuries of hands and arms was estimated at 13 million. On top of that, the number of people with situational impairments amounts to 8 million. So the number of people benefitting from a design that allows single hand use of a tool does not run in the thousands, but in the millions.

Similarly, designing with the constraint of making screens usable for people with visual impairments for example, resulted in high-contrast screen settings. These have proved to be very handy for anyone trying to read something from a screen in bright sunlight.

Web accessibility

The move from analog publications, like printed books, magazines and newspapers, to digital ones created big opportunities for accessibility, especially for people with visual impairments. Reading from a screen allows users to adjust settings like the contrast and font sizes, and allows readers to zoom in into documents.

The move to digital also meant the advent of screen readers: a form of assistive technology that renders text as speech (or braille output), which can help people with visual impairments, illiterate people and people with learning disabilities.

But the move from analog to digital meant more than just going from printed text to text on screens. Personal computers and their operating systems are inherently interactive: as a user, you navigate the file system, open, edit, close and move documents, perform searches, install and remove applications, … Designing a graphical user interface for all these actions, and the real world hardware to interact with it were big challenges on their own. Making these interfaces accessible is a continuous and ongoing battle.

The World Wide Web added to the possibilities for accessibility. Hypertext Markup Language (HTML), the language web pages are written in, was designed with accessibility in mind. As you’ll see in the HTML 101 and Accessible HTML modules, HTML contains many features that can help people using assistive technology, like screen readers, to navigate, read and interact with the content of web pages.

But the move to online and digital also posed new challenges for accessibility. Some of these are related to technology. For example, online content that requires loading tens or even hundreds of megabytes is not very accessible, especially not in areas were mobile connections are the main access to the web and which might be slow and expensive.

Another challenge is the use of a computer mouse to operate a computer. People with physical impairments might not be able to use a mouse, the mouse can be malfunctioning, or people might not possess a computer mouse at all. So alternative ways of interacting with an operating system and the web need to be provided for an accessible experience. Keyboard interaction is an important part of that: one principle of accessible interaction is that everything that can be performed by using a computer mouse should also be possible using the keys on a keyboard only.

Since Apple introduced its first iPhone, smartphones have become ubiquitous world wide. This is yet another challenge for the accessibility of web pages: they should look and function well on small screens in portrait mode, and the interactivity needs to be operable with touch gestures.

Accessibility standards

The World Wide Web Consortium, the main international standards organisation for the internet, is maintaining a set of accessibility guidelines for the web with the Web Content Accessibility Guidelines (WCAG).

Version 1.0 of WCAG was released in 1999 and consisted of 14 guidelines. Version 2.0 was released in 2008 and adopted 4 principles of accessibility, also called the POUR principles of accessibility: