Accessibility refers to principles in software development that ensure information and interaction with the interface is usable for people with disabilities or individuals under specific conditions or circumstances.
Accessibility (a11y) measures how easily people with disabilities or impairments can use a computer system, including the both software and hardware.
Why it's important
- An interface designed with accessibility in mind is an interface that everyone can use equally. As technologies evolve and develop, they are used by more and more people all over the world.
- Accessible user interface can provide text-to-speech conversion, and output to specialized braille equipment for visually impaired users. Media like images and videos can also be accessible. An example of accessible media is subtitles, which can make films accessible to people with hearing impairments.
- Accessibility isn't just about making UI usable for people with disabilities, but also about making user experience more comfortable in different conditions (bright sun, noisy environment, limited movement, suddenly discharged wireless mouse, etc.).
Types of disabilities to consider when designing and developing an interface
- Visual impairment: users with this disability may find it challenging to read text that is too small or not displayed with high contrast, or to interpret complex graphics and diagrams that are not designed with accessibility in mind.
- Auditory impairment: users with this disability may face challenges accessing audio content that isn’t provided with closed captions or transcripts, or using products that rely solely on audio cues to convey information.
- Mobility impairment: users with this disability may find it difficult to navigate and interact with products that require precise mouse movements or rapid keyboard inputs, or that don’t provide support for assistive devices such as screen readers.
- Cognitive impairment: users with this disability may struggle to understand complex language or perform multiple tasks at once, or may experience sensory overload due to excessive animation or flashing colors. Products that are not designed with accessibility principles in mind could exacerbate these challenges.
- Aging population: as people age, they may experience a decline in visual acuity, auditory acuity, motor skills, or cognitive ability.
Main terms and definitions
- Accessibility is abbreviated as a11y. This is a so-called numeronym, where the number in the middle refers to the number of letters the word contains between the first and last letter. This abbreviation technique is mostly used in the software development community.
- WAI-ARIA or Accessible Rich Internet Applications is a suite of web standards that defines ways to make content and applications accessible to people with disabilities.
- ARIA in HTML is a technical specification on the use of special HTML attributes (prefixed with
aria-) that help assistive technologies like screen readers navigate and interact with the interface.
- WCAG or Web Content Accessibility Guidelines are a set of recommendations for making web content more accessible that are developed by a separate working group within the W3C.
- ARIA Live Region is a dynamically changing part of the interface such as chats, progress bars, alerts, etc. These are the perceived areas of the pages that are usually updated as a result of an external event when the user has focused somewhere else. The main purpose of these areas is to tell screen readers how to properly handle content changes that are not necessarily user-dependent.
- Screen Readers (VoiceOver on Mac and iOS, TalkBack on Android, NVDA or JAWS for Windows) are assistive technology applications designed for the blind and visually impaired. These applications render text, image content, or interface elements as speech, and provide sound and vibration feedback.
- Index of ARIA Design Pattern Examples includes the indexes of example implementations of ARIA design patterns included in WAI-ARIA Authoring Practices 1.1.
- The A11Y Project is a community-driven project where participants share best practices and ways to improve digital accessibility.
- WebAIM or Web Accessibility in Mind is a non-profit organization from the University of Utah, USA. It is actively involved in the development of standards, techniques and approaches for improving accessibility, and also provides accessibility consulting and training for the web community.