Digital Accessibility Terminology
If you're new to digital accessibility, learning the basic terms is a great place to start. This guide introduces common words and acronyms used in digital accessibility. Expand a term to see its definition.
A11Y – Accessibility A shortened way to write “accessibility,” where the number 11 represents the letters between “A” and “Y.”Accessible Content that can be used by people with a wide range of abilities, including those using assistive technology, without barriers.ADA – Americans with Disabilities Act A U.S. civil rights law that prohibits discrimination against individuals with disabilities. It applies to digital services under Title II (public entities) and Title III (public-facing organizations).Alt Text – Alternative Text A brief description of an image that is read by screen readers. It should communicate the purpose or meaning of the image in context.ARIA – Accessible Rich Internet Applications A set of HTML attributes used to improve accessibility for dynamic or interactive content when standard HTML is not sufficient.AT – Assistive Technology Tools that help people interact with digital content, such as screen readers, screen magnifiers, voice input, and alternative keyboards.Captioning Text displayed with video that includes spoken dialogue and meaningful sounds, supporting users who are deaf or hard of hearing.Color Contrast The difference between text and background colors. Sufficient contrast improves readability for users with low vision or color vision differences.Decorative Image An image that does not add meaning to the content. These should be marked so assistive technology ignores them.Focus Indicator A visible outline or highlight showing which element is currently selected when navigating with a keyboard.Headings Structured titles (H1–H6) used to organize content. Proper heading use allows screen reader users to navigate content efficiently.Keyboard Navigation Using a keyboard to move through and interact with content. Accessible content must be fully usable without a mouse.Link Purpose (Descriptive Links) Links that clearly describe their destination or action, such as “View syllabus” instead of “Click here.”Perceivable The first WCAG principle. Information must be presented in ways users can perceive, such as providing text alternatives for images and captions for video.Operable The second WCAG principle. Users must be able to navigate and interact with content, including with a keyboard.Understandable The third WCAG principle. Content should be clear, predictable, and easy to understand.Robust The fourth WCAG principle. Content must work reliably with assistive technologies and across different devices and browsers.Screen Reader Software that reads digital content aloud or outputs it in braille for users who are blind or have low vision.Section 504 – Rehabilitation Act of 1973 A federal law that prohibits disability discrimination in programs receiving federal funding, including digital environments.Section 508 – Rehabilitation Act of 1973 A federal requirement that electronic and information technology used by federal agencies is accessible.Tab Order The sequence in which interactive elements receive focus when using the keyboard. It should follow a logical reading order.Transcript A text version of audio content. Required for audio-only materials and helpful for search, review, and study.UD – Universal Design Designing products and environments to be usable by as many people as possible without the need for adaptation.UDL – Universal Design for Learning An educational framework that provides multiple ways for students to access content, engage with learning, and demonstrate understanding.Usability How easy and efficient content is to use. Accessibility supports usability, but usable content is not always accessible.VPAT – Voluntary Product Accessibility Template A document vendors use to explain how their product meets accessibility standards such as WCAG.W3C – World Wide Web Consortium The international organization that develops web standards, including accessibility guidelines.WCAG – Web Content Accessibility Guidelines A set of international standards developed by the W3C to make digital content accessible. Most laws and policies reference WCAG 2.1 Level A and AA.