Digital Accessibility Experts, Australia.
Plain-English definitions of 111+ digital accessibility terms covering WCAG 2.2, assistive technologies, disability groups, design and code, compliance and audit process. Every entry cross-references the tools, services and WCAG success criteria you can act on next.
This glossary defines 111 digital accessibility terms in plain English, grouped across six categories: WCAG and standards, assistive technology, disability, design and code, compliance and legal, and process and delivery. Every term links to the relevant ExceedAbility tool, service or WCAG success criterion, so you can move from definition to action in one click. Use the WCAG Criteria Search for rule-level detail, the tools page for self-service resources, or contact our team to discuss applying any of these to your product. Free, no signup, maintained by an Australian accessibility delivery partner.
Last reviewed: May 2026
Showing all 111 terms.
The highest WCAG conformance level. Useful as an aspirational target for specific user groups (e.g. cognitive accessibility, sign language interpretation) but not generally required by law because some content cannot practically meet it.
Tools and methods that supplement or replace speech, including communication boards, speech-generating devices and dedicated apps such as Proloquo2Go and TouchChat. Used by people with speech impairments, motor neurone disease, autism or aphasia.
A structured assessment of a digital product against WCAG or another accessibility standard. ExceedAbility audits combine automated scanning, expert manual review and assistive-technology testing, and produce findings with severity ratings, evidence and prioritised remediation guidance.
A staff member outside the dedicated accessibility team who advocates for accessibility within their squad, business unit or product. Champion networks are a low-cost way to scale accessibility capability across an organisation.
Standardised document reporting how a product or service conforms to specific accessibility standards (WCAG, EN 301 549, Section 508). The VPAT is the most widely used ACR format and is routinely requested in government procurement.
A public document declaring an organisation's accessibility commitments, current conformance level, known limitations and how to report problems. Required by the Australian Digital Service Standard for public-facing government services.
WCAG terminology meaning a technique actually works with the assistive technology users have, not just that it is theoretically conformant. Custom widgets must be tested across the major screen readers, not assumed compliant from ARIA markup alone.
The browser's internal representation of a page that is exposed to assistive technology. Built from the DOM plus ARIA, then consumed by screen readers and other AT. What you see in the accessibility tree is what AT users get.
Canadian federal law in force since 2019 that requires federally regulated organisations to identify and remove accessibility barriers. Sets a national goal of a barrier-free Canada by 2040 and is enforced by Accessibility Standards Canada.
A disability that develops during a person's lifetime through injury, illness or age, rather than being present from birth. Most disability is acquired; design assumptions that disabled people are always lifelong assistive-technology experts are usually wrong.
United States civil rights law prohibiting discrimination on the basis of disability. Title III is increasingly applied to websites and digital services, with WCAG 2.1 AA the de facto benchmark cited in settlement agreements.
Attention deficit hyperactivity disorder. Users typically benefit from reduced distractions, manageable content chunks, the ability to pause animations or auto-play media, and clear focus states that help maintain attention on the current task.
Short written description of an image, announced by screen readers in place of the image. Required for informative images under WCAG 1.1.1; purely decorative images take empty alt (alt="").
Ontario's accessibility law, in force since 2005, with phased compliance requirements for public, private and non-profit organisations. Its Information and Communications Standard explicitly references WCAG 2.0 Level AA.
A language disorder typically caused by stroke or brain injury, affecting the ability to produce or understand speech, reading or writing. Plain-language content, consistent navigation and supplementary symbols all reduce barriers for people with aphasia.
Accessible Rich Internet Applications. W3C specification of attributes that expose accessible semantics to assistive technology where native HTML cannot. The first rule of ARIA is: do not use ARIA if a semantic HTML element will do.
The three categories of WAI-ARIA attributes. Roles describe what an element is (e.g. role="button"), states describe its current condition (aria-expanded), and properties describe its relationships (aria-labelledby). Used to fill semantic gaps where native HTML cannot.
ARIA attribute pointing to another element that provides supplementary description for the current element, such as a form field's help text or error message. Read by screen readers after the element's accessible name.
ARIA attribute that supplies an accessible name for an element when visible text is missing or insufficient, such as an icon-only button. Overrides visible text for screen readers, so use carefully when text is also present.
W3C guidelines for content management systems and authoring tools, in two parts: the tool itself is accessible to authors with disabilities, and the tool helps authors produce accessible content by default.
Reduced or absent ability to hear. Includes Deaf users (no functional hearing) and hard-of-hearing users (reduced hearing). Requires captions, transcripts, sign-language interpretation where appropriate, and visual alternatives to audio cues.
A user on the autism spectrum. Typically benefits from predictable layouts, consistent navigation, literal language, and reduced sensory overload from animation, sound, busy backgrounds or unexpected interactions.
Software-based scanning for accessibility issues using tools such as axe, WAVE, Lighthouse and Pa11y. Catches roughly 30-40 percent of WCAG failures; the remainder require manual review and assistive-technology testing.
A person with little to no functional vision. Typically uses a screen reader to navigate digital content via keyboard, relying entirely on semantic structure: headings, landmarks, accessible names and alt text.
Hardware device with pins that rise and fall to render text in refreshable braille, paired with a screen reader. Used by deaf-blind users and many blind users who prefer tactile reading or work in quiet environments.
Synchronised text alternatives for audio in video, including dialogue and relevant non-speech audio. Required for pre-recorded video with audio at WCAG 1.2.2 (Level A) and for live audio at WCAG 1.2.4 (Level AA).
ExceedAbility's framing for why retrofit accessibility is harder than baked-in accessibility: you cannot remove the eggs from a chocolate cake once it has been baked. Used to justify shift-left investment in design and development rather than late-stage remediation.
Differences in how a person processes information, including memory, attention, language and executive function. Users benefit from plain language, predictable layouts, generous time limits and the ability to pause animations.
Inability or reduced ability to distinguish certain colours, most commonly red-green. Affects roughly 8 percent of men and 0.5 percent of women. Information must never depend on colour alone (WCAG 1.4.1).
The measurable ratio of luminance between foreground and background. WCAG 2.2 AA requires 4.5:1 for normal text and 3:1 for large text and UI components. Common failure point in brand-driven design systems.
Meeting all WCAG success criteria at the chosen level. Conformance applies to a complete web page, not a fragment, and to a defined scope of pages or screens within a product.
WCAG's three levels of strictness. Level A is the floor (no critical barriers). Level AA is the de facto standard required by most legislation including the Australian Digital Service Standard. Level AAA is aspirational; not all content can practically meet it.
Australian Commonwealth law making it unlawful to discriminate against a person on the basis of disability. Inaccessible digital services can lead to formal complaints to the Australian Human Rights Commission.
A person who cannot access audio at all. Needs accurate synchronised captions, transcripts, sign-language interpretation where appropriate, and visual equivalents for any audio cue or alert.
An image that conveys no information beyond visual styling, such as a corner flourish or divider. Should have an empty alt attribute (alt="") so screen readers skip it. Omitting the alt attribute entirely is wrong; many screen readers will then read the filename aloud.
Australian Government framework requiring digital services to meet accessibility, design and operational quality criteria. Accessibility is required at WCAG 2.2 Level AA for new services from 1 January 2025 and existing services from 1 January 2026.
The interaction between a person's impairment and barriers in their environment. The W3C identifies five primary functional disability groups affecting digital accessibility: visual, auditory, cognitive, physical and speech.
A genetic condition causing intellectual disability and characteristic physical features. Accessibility needs are primarily cognitive and often visual: plain language, predictable interfaces, larger text and high contrast.
Leading commercial speech-recognition product on Windows, used by people with motor disabilities, RSI or vision impairment to dictate text and control the computer by voice. Sites failing WCAG 2.1.1 (keyboard) typically also fail Dragon.
Australian Commonwealth body responsible for digital service standards across government, including accessibility reporting through the Investment Oversight Framework and the Digital Service Standard.
A user with dyslexia, a specific learning difference affecting reading. Benefits from readable typefaces, generous line and letter spacing, plain language, optional text-to-speech, tolerant search, and forms that forgive misspellings.
European Union standard for ICT accessibility, mandatory for public-sector digital services across EU member states. Builds on WCAG 2.1 and adds requirements for hardware, software and documentation.
UK statute consolidating earlier anti-discrimination law, including disability. Imposes a duty on service providers (including digital services) to make reasonable adjustments so disabled people are not put at a substantial disadvantage.
Telling the user clearly that an error has occurred and which field caused it. Covered by WCAG 3.3.1 (Level A). Best practice combines text (not colour alone), an icon, and association with the field via aria-describedby.
EU directive (in force from June 2025) requiring private-sector products and services to be accessible, including banking, e-commerce, ebooks, transport and consumer electronics. Increasingly influencing global product accessibility design.
Assistive input method that uses eye position to control a cursor and trigger selections. Used by people with severe motor impairments such as ALS. Requires generous target sizes and dwell-based activation patterns.
The sequence in which keyboard focus moves through interactive elements as the user presses Tab. Must follow a logical, predictable order matching visual reading order (WCAG 2.4.3).
A pattern that keeps keyboard focus inside a modal or dialog until it is dismissed, then returns focus to the originating element. Essential for accessible modals; without it, keyboard and screen-reader users get stranded behind the dialog.
Visible outline or change in appearance showing which element currently has keyboard focus. Required for all interactive elements (WCAG 2.4.7). Removing default focus styles without replacement is a critical accessibility failure.
Visible text associated with a form control via the label for attribute or by wrapping the input. WebAIM's annual analysis routinely finds missing form labels on roughly half of all home pages, making them one of the most common WCAG failures.
A user with reduced but not absent hearing. Benefits from adjustable audio levels, separate dialogue and background tracks, accurate captions, low background noise, and clear well-paced speech in spoken content.
A camera-based input device that translates head movement into pointer movement on screen, used by people with limited or no hand function. Examples include the Quha Zono and the built-in head tracking in macOS and iOS.
Hierarchical use of HTML headings (h1 through h6) to convey document outline. Screen reader users navigate by heading; broken hierarchy or skipped levels makes content harder to scan and orient within.
An expert-led review of a product against a checklist of accessibility heuristics, without testing every page. Faster and cheaper than a full WCAG audit; useful for early-stage triage but not a substitute for conformance testing.
Text rendered as a graphic rather than as real text, such as a JPG of a heading or quote. Fails WCAG 1.4.5 except for logos and essential cases, because users cannot resize, restyle or extract it with assistive technology.
Design philosophy treating disability and difference as central rather than as edge cases. Produces solutions for the widest range of users, and incidentally better outcomes for everyone (the curb-cut effect).
Australian Government framework requiring agencies to report on digital service accessibility. Non-compliance can trigger investment-board attention and procurement consequences for suppliers delivering inaccessible work.
Job Access With Speech. The most widely used commercial screen reader on Windows, made by Freedom Scientific. A reference target for screen reader testing alongside NVDA and VoiceOver.
Every interactive element must be reachable and operable using a keyboard alone, with no traps and a visible focus indicator (WCAG 2.1.1, 2.1.2, 2.4.7). Foundational for keyboard, switch and voice-control users.
HTML5 sectioning elements (header, nav, main, aside, footer) and equivalent ARIA roles that allow screen reader users to jump between major page regions. Should appear once per page (except navigation) and be labelled when repeated.
ARIA mechanism (aria-live, role="status", role="alert") that notifies screen reader users of content changes without moving focus. Used for form validation, toast messages, search results updating and notifications.
A person with visual impairment that cannot be corrected to normal vision. Uses zoom up to 400 percent, magnification or high-contrast modes; needs layouts that reflow without horizontal scrolling at small viewports.
The 2000 Australian Human Rights and Equal Opportunity Commission case in which the Sydney Olympics ticketing website was found to unlawfully discriminate against a blind user. Remains the standard reference cited when explaining DDA 1992 application to digital services.
Human review of digital content against accessibility criteria, including keyboard-only navigation, screen reader testing and visual inspection. Catches WCAG failures that automated tools cannot detect, particularly around meaning, context and assistive-technology support.
W3C framework for assessing organisational accessibility capability across communications, knowledge, support, policy and procurement dimensions. ExceedAbility uses this model to scope uplift programmes and to track organisational progress over time.
A dialog that blocks interaction with the rest of the page until dismissed. Accessible modals need a focus trap, an accessible name, dismissal via the Escape key, and the underlying page made inert via aria-hidden or the inert attribute on background content.
A user with reduced control of movement, including tremor, paralysis, weakness or chronic pain. May interact via keyboard, switch, voice control or eye tracking, and needs large well-spaced targets and forgiving inputs.
Microsoft's built-in screen reader for Windows. Free and ships with the operating system. Less feature-rich than JAWS or NVDA but useful for quick accessibility checks without installing additional software.
NonVisual Desktop Access. Free, open-source screen reader for Windows produced by NV Access (Australian-founded). Used by approximately half of Windows screen reader users globally and a primary testing target for web accessibility.
PDF Universal Accessibility (ISO 14289-1). The accessibility standard for PDF documents, requiring tagged content, defined reading order, language metadata, accessible forms and proper structure for assistive technologies.
Seizures triggered by flashing or rapidly changing visual content. WCAG 2.3.1 prohibits content that flashes more than three times per second above defined luminance and red-flash thresholds.
Writing designed to be understood at first reading by the intended audience. WCAG 3.1.5 (Level AAA) recommends plain language. Australian Government style guidance targets a Year-9 reading level for general public content.
The four foundational WCAG principles. Every success criterion sits under one of these four headings, making POUR the navigation backbone of WCAG itself.
The sequence in which content is read by assistive technology, determined by the DOM order. Must match visual reading order; CSS positioning that visually reorders content but not the DOM creates a mismatch and an accessibility failure.
WCAG 1.4.10 requirement that content must reflow into a single column at 320 CSS pixels wide without loss of information or horizontal scrolling. Effectively mandates responsive design at the mobile breakpoint.
Output mode of a braille display in which mechanical pins rise and fall to represent the current line of text. Updates in real time as the screen reader cursor moves through content.
Re-testing a product after changes to confirm that previously-fixed accessibility issues have not returned and new issues have not been introduced. Increasingly automated via tools such as axe-core integrated into CI/CD pipelines.
Fixing accessibility issues identified by an audit. May apply to websites, applications, documents (PDF, Word, PowerPoint) or multimedia. ExceedAbility document remediation includes tagged source files and PDF/UA-compliant outputs.
Software that enlarges part of the screen for low-vision users. Examples include ZoomText, Windows Magnifier and macOS Zoom. Effective only when layouts reflow at the magnification level rather than triggering horizontal scroll.
Software that converts on-screen content into synthesised speech or refreshable braille. Used primarily by blind and many low-vision users. Major examples: JAWS and NVDA on Windows, VoiceOver on macOS and iOS, TalkBack on Android, Narrator on Windows.
United States federal law requiring electronic information technology used by federal agencies to be accessible. Currently aligned with WCAG 2.0 Level AA via the Section 508 Refresh and increasingly invoked in procurement worldwide.
Use of HTML elements according to their meaning (button for buttons, nav for navigation, h2 for headings) rather than styled divs. Provides accessibility for free via the browser's accessibility tree and is the foundation that ARIA builds on.
A classification applied to each audit finding, typically Critical, High, Medium or Low, reflecting the impact on users and the legal or business risk. ExceedAbility reports include severity ratings on every finding to support remediation prioritisation.
Moving accessibility activity earlier in the delivery lifecycle: requirements, design, code review, automated CI checks rather than only end-of-cycle audit. Reduces total cost because issues found in design cost a fraction of issues found in production.
A switch input controlled by sipping or puffing on a tube, typically mounted near the mouth. Used by people with high-level spinal injuries, ALS or other conditions affecting limb function. Categorised as a switch device under WCAG.
A temporary mismatch between a person and their environment that affects access, such as using a phone in bright sunlight, holding a baby one-handed, or watching a video in a quiet office. Accessible design benefits everyone in these moments, which is why accessibility equals good UX.
Hidden link at the top of a page that becomes visible on keyboard focus, jumping past repeated navigation to the main content. Required by WCAG 2.4.1 Bypass Blocks and a fast win on most legacy sites.
ExceedAbility's framework positioning accessibility as the essential third pillar of digital compliance alongside security and privacy. Security and privacy mean nothing to a user who cannot access them.
A user with difficulty producing intelligible speech, ranging from articulation differences to non-speaking. Needs text-based alternatives to voice interfaces, IVR menus and speech authentication, plus support for augmentative communication devices.
A specific, testable WCAG rule. WCAG 2.2 contains 87 success criteria across Level A, AA and AAA, organised under the four POUR principles. Each criterion has techniques showing how to meet it and failures showing how it commonly breaks.
WCAG techniques documented by the W3C that, if implemented correctly, are sufficient to meet a success criterion. Distinguished from advisory techniques (helpful but not required) and failures (known ways to violate a criterion).
Single-button or multi-button input device used by people with severe motor impairments. Combined with scanning interfaces in the operating system or assistive software to operate computers without a keyboard or mouse.
Google's built-in screen reader for Android. Free and ships with the operating system. Used by blind and low-vision users to operate phones and tablets via touch gestures and synthesised speech.
The interactive area of a control such as a button or link. WCAG 2.5.8 (Level AA, new in 2.2) requires touch targets of at least 24 by 24 CSS pixels with adequate spacing; WCAG 2.5.5 (Level AAA) prefers 44 by 44.
A disability lasting weeks or months rather than permanently, such as a broken arm, post-surgical recovery, concussion or ear infection. Roughly one in four adults experiences a temporary disability in any given year; accessible design supports them too.
Software that converts written text into synthesised speech. The technology underlying all screen readers, but also used standalone for reading support, language learning and accessibility built into operating systems such as macOS Speak Selection and Read Aloud in Edge.
The process of reviewing audit findings and deciding what to fix, in what order, on what timeline. Effective triage combines severity, user impact, fix cost and strategic context; without it, large audit reports tend to stall remediation rather than enable it.
Watching real users with disabilities complete tasks using their assistive technology of choice. Catches usability barriers that conformance testing misses entirely and is central to inclusive product design.
A user with an inner-ear condition causing motion sensitivity. Affected by parallax effects, large slide transitions and auto-scrolling. WCAG 2.3.3 (Level AAA) and the prefers-reduced-motion media query address these patterns.
Software that allows hands-free operation of a device by speech, such as Dragon NaturallySpeaking, macOS Voice Control and Windows Voice Access. Used by people with motor disabilities and increasingly by general users for convenience.
Apple's built-in screen reader on macOS, iOS and iPadOS. Operated via gestures on touch devices and keyboard or trackpad shortcuts on Mac. The reference target for testing accessibility on Apple platforms.
A widely-used form of Accessibility Conformance Report originating in the US, documenting how a product conforms to WCAG, Section 508 or EN 301 549. Required in many US, EU and Australian government procurements.
Web Accessibility Initiative - Accessible Rich Internet Applications. The full name of the ARIA specification published by the W3C Web Accessibility Initiative.
The W3C standard for digital accessibility, used worldwide as the basis for accessibility law and policy. Organised around four principles (POUR) and three conformance levels (A, AA, AAA).
The first widely-adopted version of WCAG, published in December 2008 as an ISO standard. Still referenced in some Australian state and federal procurement contracts and forms the basis of WCAG 2.1 and 2.2, which are backward-compatible supersets.
Published June 2018. Added 17 success criteria over WCAG 2.0, focused on mobile accessibility, low vision and cognitive disabilities. Still the default reference in many Australian government contracts that predate the 2025 WCAG 2.2 transition.
Current published version of WCAG (October 2023). Adds nine new success criteria over WCAG 2.1, focused mainly on motor disabilities and cognitive accessibility. Required for new Australian government services from 1 January 2025.
Successor standard in active development, sometimes called Silver. Introduces a new outcome-based scoring model and broader scope covering apps, hardware, AR/VR and AI. Still a working draft in 2026; WCAG 2.2 remains the operative standard.
EU Directive 2016/2102 requiring public sector websites and mobile apps in member states to meet EN 301 549, which references WCAG 2.1 Level AA. Each member state implements it in domestic law; enforcement is via designated national bodies.
Screen magnification and reading software for Windows, made by Freedom Scientific. Combines magnification, contrast enhancement and text-to-speech for low-vision users in a single product.
Plain answers to the questions buyers, designers, developers and content authors ask most often.
Digital accessibility is the practice of designing and building websites, applications and documents so that people with disabilities can use them. It addresses barriers across five functional disability groups (visual, auditory, cognitive, physical and speech) and is most often measured against the W3C Web Content Accessibility Guidelines (WCAG).
WCAG 2.2 (October 2023) adds nine new success criteria to WCAG 2.1, focused mainly on motor disabilities and cognitive accessibility. Notable additions at Level AA include 2.4.11 Focus Not Obscured, 2.5.7 Dragging Movements, 2.5.8 Target Size (Minimum) and 3.3.7 Redundant Entry. WCAG 2.2 is required for new Australian government digital services from 1 January 2025.
Level AA is the de facto standard required by most accessibility legislation, including the Australian Digital Service Standard, the EU Web Accessibility Directive and Section 508. Level A is the floor (no critical barriers) and Level AAA is aspirational; not all content can practically meet AAA. Most engagements target Level AA across all in-scope pages.
An accessibility audit is the assessment process: testing against WCAG and producing findings with severity ratings and remediation guidance. A VPAT (Voluntary Product Accessibility Template) is one format of Accessibility Conformance Report, a public-facing summary of how a product conforms to WCAG, Section 508 or EN 301 549. An audit typically informs a VPAT but is much more detailed.
Test with the screen readers your users actually use. For most public-facing Australian services that means NVDA and JAWS on Windows, VoiceOver on macOS and iOS, and TalkBack on Android. WebAIM's annual Screen Reader User Survey reports JAWS, NVDA and VoiceOver collectively cover roughly 95 percent of screen reader users globally.
Accessible PDFs require: proper document tags (headings, lists, paragraphs, tables), defined reading order, alt text on informative images, accessible form fields, language metadata, and a document title set in document properties. PDF/UA (ISO 14289-1) is the formal standard. ExceedAbility's document remediation service delivers tagged source files and PDF/UA-compliant outputs.
Contact our team to scope an audit, document remediation pass, or capability uplift programme. A 20-minute Discovery Call is usually enough to scope the work.
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