People & access
Accessibility
Designing content, tools, and services so people with disabilities can use them.
- In practice
- A person can complete a form using a keyboard, understand its instructions, and correct errors.
Resources / Accessibility glossary
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86 terms
Choose a letter to jump to its terms. Muted letters have no entries. Search and topic filters narrow the sections below.
Testing & improvements
Accessibility audit
A structured evaluation of accessibility within a defined scope, often against specified standards.
- In practice
- A report explains which pages and tasks were tested, the methods used, and the barriers found. An audit is not automatically a certification.
People & access
Accessibility barrier
Something that makes a task difficult or impossible for a person with a disability.
- In practice
- An unlabeled form field can leave someone unsure what information to enter.
Testing & improvements
Accessibility statement
A public explanation of an organization’s accessibility work, known limitations, and ways to report problems.
- In practice
- A statement names the content covered and gives a usable contact method for accessibility feedback.
Web & interaction
Accessible name
The name that assistive technology uses to identify a control or other element.
- In practice
- A search button needs a name that communicates its purpose, even if its visible content is only a magnifying-glass icon.
Web & interaction
Accordion
A set of sections whose content can be expanded or collapsed through heading controls.
- In practice
- An FAQ lets you open an answer using a button that communicates whether its section is expanded.
Standards & reporting
ACR (Accessibility Conformance Report)
A report describing how a product meets specified accessibility requirements, commonly prepared using a VPAT.
- In practice
- Review the product version, evaluation methods, explanations, and known limitations when comparing products. The report is evidence to assess, not a blanket guarantee.
Organizations & credentials
ADS (Accessible Document Specialist)
An IAAP technical certification recognizing skills and experience in accessible electronic documents.
- In practice
- Relevant work includes creating, evaluating, and remediating formats such as PDF and EPUB. Holding ADS does not automatically certify an individual document.
Content & documents
Alt text (alternative text)
A text alternative that communicates an image’s relevant meaning or function in its context.
- In practice
- A linked logo may need text identifying its destination. A chart may also need a detailed explanation or data table. Decorative images generally use an empty text alternative.
People & access
Alternative input
A way of operating technology other than a conventional mouse or keyboard setup.
- In practice
- Someone may use switches, speech input, or an eye-tracking system to interact with a website.
People & access
Assistive technology
Hardware or software that people with disabilities use to perform tasks or access information.
- In practice
- Screen readers, screen magnifiers, and alternative input devices are examples. People use different tools and settings.
Content & documents
Audio description
Description of important visual information in a video that is not conveyed through its existing audio.
- In practice
- A narrator explains an on-screen action during a pause in dialogue so someone who cannot see it can follow the story.
Testing & improvements
Automated testing
Using software to identify accessibility issues that can be checked automatically.
- In practice
- A checker can flag some missing text alternatives, but a person must evaluate whether an alternative communicates the right information. A clean scan does not prove accessibility.
Tools & assistive software
axe DevTools
Deque’s accessibility testing tools, including a browser extension for finding automatically detectable website issues.
- In practice
- The extension has free automated checks and additional paid features. Use findings alongside manual evaluation; a clean automated scan does not establish accessibility.
People & access
Braille display
A device with changing raised dots that presents digital text in braille.
- In practice
- A refreshable braille display can work with screen-reader software to make page text available by touch.
Web & interaction
Breadcrumb navigation
A trail of links showing where a page sits within a site’s hierarchy.
- In practice
- Home, Resources, and Glossary can show a path back to broader sections.
Content & documents
Captions
Synchronized text conveying speech and meaningful non-speech audio in media.
- In practice
- Captions identify an off-screen speaker and a ringing alarm when that information matters. Automatic captions need review for accuracy.
People & access
Cognitive accessibility
Design that supports people with differences in memory, attention, understanding, learning, or problem-solving.
- In practice
- Clear instructions and predictable steps can help someone complete a task without having to remember information from another page.
Web & interaction
Color contrast
The difference in lightness between colors, such as text and its background, that affects how easily content can be distinguished.
- In practice
- Pale gray text on white may be difficult to read. Check the relevant contrast requirements instead of judging by appearance alone.
Tools & assistive software
Colour Contrast Analyser (CCA)
A desktop tool associated with TPGi, now presented by Vispero, for checking foreground and background color contrast.
- In practice
- Use its color picker to sample an interface or document. It checks selected color pairs, not the accessibility of the whole design.
Standards & reporting
Conformance
Meeting the requirements of a specified standard at a stated level and within a defined scope.
- In practice
- A WCAG evaluation identifies the version, level, and content covered. Meeting a technical standard is different from determining compliance with a law.
Organizations & credentials
CPABE (Certified Professional in Accessible Built Environments)
A former IAAP credential focused on accessibility in physical spaces. IAAP stopped offering it in mid-2024.
- In practice
- You may encounter CPABE on an older professional profile. IAAP permits holders to display it through their credential’s expiration date.
Organizations & credentials
CPACC (Certified Professional in Accessibility Core Competencies)
IAAP’s foundational certification covering disability, accessibility and universal design, and accessibility-related standards and management.
- In practice
- CPACC demonstrates broad accessibility knowledge across roles; it is not a technical audit of a website.
Organizations & credentials
CPWA (Certified Professional in Web Accessibility)
An IAAP credential awarded to people who earn both CPACC and WAS while the first credential is still valid.
- In practice
- It combines foundational accessibility knowledge with technical web accessibility expertise, without a separate CPWA exam.
Content & documents
Decorative image
An image that adds visual styling without information needed to understand or operate the content.
- In practice
- A purely decorative flourish in HTML generally uses an empty alt attribute so it is not announced as useful content.
Content & documents
Descriptive link text
Link wording that helps people understand the destination or purpose.
- In practice
- “Download the event schedule (PDF)” provides more information than “Click here.”
Web & interaction
Dialog box
A separate window or panel used for a task or message within an interface. Also called a dialog.
- In practice
- A modal dialog box requires attention before returning to the page; keyboard focus needs to enter it, remain within it while open, and return appropriately when it closes.
People & access
Environmental barriers
Features of someone’s surroundings that restrict access or make a task difficult. They can contribute to situational limitations for people with or without a disability.
- In practice
- Bright sunlight can make a low-contrast screen hard to read; background noise can make audio hard to hear. These are barriers created by the environment.
People & access
Episodic disability
A disability whose effects recur or fluctuate, so someone’s access needs may vary at different times.
- In practice
- A person may experience periods of fatigue or pain and need different input methods, flexible timing, or more breaks on some days.
Web & interaction
Error identification
Clearly telling someone which input has a problem and what the problem is.
- In practice
- “Enter an email address in name@example.com format” gives more direction than a red outline alone.
Web & interaction
Focus indicator
A visible sign showing which element is currently receiving keyboard input.
- In practice
- A clear outline around a link helps a keyboard user know what will activate when they press Enter.
Web & interaction
Focus order
The sequence in which controls receive keyboard focus.
- In practice
- Tab should move through a form in an order that preserves meaning and lets someone operate it.
Web & interaction
Form label
Text identifying what a form control is for, with an appropriate programmatic connection to that control.
- In practice
- An email field has a visible “Email address” label that is also available to a screen reader.
Content & documents
Heading structure
Headings marked with their actual structural roles and organized to show how sections relate.
- In practice
- Use Heading 1 for a document’s main heading and Heading 2 for its main sections, rather than only making ordinary text larger and bold.
Organizations & credentials
IAAP (International Association of Accessibility Professionals)
A global professional association supporting accessibility through education, community, and professional certification.
- In practice
- IAAP awards credentials such as CPACC, WAS, and ADS. Membership alone does not mean someone holds a certification.
Content & documents
Image of text
Words presented as part of an image rather than as actual text.
- In practice
- A flyer containing an event date needs an accessible text equivalent. Actual text is generally easier to resize and customize.
Tools & assistive software
JAWS (Job Access With Speech)
A screen reader for Windows from Freedom Scientific, part of Vispero, that provides speech and braille access to digital content.
- In practice
- A person can navigate documents and websites with JAWS keyboard commands. Output can vary with browser, settings, and content structure.
Web & interaction
Keyboard accessibility
Being able to operate functionality through a keyboard interface without requiring specific timing for individual keystrokes.
- In practice
- Someone can open a menu, choose an item, and close the menu without using a mouse. Arrow keys and other keys may be needed as well as Tab.
Web & interaction
Keyboard trap
A situation where keyboard focus enters a component but cannot leave it using the expected keyboard methods.
- In practice
- Someone can enter a calendar widget but cannot move back to the rest of the form. A properly managed modal with a working exit is different.
Web & interaction
Landmark
A programmatically identified page region that can help people navigate between major areas.
- In practice
- Navigation and main content regions let screen-reader users move directly to useful sections.
Web & interaction
Live region
A marked area that allows assistive technology to announce content changes without moving focus there.
- In practice
- A polite status update announces how many glossary terms match a search. Avoid announcing every change unnecessarily.
People & access
Low vision
A range of vision impairments that can affect activities such as reading or recognizing detail, even with correction.
- In practice
- A person may enlarge text, change colors, or use screen magnification; preferences and needs vary.
Testing & improvements
Manual testing
Accessibility checks that require a person’s judgment or interaction.
- In practice
- A tester follows a checkout process with a keyboard and evaluates whether errors are understandable and focus moves appropriately.
Tools & assistive software
NVDA (NonVisual Desktop Access)
A free, open-source screen reader for Microsoft Windows, developed by NV Access.
- In practice
- People use NVDA to read and operate digital content. Testers can use it to investigate barriers, while recognizing that one tester’s experience does not represent every user.
Content & documents
OCR (optical character recognition)
Software recognition of printed or scanned characters to produce machine-readable text.
- In practice
- OCR can make a scanned page searchable, but its accuracy and document structure still need checking. It does not make a PDF fully accessible by itself.
Standards & reporting
Operable
The accessibility principle that people must be able to operate interface controls and navigation.
- In practice
- Provide keyboard operation and enough time to complete a task.
Tools & assistive software
PAC (PDF Accessibility Checker)
A tool for checking many PDF accessibility requirements and reviewing a document’s structure.
- In practice
- Use PAC after remediation to find potential issues and inspect structure previews. Automated results still need the required human checks.
Standards & reporting
Perceivable
The accessibility principle that information must be available in ways people can perceive.
- In practice
- Provide captions for meaningful audio and text alternatives for relevant images.
People & access
Permanent disability
A disability that is lasting or ongoing. A person’s access needs can still change over time or across situations.
- In practice
- Someone with a lasting limb difference may use alternative input methods. Designing for that need can also help someone with a temporary injury.
Content & documents
Plain language
Writing organized and worded so its intended audience can find, understand, and use the information.
- In practice
- “Send the form by Friday” is more direct than “Submission of documentation must be effectuated prior to the deadline.” Plain language still needs to preserve meaning.
Standards & reporting
POUR
A memory aid for four WCAG principles: perceivable, operable, understandable, and robust.
- In practice
- Use these principles to think about barriers, then consult specific requirements for evaluation.
Web & interaction
Programmatic relationship
A connection expressed in code so software can identify how pieces of content relate.
- In practice
- A table header is associated with its data cells rather than distinguished only by bold formatting.
Content & documents
Reading order
The sequence in which content is presented when read or navigated, including by assistive technology.
- In practice
- A two-column PDF should not jump between unrelated sentences across columns. Visual placement alone does not establish a useful reading order.
Web & interaction
Reduced motion
A user preference for reducing animations that may cause discomfort or interfere with use.
- In practice
- A site can honor a device’s reduced-motion setting by removing nonessential animated transitions.
Web & interaction
Reflow
Content adapting to a narrower viewing area so it remains readable and usable without unnecessary scrolling in two directions.
- In practice
- When a page is enlarged, text can wrap into one column instead of forcing someone to scroll sideways for every line. Some content, such as data tables, may need two-dimensional layout.
Testing & improvements
Remediation
Changing content or code to address identified accessibility barriers, then checking the result.
- In practice
- Repair document headings and reading order, then verify that the exported file retains usable structure.
Standards & reporting
Robust
The accessibility principle that content can be interpreted reliably by different user agents, including assistive technologies.
- In practice
- Use controls whose name, role, and state are available to accessibility tools.
People & access
Screen magnifier
Software that enlarges part or all of the screen.
- In practice
- Someone may view only a small portion of a page at a time, making clear layout and predictable placement useful.
People & access
Screen reader
Software that presents information from digital interfaces through synthesized speech or a refreshable braille display.
- In practice
- A reader can move through a page by its headings or links. Useful output depends on the content’s structure and labeling, not just how it looks.
Web & interaction
Semantic HTML
HTML elements used for their intended meaning and role.
- In practice
- Use a button element for an action and a heading element for a section heading. Their appearance can still be styled.
People & access
Situational limitation (situational disability)
A restriction on someone’s ability to use content or technology caused by their immediate circumstances. Inclusive design also uses the term situational disability.
- In practice
- Someone holding a baby has one hand available. Captions can help someone who cannot hear a video in a noisy setting.
Web & interaction
Skip link
A link that lets someone bypass repeated content and move to a main section.
- In practice
- “Skip to main content” avoids tabbing through the same menu on every page.
People & access
Speech recognition
Technology that converts speech into text or commands.
- In practice
- A person says a button’s visible label to activate it; matching visible and programmatic names helps this work.
Web & interaction
Status message
Information about an action’s result, progress, or state that does not itself move focus.
- In practice
- “Your changes were saved” should be available to assistive technology when appropriate, not only shown visually.
Standards & reporting
Success criterion
A testable statement used to assess conformance in WCAG 2.
- In practice
- A criterion may address keyboard operation or captions. Its level and version matter when evaluating content.
Content & documents
Table headers
Cells identified as headings for rows or columns in a data table.
- In practice
- A screen reader can announce “Tuesday” and “Opening time” when someone navigates a schedule’s data cells.
Content & documents
Tagged PDF
A PDF with a structure tree identifying elements such as headings, paragraphs, lists, and tables.
- In practice
- Tags help communicate structure and reading order, but the presence of tags alone does not prove they are correct.
Tools & assistive software
TalkBack
Google’s screen reader for Android devices, providing spoken feedback and navigation support.
- In practice
- Someone explores a phone interface using TalkBack gestures. Testing on mobile helps reveal issues that desktop checks may not expose.
Web & interaction
Target size
The dimensions of an interactive area that responds to a pointer or touch.
- In practice
- A small icon may be difficult to activate. Adequate size and spacing help reduce accidental selections.
People & access
Temporary disability
A disability or impairment experienced for a limited period, such as during recovery from an injury or surgery.
- In practice
- A person with a broken arm may need keyboard access or speech input while they cannot comfortably use a mouse.
Content & documents
Text spacing
The space between letters, words, lines, and paragraphs.
- In practice
- Someone increases line spacing to read more comfortably; text and controls should remain usable rather than overlap or disappear.
Content & documents
Transcript
A text version of speech and meaningful audio information; a descriptive transcript also includes important visual information.
- In practice
- Someone can read an interview instead of listening. A video transcript may also describe actions or on-screen text needed to understand it.
Standards & reporting
Understandable
The accessibility principle that information and interface operation must be understandable.
- In practice
- Use clear instructions and explain how someone can correct an input error.
Testing & improvements
Usability testing
Observing people attempting representative tasks to learn what works and where they encounter difficulty.
- In practice
- Invite participants with disabilities to try registering for an event. Their experience complements standards-based checks; neither replaces the other.
Tools & assistive software
VoiceOver
Apple’s built-in screen reader, available across supported Apple devices.
- In practice
- Someone may use gestures on an iPhone or keyboard commands on a Mac to explore and operate content. Interaction differs by device.
Standards & reporting
VPAT (Voluntary Product Accessibility Template)
An Information Technology Industry Council template for documenting how an information or communications technology product meets accessibility standards.
- In practice
- A completed VPAT becomes an Accessibility Conformance Report (ACR). A blank template or completed report is not a product certification.
Standards & reporting
W3C (World Wide Web Consortium)
An international nonprofit organization where members, staff, and the public work together to develop open web standards. Its accessibility work includes WCAG and WAI-ARIA.
- In practice
- When you follow WCAG guidance to improve a website, you are using guidelines developed through W3C’s collaborative standards process.
Organizations & credentials
WAI (Web Accessibility Initiative)
W3C’s initiative coordinating work on accessibility standards, guidance, education, and resources.
- In practice
- The WAI website offers tutorials and explanations that help people understand and apply accessibility guidance.
Standards & reporting
WAI-ARIA (ARIA)
A technical specification for communicating roles, states, and properties to accessibility tools, especially for interactive interfaces.
- In practice
- A custom disclosure can communicate whether it is expanded. ARIA does not add keyboard behavior or automatically fix an inaccessible control.
Organizations & credentials
WAS (Web Accessibility Specialist)
An IAAP technical certification for professionals with experience developing, testing, and evaluating web accessibility.
- In practice
- A web professional may earn WAS to demonstrate technical knowledge and experience. The credential belongs to the person, not to every website they work on.
Tools & assistive software
WAVE
WebAIM’s suite of web accessibility evaluation tools that presents findings within the context of a page.
- In practice
- WAVE highlights errors, alerts, and accessibility features. Human review is still needed to understand the findings and discover issues automation misses.
Standards & reporting
WCAG
Web Content Accessibility Guidelines: W3C recommendations for making web content more accessible to people with disabilities.
- In practice
- WCAG 2 uses success criteria at levels A, AA, and AAA. An evaluation should state the version and level being assessed.
Standards & reporting
WCAG 3 draft
An unfinished next-generation accessibility guideline being developed by W3C. Its requirements and reporting approach may change.
- In practice
- Discussion of a draft proposal does not mean that proposal is a current requirement or that WCAG 2 has been replaced.
Organizations & credentials
WebAIM (Web Accessibility In Mind)
An accessibility organization based at Utah State University that provides training, guidance, evaluation services, and tools.
- In practice
- WebAIM publishes accessibility articles and provides WAVE and the WebAIM Contrast Checker.
Tools & assistive software
WebAIM Contrast Checker
A browser-based tool that calculates the contrast ratio between foreground and background colors and reports WCAG contrast results.
- In practice
- Enter text and background colors, then review the results for the relevant text size and level. Also check other content and interaction states.
Web & interaction
Zoom
Enlarging or reducing the displayed size of content in a browser or another application.
- In practice
- At increased browser zoom, check that information remains available and controls remain usable as the layout changes.
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