Website ADA Compliance Definitions

If you’ve started researching website accessibility or ADA compliance, you’ve probably noticed there are a lot of unfamiliar terms used in the industry. Between legal language, technical standards, and web development concepts, it can sometimes feel like learning a completely new vocabulary.

This page is meant to help simplify things.

Below you’ll find a glossary of common accessibility terms used when discussing ADA compliance, WCAG standards, and website accessibility. Whether you’re new to the topic or just looking for a quick reference, these definitions are meant to make the language of accessibility easier to understand.

Core Accessibility Laws and Standards

ADA Compliance

ADA compliance refers to meeting accessibility requirements under the Americans with Disabilities Act (ADA), a civil rights law passed in 1990 that prohibits discrimination against individuals with disabilities. The law applies to a wide range of public services, including businesses that serve the public.

While the ADA itself does not specifically outline technical requirements for websites, courts and regulatory agencies have increasingly interpreted the law to include digital accessibility. As a result, many businesses work to meet WCAG accessibility standards, which have become the widely accepted benchmark for evaluating website accessibility.

Organizations that fail to make their websites accessible may face legal complaints, accessibility demand letters, or lawsuits alleging that their digital services prevent equal access for individuals with disabilities.

Learn more about the ADA here: https://www.ada.gov

Section 508 Compliance

Section 508 compliance refers to requirements established by Section 508 of the Rehabilitation Act, which was amended in 1998 to address accessibility in electronic and information technology used by the federal government. Under Section 508, federal agencies must ensure that their websites, digital documents, software, and other electronic content are accessible to individuals with disabilities.

For websites, Section 508 standards generally align with WCAG accessibility guidelines, particularly WCAG Level AA conformance. While Section 508 primarily applies to federal agencies, it may also apply to private organizations that receive federal funding or provide services under federal contracts.

In practice, this means that organizations working with government agencies are often required to ensure that their digital platforms meet accessibility standards similar to those required for ADA compliance.

Learn more about Section 508: https://www.section508.gov

WCAG (Web Content Accessibility Guidelines)

The Web Content Accessibility Guidelines (WCAG) are internationally recognized standards created to help make web content accessible to people with disabilities. These guidelines are developed by the World Wide Web Consortium (W3C) through its Web Accessibility Initiative.

WCAG provides technical recommendations that help designers and developers ensure that websites can be used by individuals with visual, hearing, mobility, and cognitive disabilities. The guidelines are organized around four fundamental principles known as the POUR principles, which state that content should be perceivable, operable, understandable, and robust.

Because WCAG provides measurable accessibility standards, it has become the primary reference used by organizations and courts when evaluating whether a website meets accessibility expectations under the ADA.

Learn more: https://www.w3.org/WAI/standards-guidelines/wcag/

WCAG 2.1

WCAG 2.1 was released in June 2018 as an expansion of earlier accessibility guidelines. The update introduced additional criteria designed to improve accessibility for mobile devices, individuals with low vision, and people with certain cognitive disabilities.

Although newer standards now exist, WCAG 2.1 Level AA is still commonly referenced in accessibility policies and legal settlements. Many organizations continue to use WCAG 2.1 as their baseline accessibility target when evaluating website compliance.

Learn more: https://www.w3.org/TR/WCAG21/

WCAG 2.2

WCAG 2.2, released in October 2023, represents the most recent update to the accessibility guidelines. The update introduces new success criteria that focus on improving usability for individuals with cognitive disabilities, keyboard users, and people with low vision.

Several of the new recommendations address issues such as improved focus visibility, alternatives to dragging actions, accessible authentication processes, and minimum target sizes for interactive elements like buttons and links.

Because WCAG 2.2 builds on previous versions rather than replacing them, organizations that meet WCAG 2.2 Level AA are generally considered to meet or exceed the accessibility expectations previously associated with WCAG 2.1.

Learn more: https://www.w3.org/TR/WCAG22/

WCAG Conformance Levels (A, AA, AAA)

WCAG guidelines include three levels of conformance that represent increasing levels of accessibility.

Level A addresses the most basic accessibility barriers that could prevent users from accessing content entirely.
Level AA represents a stronger level of accessibility and is the most commonly adopted standard for organizations working toward ADA compliance.
Level AAA represents the highest level of accessibility, but can be difficult for many websites to fully implement due to design and technical constraints.

Most accessibility regulations and legal settlements reference WCAG Level AA compliance.

Learn more: https://www.w3.org/WAI/WCAG22/quickref/

Accessibility Technology and Tools

Assistive Technology

Assistive technology refers to tools and software that help individuals with disabilities interact with digital content. These technologies allow users to navigate websites, read content, and complete tasks that might otherwise be difficult or impossible.

Examples of assistive technology include screen readers, voice recognition software, screen magnification tools, alternative keyboards, and switch devices. Websites that are designed according to accessibility standards ensure that these tools can properly interpret and interact with page content.

Learn more: https://www.w3.org/WAI/fundamentals/accessibility-intro/

Screen Reader

A screen reader is a software application that converts digital text into spoken output or braille so that individuals who are blind or visually impaired can access website content.

Screen readers interpret the structure of a webpage, including headings, navigation links, form fields, and image descriptions. Popular screen readers include NVDA, JAWS, VoiceOver (built into iPhones and iOS devices), and TalkBack (Android devices). Accessible websites rely on proper HTML structure and descriptive alternative text so that screen readers can accurately communicate information to users.

Voice Navigation

Voice navigation allows users to control a computer or navigate a website using spoken commands rather than a mouse or keyboard. This technology is often used by individuals with mobility impairments or conditions that limit fine motor control.

Many modern operating systems include built-in voice control tools, and third-party software such as speech recognition programs can also assist users in interacting with digital content.

Keyboard Navigation

Keyboard navigation allows users to interact with a website using only a keyboard. Instead of clicking links with a mouse, users move through page elements using keys such as Tab, Shift + Tab, Enter, and the arrow keys.

For individuals who cannot use a mouse due to mobility impairments or assistive technology requirements, keyboard navigation is essential. Accessible websites ensure that all interactive components can be accessed and operated using a keyboard.

Learn more: https://www.w3.org/WAI/WCAG22/Understanding/keyboard.html

Accessibility Design and Development Concepts

Website Accessibility

Website accessibility refers to designing and developing websites so that people with disabilities can access and use digital content without barriers. This includes ensuring that information can be perceived, navigation can be performed using different input methods, and content can be understood by users with a wide range of abilities.

Accessible websites consider the needs of individuals with visual impairments, hearing impairments, mobility limitations, and cognitive disabilities. By following accessibility best practices, organizations create a more inclusive online experience while also improving usability for all users.

A11y

A11y is a shorthand abbreviation commonly used within the accessibility community to represent the word accessibility. The number eleven represents the eleven (11) letters between the first letter “A” and the last letter “Y” in the word.

Developers, designers, and accessibility professionals frequently use the term when discussing accessibility improvements, inclusive design practices, and accessibility testing.

Alternative Text (Alt Text)

Alternative text, commonly called alt text, is a written description added to images so that screen readers can convey the image’s meaning to users who cannot see it.

Well-written alt text provides enough context to help users understand the image’s purpose without overwhelming them with unnecessary details. In addition to supporting accessibility, alt text also helps search engines understand image content.

Learn more: https://www.w3.org/WAI/tutorials/images/

ARIA (Accessible Rich Internet Applications)

ARIA is a set of HTML attributes designed to improve accessibility for complex web applications and dynamic interface components. These attributes, added to the webpage code, provide additional information to assistive technologies about how interactive elements behave.

ARIA is commonly used to enhance components such as dropdown menus, modal windows, tab panels, and interactive widgets. However, accessibility experts recommend using native HTML elements whenever possible before relying on ARIA attributes.

Learn more: https://www.w3.org/WAI/ARIA/apg/

Accessible Forms

Accessible forms ensure that users with disabilities can successfully interact with form fields, understand instructions, and submit information without encountering barriers.

This typically involves clearly labeling form fields, providing helpful instructions, identifying errors in a way that assistive technologies can detect, and ensuring that form elements can be accessed using keyboard navigation.

Forms are one of the most common areas where accessibility issues occur on websites.

Color Contrast

Color contrast refers to the visual difference between foreground elements, such as text, and the background behind them. If contrast is too low, users with low vision or color blindness may struggle to read content.

WCAG guidelines specify minimum contrast ratios that help ensure text remains readable. For most standard body text, the required contrast ratio is 4.5:1 for Level AA compliance. For headings and other large-scale text, a 3:1 ratio is required.

Learn more: https://www.w3.org/WAI/WCAG22/Understanding/contrast-minimum.html

Focus Indicator

A focus indicator is the visual outline or highlight that appears when a user navigates through a page using a keyboard. This indicator helps users understand which element is currently selected.

Without visible focus indicators, keyboard users may have difficulty navigating through links, buttons, and form fields.

Skip Navigation Links

Skip navigation links allow users to bypass repetitive navigation menus and jump directly to the main content of a page. These links are particularly helpful for users navigating with keyboards or screen readers.

Learn more: https://www.w3.org/WAI/WCAG22/Understanding/bypass-blocks.html

Semantic HTML

Semantic HTML refers to using meaningful HTML elements to structure web content. Elements such as <header>, <nav>, <main>, <article>, and <footer> help assistive technologies understand how a webpage is organized. Proper semantic structure improves accessibility, usability, and search engine understanding of a page.

Accessibility Audits and Policies

Accessibility Audit

An accessibility audit is a systematic evaluation of a website to determine whether it meets accessibility standards such as WCAG 2.2 Level AA. Audits often include automated testing tools, manual testing by accessibility specialists, keyboard navigation testing, and screen reader testing. The results of an audit typically identify accessibility barriers and provide recommendations for remediation.

Accessibility Statement

An accessibility statement is a public document published on a website that explains the organization’s approach to accessibility. These statements often describe which accessibility standards are being followed, identify known limitations, and provide contact information for reporting accessibility concerns. Accessibility statements help organizations demonstrate transparency and commitment to improving accessibility.

WCAG Success Criteria Explained

When people talk about WCAG compliance, they are usually referring to the WCAG success criteria. These are the measurable technical requirements used to determine whether a website meets accessibility standards.

Each success criterion describes a specific accessibility requirement that websites should meet. For example, one criterion may require text to have sufficient color contrast, while another ensures that websites can be navigated using a keyboard.

The success criteria are organized under four accessibility principles that form the foundation of WCAG. These principles are often referred to as the POUR principles, which stand for:

Perceivable

The perceivable principle means that information must be presented in ways that users can perceive. In practice, this means that users should be able to see or hear the content presented on a website. Examples include providing alternative text for images, captions for videos, and sufficient color contrast between text and background elements.

Operable

Operable means that users must be able to navigate and interact with a website regardless of how they access it. This includes ensuring that all website functionality can be used with a keyboard, providing enough time for users to complete actions, and avoiding design elements that may trigger seizures or physical reactions.

Understandable

The understandable principle focuses on making website content and navigation easy to comprehend. Websites should present information clearly, maintain consistent navigation, and provide helpful instructions or error messages when users interact with forms or other features.

Robust

Robust means that website content should be compatible with a wide range of technologies, including current and future assistive technologies. Proper use of semantic HTML, accessible markup, and structured content ensures that assistive tools such as screen readers can interpret website content correctly.

Learn more about WCAG success criteria here: https://www.w3.org/WAI/WCAG22/Understanding/

Accessibility Testing Tools

Accessibility testing tools help developers and accessibility specialists identify potential barriers that may prevent individuals with disabilities from using a website. These tools can scan web pages for common accessibility issues, highlight areas that require improvement, and provide guidance on how to fix them.

While automated tools are helpful, they cannot detect every accessibility problem. For that reason, accessibility experts often combine automated testing with manual testing methods such as keyboard navigation testing and screen reader testing. Using both approaches provides a more complete picture of how accessible a website actually is.

Several widely used accessibility testing tools include the following.

WAVE Accessibility Tool

The WAVE accessibility tool analyzes web pages and highlights potential accessibility issues directly on the page. It helps developers identify problems such as missing alternative text, poor contrast, and structural markup issues. WAVE is commonly used during accessibility audits because it provides visual indicators showing where issues exist within the page.

Learn more:https://wave.webaim.org

Axe Accessibility Testing

Axe is a widely used accessibility testing engine that integrates with web browsers and development tools. It allows developers to test accessibility during the development process and identify issues early. Many automated accessibility tools and browser extensions rely on the Axe engine to detect accessibility violations.

Learn more: https://www.deque.com/axe/

Lighthouse Accessibility Audit

Google Lighthouse includes an accessibility auditing feature that evaluates webpages against accessibility best practices. Lighthouse provides an accessibility score along with recommendations for improving compliance. Because Lighthouse is built into Chrome developer tools, it is frequently used as an initial accessibility check during development.

Learn more: https://developer.chrome.com/docs/lighthouse/accessibility/

SiteImprove Chrome Extension

The SiteImprove Accessibility Checker is a Chrome extension that scans individual web pages for accessibility issues in accordance with WCAG guidelines. It highlights potential problems directly within the page and provides explanations for each issue along with suggestions for how to fix them. The tool is especially helpful for quickly reviewing accessibility while editing content or developing pages.

Learn more: https://chromewebstore.google.com/detail/siteimprove-accessibility/djcglbmbegflehmbfleechkjhmedcopn

Color Contrast Analyzer (CCA)

The Color Contrast Analyzer, developed by TPGi, helps designers and developers determine whether the color contrast between text and background elements meets WCAG accessibility requirements. The tool allows users to test color combinations and verify that they meet the minimum contrast ratios required for readability by individuals with low vision or color blindness.

Learn more: https://www.tpgi.com/color-contrast-checker/

Polypane Browser

Polypane is a specialized browser designed to help developers build accessible and responsive websites. It allows users to view multiple screen sizes at once while also highlighting accessibility issues such as color contrast problems, missing form labels, and focus visibility. Polypane includes built-in accessibility checks that make it easier to identify problems during the design and development process.

Learn more: https://polypane.app/

Screen Reader Testing

Automated tools cannot detect every accessibility issue. Because of this, accessibility experts often test websites using real screen readers such as NVDA, TalkBack (Android), or VoiceOver (MacOS and iOS). Testing with assistive technologies provides insight into how users with disabilities actually experience a website and helps identify issues that automated tools may miss.

Legal and Compliance Terminology

Accessibility Demand Letters

Accessibility demand letters are legal notices sent to organizations alleging that their website is not accessible to individuals with disabilities. These letters often request that the organization remediate accessibility barriers and may include settlement demands.

Accessibility Lawsuits

Accessibility lawsuits are legal actions filed under the ADA or similar regulations claiming that a website or digital platform prevents equal access for individuals with disabilities. Many of these lawsuits reference WCAG standards as the basis for determining accessibility compliance.

Document Accessibility

Accessible PDFs

Accessible PDFs are documents that are structured so that assistive technologies can properly interpret their content. This includes using tagged headings, providing alternative text for images, maintaining proper reading order, and ensuring accessible form fields.

Accessible Word Documents

Word documents can also pose accessibility challenges if not structured correctly. Accessible Word documents use heading styles, descriptive links, alt text for images, and proper table structures so assistive technologies can interpret the content correctly.

Accessible PowerPoint Presentations

Accessible PowerPoint files ensure that slide content is structured in a logical reading order, images include alternative text, and color contrast is sufficient for readability.

Learn More About Accessibility Standards

For official guidance on accessibility laws and standards, visit:

Americans with Disabilities Act
https://www.ada.gov

Web Content Accessibility Guidelines
https://www.w3.org/WAI/standards-guidelines/wcag/

WCAG 2.2 Standard
https://www.w3.org/TR/WCAG22/

Section 508 Standards
https://www.section508.gov

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