Glossary

Searchable terminology from accessibility, web standards, and related fields.

77 results found in web development.

DOM (Document Object Model)
A programming interface that represents an HTML or XML document as a tree structure of objects, where each node corresponds to a part of the document such as elements, attributes, and text content. Th…
DOM Tree (Document Object Model, DOM)
A programming interface that represents an HTML or XML document as a hierarchical tree structure, where each node corresponds to a part of the document such as an element, attribute, or text content. …
Decorative Image (Decorative Graphic, Presentational Image)
An image that serves a purely aesthetic or visual design purpose and does not convey meaningful information to the user. According to WCAG guidelines, decorative images should receive empty alt text (…
Delivery Context
Delivery context is a term defined by the W3C Device Independence Working Group to describe the set of attributes that characterize the environment in which web content is delivered and consumed. This…
Device Independence (Device-Independent Design, Input Agnostic Design)
A web design principle that ensures content and functionality are accessible regardless of the input device or interaction method used to access them. Device-independent design avoids assumptions abou…
Device-Dependent Event Handler (Device-Dependent Event, Mouse-Dependent Event Handler)
An event handler in web development that is triggered only by a specific input device, such as a mouse click or touch gesture, rather than being accessible through multiple input methods. Device-depen…
Dojo Toolkit (Dojo)
An open-source JavaScript toolkit for building Ajax web applications, notable in accessibility history for being one of the first major frameworks to incorporate WAI-ARIA support. In 2006, IBM contrib…
Dynamic HTML (DHTML)
A collection of technologies — including HTML, CSS, JavaScript, and the Document Object Model (DOM) — used together to create interactive and animated web content that can change after a page has load…
Form Label (Input Label, Form Field Label)
A text label programmatically associated with an interactive form control (such as a text input, button, checkbox, or dropdown) that identifies the purpose or function of that control to all users. In…
Functional Image
An image that serves as an interactive control, such as a link, button, or form input, rather than simply conveying information. When an image is used as a link or button, its alternative text must de…
Graceful degradation (Graceful degradation)
A design strategy in which web content built with newer or advanced technologies continues to function and remain accessible when those technologies are not supported by a user's browser or assistive …
HTML (HyperText Markup Language)
The standard markup language used to create and structure content on the World Wide Web. HTML uses elements (tags) to define the semantic structure of documents, including headings, paragraphs, links,…
HTML Canvas (Canvas API, Canvas Element)
An HTML element used to draw graphics on a web page via JavaScript, rendering content as a bitmap image rather than as structured DOM elements. Unlike SVG, canvas content is not inherently accessible …
Heading hierarchy (Heading structure, Heading levels)
The logical, nested structure of HTML heading elements (h1 through h6) that organizes web content into a navigable outline. A well-structured heading hierarchy uses heading levels sequentially without…
Hijax (Progressive enhancement with Ajax)
A web development approach coined by Jeremy Keith that applies progressive enhancement principles to Ajax applications. Hijax starts with a fully functional, accessible HTML page and then layers Ajax …
IDE (Integrated Development Environment)
A software application that provides a comprehensive environment for writing, testing, and debugging code. Common IDEs include Visual Studio Code, IntelliJ IDEA, and Xcode. In accessibility contexts, …
Image Map (Clickable Map, Imagemap)
An HTML feature that allows different regions of a single image to be designated as separate hyperlinks, each pointing to a different URL. Image maps can be client-side (coordinates and links defined …
Internationalization (i18n)
The process of designing and developing software, websites, or applications so that they can be adapted to different languages, regions, and cultural conventions without requiring engineering changes.…
LLM Accessibility (AI-Generated Accessibility, Generative AI Accessibility)
The study and practice of how large language models (LLMs) and generative AI tools handle digital accessibility in their outputs, particularly when generating code, user interfaces, or content. Resear…
Landmarks (ARIA Landmarks, Page Landmarks, Landmark Regions)
Designated regions of a web page that provide structural navigation points for assistive technology users. ARIA landmark roles include banner, navigation, main, complementary, contentinfo, search, for…