Dom Glossary

Browse 8 dom terms defined in plain English, from the cultural dictionary of computing.

8 Dom Terms

Child Element: An element directly contained within another element in a document tree or component hierarchy. Child-element relationships matter in layout, selectors, event...
Mutation Observer: A browser API that watches for changes to the DOM tree — added/removed nodes, attribute changes, and text content modifications. Replaced the deprecated...
Portal: A mechanism in React (and similar UI frameworks) that renders a child component into a DOM node outside its parent's hierarchy, while preserving the original...
Ref: In React, a mutable container object (created via useRef or createRef) that holds a .current value persisted across renders without triggering re-renders —...
Render Tree: The browser's internal representation that combines the DOM tree with computed CSS styles, containing only the visible elements (excluding display:none nodes...
Scroll Event: A browser DOM event fired when the user scrolls an element or the page, notorious for triggering at extremely high frequency and requiring throttling or...
Testing Library: A family of testing utilities (most notably @testing-library/react) that encourages testing UI components the way users interact with them — querying by...
Window: The global object in browser JavaScript that represents the browser tab or frame, providing access to the DOM (document), navigation (location), timers...