MDN Web Docs Glossary: Definitions of Web-related terms

Web technologies contain long lists of jargon and abbreviations that are used in documentation and coding. This glossary provides definitions of words and abbreviations you need to know to successfully understand and build for the web.

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Note: This glossary is a never-ending work in progress. You can help improve it by writing new entries or by making the existing ones better.

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Visual Viewport: The portion of the viewport that is currently visible is called the visual viewport. This can be smaller than the layout viewport, such as when the user has pinched-zoomed. The visual viewport is the visual portion of a screen excluding on-screen keyboards, areas outside of a pinch-zoom area, or any other on-screen artifact that doesn't scale with the dimensions of a page.