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.

Glossary terms can be selected from the sidebar (or listed below on mobile devices and other narrow width screens).

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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Endian and endianness (or "byte-order") describe how computers organize the bytes that make up numbers.