Reference

XML

XML (Extensible Markup Language) is a text-based format that stores structured data inside nested, custom-named tags, such as `<title>…</title>`. It is self-describing and widely used for documents, configuration, RSS feeds, and data exchange between systems.

Files & formatsGeneral

XML

Also known as: XML file, .xml, Extensible Markup Language

Stores data in nested, self-describing tags
Powers RSS feeds, SVG, and office documents
More verbose than JSON but supports schemas

How XML works

XML wraps every piece of data in a matching pair of tags you define yourself, so the markup describes its own content. Tags nest to form a tree, and elements can carry attributes for extra metadata.

Many familiar file types are XML underneath — RSS and Atom feeds, office documents inside `.docx` and `.xlsx`, SVG images, and `.plist` settings on Apple platforms all use XML syntax.

XML vs JSON

Compared with JSON, XML is more verbose because each value sits between an opening and closing tag, which makes files larger but also supports comments, attributes, and formal schemas for validation.

JSON tends to win for web APIs where compactness matters, while XML remains common in publishing, documents, and systems that need strict structure.

Related terms

Keep reading the reference.

Files & formatsJSONJSON (JavaScript Object Notation) is a lightweight, text-based format for storing and exchanging structured data as key/value pairs and ordered lists. It is human-readable, language-independent, and the default format for most web APIs and config files.General Files & formatsHTMLHTML (HyperText Markup Language) is the standard text-based language that defines the structure and content of web pages, using tags like `<p>`, `<a>`, and `<img>`. Browsers read HTML and render it into the pages you see.General Files & formatsSVGSVG (.svg) is a vector image format that stores shapes as math rather than pixels, so it scales to any size without losing sharpness. For logos and icons it is usually tiny, but it is unsuited to photographs, which it cannot represent efficiently.General Web & SEOStructured data (schema markup)Structured data is machine-readable code, usually written in JSON-LD using the schema.org vocabulary, that labels what a page is about — an article, product, recipe, or FAQ. Search engines use it to understand content and to power rich results like star ratings and FAQ dropdowns.General