NonHTML

NonHTML refers to content, markup languages, or data formats that are not HTML. It encompasses formats used for information exchange, data representation, or alternate markup syntaxes on the web and in digital documents.

Common examples include XML-based languages such as SVG for vector graphics, MathML for mathematics, and RSS or Atom feeds for syndication. XHTML is a variant of HTML written with XML syntax, while still serving as a markup for web documents. For data payloads, JSON and YAML are widely used in web APIs and configuration, even though they are not markup languages for rendering pages.

Delivery and rendering depend on MIME types. NonHTML content is retrieved with content types like image/svg+xml for SVG, application/rss+xml or application/atom+xml for feeds, application/xml or text/xml for general XML, and application/json for JSON. Web browsers render some nonHTML formats directly (SVG, MathML where supported) but many are consumed by scripts or servers rather than displayed as pages.

In practice, nonHTML content coexists with HTML. Developers often use HTML as a presentational layer, with nonHTML formats providing data sources or alternate representations. They are standardized by W3C or other bodies; XML and JSON have formal specifications and ecosystem tooling.

In summary, nonHTML covers a family of formats that extend or replace HTML in specific roles, from vector graphics and math rendering to feeds and data exchange, reflecting the diverse ways information is structured and delivered on the web.