The text/Markdown Media Type
RFC 7763 defines the "text/markdown" media type for Markdown documents, specifying that multiple Markdown formats (variants) exist and must be indicated via a "format" parameter. The document establishes a registration procedure for new format identifiers and outlines security considerations for Markdown content.
Background
This RFC (Request for Comments) is an official Internet standard — published by the IETF, the organization that sets core technical standards for the Internet — that formally registers Markdown as a standardized media type (i.e., a way for computers to announce what kind of content they're sending). Before this, Markdown had no official "text/markdown" label, causing interoperability problems: email clients, browsers, and code repositories couldn't reliably tell whether a file was Markdown or plain text. The document also clarifies that Markdown has no single canonical specification — there are many variants (GitHub-Flavored Markdown, CommonMark, etc.) — so the media type alone doesn't guarantee how a file will render. This matters for anyone building tools that process .md files, as it provides a consistent way to identify Markdown content across the web.