Markdown-alike languages

Online real-time compiler : Dillinger;

Compare output of multiple compilers : Babelmark;

See concentrated info page by Xrud.

Markdown
John Gruber's initial markdown.

See also Mermaid diagram/flowchart syntax, and markdown-it-container for shortening of some HTML entities.

Common Mark *
Specification.

Implementations by Common Mark.

GitHub Flavored Markdown
Specification.

Xrud info page is rendered by GitHub.

Discord "Markdown 101"
= black strike-out spoiler.

= do not Embed.