Standard::Markdown

The simplest book on the shelf — one specimen page. Standard renders
CommonMark plus exactly three extensions, all Obsidian-compatible. If it
renders on this page, it is in the standard; if it doesn’t, it isn’t.

Base

Everything in CommonMark: headings, emphasis,
lists, links, images, code fences, blockquotes, tables.

Extension 1 — Callouts

> [!note]
> Obsidian-flavored callouts, any type: note, warning, tip, caption…

Thirteen types render as semantic theme boxes, each with its own symbol:

Any type collapses into an HTML <details> disclosure with a + (open by
default) or - (closed by default) suffix on the type name:

> [!tip]- Click to see the hint
> Collapsed by default to save reading space.

The question type doubles as a flashcard: collapse the answer, and it stays
hidden until clicked — the same mechanic Notion toggle blocks map onto when
ingested. ==highlight== inside a callout compiles to <mark>, same as
anywhere else.

Extension 2 — Wikilinks

A link to [[another-note]] resolves by filename, like Obsidian.

Wikilinks resolve against the vault’s note index when publishing; a link to a
private note degrades to plain text rather than a broken link.

Extension 3 — Footnotes

Typography carries the argument.[^1]

[^1]: The footnote lands at the end of the page.

Typography carries the argument.^[1]

What is deliberately absent

No MDX, no HTML-in-markdown requirements, no proprietary syntax that would
chain a note to one renderer. A Standard note opened in any markdown app in
twenty years should read exactly as written — that’s the norm.

Typographic rendering (smart quotes, thin spaces, the :: patterns) is a
separate concern with its own book: Standard::Syntax.