This is a built-in help article.

Writing articles

Periwiki articles are written in CommonMark Markdown, extended with WikiLink syntax for connecting articles. See Syntax for a quick reference.

Frontmatter

Articles can include optional frontmatter at the very beginning, enclosed in --- fences. Frontmatter uses NestedText format (similar to YAML, but all values are strings — no surprises with wikilinks).

---
display_title: The Common Periwinkle
---

The rest of the article content goes here...

Supported fields

Field Purpose
display_title Override the article's display title (URL remains unchanged)
layout Controls page appearance. mainpage shows "Main page" tab instead of "Article"
toc Set to false to hide the automatic table of contents

Additional fields are preserved for future use.

Why NestedText?

YAML has a footgun: [[wikilinks]] are silently parsed as nested arrays. NestedText treats all values as strings, so wikilinks work naturally:

---
see_also: [[Related Article]]
---

WikiLinks use double-bracket syntax to link between articles:

The common periwinkle, [[Littorina littorea]], is found along rocky coastlines.

This creates a link to the article titled "Littorina littorea", using that title as the link text.

To display text that differs from the destination article's title, use a pipe separator:

The [[Littorina littorea|common periwinkle]] is found along rocky coastlines.

This links to "Littorina littorea" but displays "common periwinkle" to the reader.

It is permissible for [[ Wikilinks | wiki links ]] to contain extra spaces.

Trailing and leading spaces around [[, |, and ]] are trimmed. Extra spaces within the text are left intact.

WikiLinks to articles that do not yet exist are displayed in red, distinguishing them from links to existing content. These are sometimes called "red links." Clicking a dead link takes you to the editor for that article, inviting you to create it.

Table of Contents

Articles containing two or more ## headings automatically display a table of contents before the first heading. To hide the table of contents, add toc: false to the article's frontmatter.

Footnotes

Footnotes allow you to add references or supplementary information without interrupting the flow of text.

The common periwinkle can live for up to 10 years[^lifespan].

[^lifespan]: Smith, J. (2020). "Marine Gastropod Longevity." Journal of Molluscs.

This renders as a superscript link in the text, with the footnote content appearing in a "References" section at the bottom of the article. Clicking the footnote number scrolls to the reference; clicking the backlink (^) returns to the text.

Multiple references to the same footnote are supported:

Periwinkles are herbivores[^diet]. They graze on algae[^diet].

[^diet]: They primarily consume microalgae and diatoms.

When a footnote is referenced multiple times, each backlink is labeled (^a, ^b, etc.) to return readers to the specific location in the text.

Markdown

Periwiki supports standard CommonMark syntax. For the complete specification, see commonmark.org.

Syntax Result
**bold** bold
*italic* italic
[text](url) Hyperlink
# Heading Heading (levels 1-6)
`code` Inline code
> quote Block quotation

For internal links between articles, prefer WikiLinks over standard Markdown links:

<!-- Markdown link (verbose, fragile) -->
For more, see [Periwinkles](/wiki/Periwinkles).

<!-- WikiLink (preferred) -->
For more, see [[Periwinkles]].
Built-in article · updated March 5, 2026 at 11:09 pm What links here? View as Markdown