As explained in the documentation about how PieCrust works, the page contents that you write go through a formatter before the page is rendered or baked. PieCrust ships with 2 standard formatters: Markdown and Textile.

The formatter used on a page is determined by the format setting in the page’s configuration header:

* `markdown` for Markdown
* `textile` for Textile

If unspecified, the extension of the page file is matched against the site/auto_formats setting in the site configuration:

* `.md` for Markdown
* `.textile` for Textile

Otherwise, the site/default_format setting in the site configuration will be used, and that’s Markdown by default.

For a list of valid formatter names, see the formatters reference.