MediaWiki:Apihelp-query+extracts-param-sectionformat/en

How to format sections in plaintext mode:
 * plain:No formatting.
 * wiki:Wikitext-style formatting (== like this ==).
 * raw:This module's internal representation (section titles prefixed with &lt;ASCII 1&gt;&lt;ASCII 2&gt;&lt;section level&gt;&lt;ASCII 2&gt;&lt;ASCII 1&gt;).