Wiki markup is a curious text encoding phenomenon: every wiki has it, and they all use markup to produce essentially the same results, but many wikis uses different symbols to produce the same effects. In MediaWiki one surrounds their sub-headings with = like so: =subheading1= or ==subheading2==. The same effect is had in PBWiki with this syntax: !subheading1 or !!subheading2. Similarly, an editor of MediaWiki designates bold words by surrounding them with three apostrophes, while PBWiki editors use two asterisks. Both wikis are coding for the same end result but using different symbols to get the same effect.

Starter links: MediaWiki markup syntax | PB Wiki markup syntax | Meatball wiki’s attempt to address this problem