Microdata or rich snippets are additional information about your content such as names, descriptions, dates and ratings that are displayed on a search engine results page like Google or Bing to draw attention to your products/news and then be able to increase the conversion rate.
Microdata is a new feature recently added to Joomla! 3.3. Not all templates provide microdata support, but JoomlaShine templates do.
You can enable/disable the microdata semantics output from the Article editing options to add information you want to every article of the site. And our JSN templates will show the information automatically. You can check the source code via this testing tool.