This plugin is well defined by its author as a WordPress plugin designed to allow site admins to sort posts by a new factor: engagement. Engagement is defined by the pl and name of this plugin is “Order By Engagement”.
Engagement is defined by the plugin in three ways: landing on a post from another referring URI, engaging in any social media integrating on the site, or any other hook that calls the modify_engagement() function.
The plugin keeps track of engagement using custom post meta. Posts that then be looped in ascending or descending order using the get_engaged_posts() function to modify the main WordPress $post query. Imaging all the things you can do with posts in order by engagement.
You Can download the plugin here