Google APIs are application programming interfaces developed by Google which allow communication with Google Services and their integration to other services.
See what your Facebook friends have liked, shared, or commented on across the Web. This includes all variations of Like, Share and Follow Buttons, Embedded Posts, Comments, Activity Feed, Recommendations Feed, Recommendations Bar, Like Box and Facepile.
nginx [engine x] is a HTTP server and mail proxy server written by Igor Sysoev.
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook
Open graph description entity tag
A canonical link element is an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical", or "preferred".