A pingback is one of four types of linkback methods for Web authors to request notification when somebody links to one of their documents. This enables authors to keep track of who is linking to, or referring to their articles.
AddThis, the new brand name for Clearspring Technologies, is the leader in socially connecting publishers, services and advertisers to audiences on the open web. Reaching more than 1.3 billion unique users monthly, AddThis’ social tools and analytics are used on more than 14 million unique domains to distribute and track digital...
Open graph description entity tag
Chrome for Android, since version 39 supports the "theme-color" meta tag to allow websites control the background color of the tab's UI header.
A canonical link element is an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical", or "preferred".