LinkedIn Plugins are a way to drop LinkedIn functionality into websites.
Google+ platform websites integration using the Google+ platform tag.
Let visitors recommend your content on Google Search and share it on Google+.
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...
Pinterest is a social networking site with a visually-pleasing virtual pinboard interface. Users collect photos and link to products they love, creating their own pinboards and following the pinboards of other people whom they find interesting. The site has experienced rapid growth in recent months.
Content Security Policy is best used as defense-in-depth, to reduce the harm caused by content injection attacks.
Open graph description entity tag
Sites who has this tag are verfied by google to use WebMaster tools