LinkedIn Plugins are a way to drop LinkedIn functionality into websites.
The Tweet Button is a small widget which allows visitors to share content and connect on Twitter.
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.
Open graph description entity tag
A WebSite is a set of related web pages and other items typically served from a single web domain and accessible via URLs.