Facebook's Like button is the quickest way for people to share content with their friends. A single click on the Like button will 'like' pieces of content on the web and share them on Facebook. You can also display a Share button next to the Like button to let people add a personal message and customize who they share with.
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
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook
Any offered product or service. For example: a pair of shoes; a concert ticket; the rental of a car; a haircut; or an episode of a TV show streamed online.
A canonical link element is an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical", or "preferred".
By adding rel="home" to a hyperlink, a page indicates that the destination of that hyperlink is the homepage of the site in which the current page appears.