Quantcast helps advertisers and publishers better understand, find and access targeted audiences in real-time. Marketers use Quantcast to amplify their targeting and reach consumers who look just like their best performing customers with unprecedented performance and scale. Publishers use Quantcast to directly measure and packag...
Allows a website to define how a page is rendered in Internet Explorer 8, allowing a website to decide to use IE7 style rendering over IE8 rendering.
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
Meta Keywords are a specific type of meta tag that appear in the HTML code of a Web page and help tell search engines what the topic of the page is.
Sites who has this tag are verfied by google to use WebMaster tools