AdSense is an ad serving application run by Google. Website owners can enroll in the program to enable text, image, and, more recently, video advertisements on their websites. These advertisements are administered by Google and generate revenue on either a per-click or per-impression basis. Google not only offers AdSense for ...
This script is the defacto way to enable use of HTML5 sectioning elements in legacy Internet Explorer.
Open graph description entity tag
A web page. Every web page is implicitly assumed to be declared to be of type WebPage, so the various properties about that webpage, such as breadcrumb may be used. We recommend explicit declaration if these properties are specified, but if they are found outside of an itemscope, they will be assumed to be about the page
Sites who has this tag are verfied by google to use WebMaster tools