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 ...
Content Security Policy is best used as defense-in-depth, to reduce the harm caused by content injection attacks.
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
Sites who has this tag are verfied by google to use WebMaster tools
When running in a browser on a mobile phone, "format-detection" meta tag determines whether or not telephone numbers in the HTML content will appear as hypertext links. The user can click a link with a telephone number to initiate a phone call to that phone number.