Floodlight is an optional feature in DFA that allows advertisers to capture and report on the actions of users who visit their website after viewing or clicking on one of the advertiser's ads. For the implementation of Floodlight, Floodlight tags must be placed on the advertiser's webpages.
Open graph description entity tag
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.