The Platform for Privacy Preferences Project (P3P) enables Websites to express their privacy practices in a standard format that can be retrieved automatically and interpreted easily by user agents. P3P user agents will allow users to be informed of site practices (in both machine- and human-readable formats) and to automate dec...
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
Open graph title 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
A scheme.org entity that represents an organization such as a school, NGO, corporation, club, etc.
A scheme.org entity that represents a person (alive, dead, undead, or fictional).
This page contains a meta robots tag which tells search engines and robots to index or not index the page.
Meta descriptions are HTML attributes that provide concise explanations of the contents of web pages. Meta descriptions are commonly used on search engine result pages (SERPs) to display preview snippets for a given page.
Sites who has this tag are verfied by google to use WebMaster tools
A canonical link element is an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical", or "preferred".