Content Security Policy is best used as defense-in-depth, to reduce the harm caused by content injection attacks.
Any offered product or service. For example: a pair of shoes; a concert ticket; the rental of a car; a haircut; or an episode of a TV show streamed online.
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
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.
A canonical link element is an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical", or "preferred".
Open graph description entity tag