A family of standard web feed formats used to publish frequently updated information like blog entries, news headlines, audio and video.
A pingback is one of four types of linkback methods for Web authors to request notification when somebody links to one of their documents. This enables authors to keep track of who is linking to, or referring to their articles.
nginx [engine x] is a HTTP server and mail proxy server written by Igor Sysoev.
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
A scheme.org entity that represents an organization such as a school, NGO, corporation, club, etc.
Sites who has this tag are verfied by google to use WebMaster tools