nginx [engine x] is a HTTP server and mail proxy server written by Igor Sysoev.
A family of standard web feed formats used to publish frequently updated information like blog entries, news headlines, audio and video.
UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is the preferred encoding for web pages.
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