nginx [engine x] is a HTTP server and mail proxy server written by Igor Sysoev.
UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is the preferred encoding for web pages.
The http-equiv attribute provides an HTTP header for the information/value of the content attribute. The http-equiv attribute can be used to simulate an HTTP response header.
By adding rel="home" to a hyperlink, a page indicates that the destination of that hyperlink is the homepage of the site in which the current page appears.
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook