nginx [engine x] is a HTTP server and mail proxy server written by Igor Sysoev.
websites using the $ symbol on their website - meaning it may accept payment in this currency used in Israel.
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.
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