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.
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.
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook