Google Publisher Tag (GPT) is an ad tagging library with which you can dynamically build ad requests. GPT takes key details from you such as ad unit name, ad size, and custom targeting, builds the request, and displays the ad on web pages or mobile apps.
nginx [engine x] is a HTTP server and mail proxy server written by Igor Sysoev.
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.