Nginx (pronounced "engine x") is a web server with a strong focus on high concurrency, performance and low memory usage. It can also act as a reverse proxy server for HTTP, HTTPS, SMTP, POP3, and IMAP protocols, as well as a load balancer and an HTTP cache.Created by Igor Sysoev in 2002, Nginx runs on Unix, Linux, BSD variants, Mac OS X, Solaris, AIX, HP-UX, and Microsoft Windows. Released under the terms of a BSD-like license, Nginx is free and open source software.