Nginx

Nginx (pronounced "engine x") is a web server. It can 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, OS X, Solaris, AIX, HP-UX, and Windows. Released under the terms of a BSD-like license, Nginx is free and open source software.

Features

Nginx can be deployed to serve dynamic HTTP content on the network using FastCGI, SCGI handlers for scripts, WSGI application servers or Phusion Passenger modules, and it can serve as a software load balancer.

Nginx uses an asynchronous event-driven approach to handling requests, instead of the Apache HTTP Server model that defaults to a threaded or process-oriented approach, where the Event MPM is required for asynchronous processing. Nginx's modular event-driven architecture can provide more predictable performance under high loads.

According to Netcraft's October 2015 Web Server Survey, Nginx was found to be the second most widely used web server across all "active" sites (15.33% of surveyed sites) and for the top million busiest sites (23.66% of surveyed sites). According to W3Techs, it was used by 29.7% of the top 1 million websites, 39.5% of the top 100,000 websites, and by 47.6% of the top 10,000 websites. According to BuiltWith, it is used on 36.6% of the top 10,000 websites, and its growth within the top 10k, 100k and 1 million segments increased. Wikipedia uses Nginx as its SSL termination proxy. As of OpenBSD release 5.2 (1 November 2012), Nginx became part of the OpenBSD base system, providing an alternative to the system's fork of Apache 1.3, which it was intended to replace, but it was later replaced by OpenBSD's own httpd(8).