Small but Powerful

Nginx (pronounced Engine-ex) is an Open Source HTTP server and reverse proxy. The Nginx web server is known for its high performance, stability, rich feature set, simple configuration, and low resource consumption. Nginx, which was written by Igor Sysoev, is used with many high-profile sites, including WordPress.com, Hulu, and LinuxQuestions.org. In addition to its HTTP-related functionality, nginx can also serve as an IMAP/POP3 proxy.

Nginx's basic HTTP support includes the ability to serve static files, accelerated reverse proxying with optional caching, simple load balancing and fault tolerance, remote FastCGI with caching/acceleration, and SSL/TLS server name indication (SNI). Like Apache's httpd, nginx has many features that are implemented in a modular fashion and only need to be enabled if you plan to use them. Unlike the process-based httpd, though, nginx is asynchronous. The main advantage of the asynchronous approach is scalability. In a process-based server, each simultaneous connection requires a thread, which can lead to significant overhead, especially when under high load. An asynchronous server, on the other hand, is event-driven and handles requests in a single (or at least very few) threads.

Installation

If you have a simple site or are starting from scratch, it's very possible you can completely forgo Apache and just use nginx for all your HTTP needs. If you choose to go this route, I recommend you visit the nginx Modules page [2] and verify that all the functionality you require is available with an nginx module. This article describes the common case of nginx acting as a load balancing reverse proxy to multiple existing Apache httpd back-ends. Nginx will serve some static content and then automatically gzip the dynamic content it is proxying from httpd.

[...]