Xen is a virtual-machine monitor for x86, x86-64, Itanium and PowerPC 970 architectures. It allows several guest operating systems to execute on the same computer hardware concurrently. The University of Cambridge Computer Laboratory developed the first versions of Xen; as of 2010 the Xen community develops and maintains

Lighttpd is a secure, fast, standards-compliant web server designed for speed-critical environments. This tutorial shows how you can install Lighttpd on a CentOS 5.4 server with PHP5 support (through FastCGI) and MySQL support.