Xfce is a lightweight desktop environment for UNIX-like operating systems. It aims to be fast and lightweight, while still being visually appealing and easy to use; thereby directly increasing productivity.
Xfce 4 embodies the goal of the traditional UNIX philosophy of modularity and re-usability. It consists of a number of components that together provide the full functionality of the desktop environment. Many are packaged separately and you can pick and choose from the available packages to create the best personal working environment.
Another priority of Xfce 4 is adherence to standards, specifically those defined at freedesktop.org.
Xfce 4 can be installed on several UNIX platforms. It is known to compile on Linux, NetBSD, FreeBSD, OpenBSD, Solaris, Cygwin and MacOS X systems, on x86, PPC, Sparc, Alpha processors.