From Fedora Project Wiki
XFCE
About
Xfce is a lightweight desktop environment which aims to be fast and lightweight, while still being visually appealing and user friendly. It consists of a number of components that provide the full functionality which can be expected of a modern desktop environment. Each component is packaged separately so it can be adjusted it to optimal working environment suited to your needs. Xfce also is adhereance to standards, specifically those defined at | freedesktop.org.