Xubuntu is a complete GNU/Linux based operating system with an Ubuntu base. It is lighter on system requirements and tends to be more efficient than Ubuntu with GNOME or KDE, since it uses the Xfce Desktop environment, which makes it ideal for old or low-end machines, thin-client networks, or for those who would like to get more performance out of their hardware.
Kubuntu is a user friendly operating system based on KDE, the K Desktop Environment. With a predictable 6 month release cycle and part of the Ubuntu project, Kubuntu is the GNU/Linux distribution for everyone.
Ubuntu 7.04 is the current stable version of the Ubuntu operating system. The common name given to this release from the time of its early development was “Feisty Fawn”.
Ubuntu is a community developed, linux-based operating system that is perfect for laptops, desktops and servers. It contains all the applications you need -- a web browser, presentation, document and spreadsheet software, instant messaging and much more.The most recent version, Ubuntu 7.04 (Feisty Fawn), was released on April 19, 2007.
Today, Thu Apr 19 15:18:16 BST 2007, Ubuntu 7.04 codenamed Feisty Fawn has been released as stable.
Folks, allow me to introduce the Gutsy Gibbon, who will be succeeding the Feisty Fawn as the focus of our development love in a few short weeks, for release in October 2007.” -- Shuttleworth