After installing The X Server the default window manager (Tab Window Manager, or TWM) just isn't going to cut it. Most users will have some experience with big desktop environments like KDE, GNOME, and Xfce. One component of those larger desktop suites is called the window manager (or WM for short). A window manager is responsible for the appearance and placement of the containers (or "windows") inside which programs run. Openbox is a minimalistic, no-frills-attached window manager.