Unity is a shell interface for the GNOME desktop environment developed by Canonical Ltd for its Ubuntu operating system. Unity debuted in the netbook edition of Ubuntu 10.10. It is designed to make more efficient use of space given the limited screen size of netbooks, including, for example, a vertical application switcher called the launcher. Unlike GNOME, KDE Software Compilation, Xfce, or LXDE, Unity is not a collection of applications but is designed to use existing GTK+ programs.