There is no specific command to logout in an Ubuntu system. Why ? Here’s how it works. The desktop you’re seeing is a separate software. They are called Desktop Environments (DE). The default DE of Ubuntu is Unity from Ubuntu’s 11.04 versions. Before it was GNOME. There are many DEs for Ubuntu. Some of them are : Openbox XFCE LXDE and many more.. There are also separate Login Managers to provide the login screen while Ubuntu is loaded.... [READ MORE]