In GUI applications the common way to gain root privileges is to start it as root, but there are several security risks in doing this method and it does not allow a good actions mapping. There is no way to separate actions like package-install of system-upgrading. All the users who want to use it must have the root password. Another common approach is using sudo but once you start an application with sudo you will have all the rights the root user will have. If for example the GUI application has a dialog to select files that dialog is running as root which means that the user might be able to delete any file on his machine or even coping others user files.