The sudo (sudouser do) command is a tool in Linux systems, used to run commands or programs as another user, by default as root user. If you doing administration task then you need to use sudo frequently. This article show you how to run sudo command without entering password. To grant the sudo access to
sudo - DesignLinux
Su Command in Linux (Switch User)
The su command is used to run commands as a another user. It is simplest way to switch to the administrative account in the current login session. It is very useful when the root user is not allowed to log in to the system through ssh. For example, in Ubuntu, root user is disabled by