When you run an application that requires root privileges, sudo will ask you to input your normal user password. This ensures that rogue applications cannot damage your system, and serves as a reminder that you are about to perform administrative actions which require you to be careful!
To use sudo when using the command line, simply type "sudo" before the command you wish to run. Sudo will then prompt you for your password.
Sudo will remember your password for a set amount of time. This feature was designed to allow users to perform multiple administrative tasks without being asked for a password each time.
Note: Be careful when doing administrative tasks, you might damage your system!
Your password will not be shown on the screen as you type it, not even as a row of stars (******). It is being entered with each keystroke!
To use sudo on the command line, preface the command with sudo, as below: Example #1
sudo chown bob:bob /home/bob/*
sudo /etc/init.d/networking restart
To repeat the last command entered, except with sudo prepended to it, run:
Administrator sudo password in Ultra OS is ultra
For more information please visit: https://help.ubuntu.com/community/RootSudo
26th of June, 2011