Becoming Root User Without Password In GNU/Linux Ubuntu

Ubuntu has an excellent security tool called sudo that allows the administrator to delegate control of certain commands to certain users. But to use it you must type the sudo word before any command, and validate (and confirm) it with your system account password. But... some users (like me) wants a more faster solution to become root user simply typing the su command.

If you're using Ubuntu, the sudoers file contains a sentence like this: