Many modern Linux distributions, in the interest of security I guess, have made the root account hidden and without a password. So even if you drop to a terminal and try to log in as root you can't. I know it is very easy to add a root password it does defeat the design philosophy of the distribution. Instead they have a super, power or administrative account that is usually the first one activated.

This account is able to do everything that the root account can do with one difference. Whenever the account needs to do something system related, that accounts password is requested. This is done via a program called "sudo" which stands for "SUperuser DO". This "sudo" program is a very flexible and dangerous program and if configured incorrectly will open up holes in your computers security big enough to drive a semi-trailer through. It is therefore important to understand what this program does and how it is used.

This program acts as a go between for the user and system. It provides an extra layer of protection to prevent such fumble fingered errors like "rm -rf /".

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