Explanations about the root account.
What is root?
Root is the name of the most powerful account on a Debian installation. This user account can do everything on the machine. It's also known as supervisor, administrator.
It has uid 0 and gid 0.
At installation time, you are been asked for creation or not of the root account.
if you want so (the default), you'll be asked to provide a password for root. Use a strong one!
- if not, no root account is enabled and the password of the first user created will be used for administration tasks.
[http://www.debian.org/doc/manuals/reference/ch-tutorial.en.html#s-login-root Login to a shell prompt as root]
[http://www.debian.org/doc/manuals/reference/ch-tips.en.html#s-crackroot "I forgot the root password!"]