New Dell netbook,Ubuntu,Debian and factory su password.

[Luis Maceira <luis_a_maceira@yahoo.com>]

As a Debian user since 2005 last week I bought a Dell netbook running Ubuntu
(since it is Debian based),but I am unable to do administrative tasks:
upgrading,become su etc. because I cannot find the su password in the docs
that come with the netbook.Is there any standard password that we use 
in these cases,so after we can choose our own su password?