Some usage tips for ubuntu

1. Ubuntu uses sudo instead of the usual su command to gain root privilege. To avoid sudo, just issue

sudo passwd root

then update the root password and the usual su command works.

2. Just like windows system, we could modify the hosts.conf file to block the access to some specific website (This will work partially to get rid of web addiction :-) ).

# gedit /etc/hosts

then add the following command in the hosts.conf file

127.0.0.1 the website you intended to block

That is it.