How to Login as Root in Ubuntu

lf u want to enable and logon with the root account in ubuntu This will enable the root account.

$ sudo passwd

To enable manual logon with Ubuntu 13.10, open the config file by running the commands below

$sudo gedit /etc/lightdm/lightdm.conf.d/50-unity-greeter.conf
Then add the line below as shown in the image.

greeter-show-manual-login=true

Save the file and restart your computer.
For earlier versions of Ubuntu, you may find this config file in a different location under 

$ sudo gedit /etc/lightdm/lightdm.conf

If you want to lock / disable the root account, run the commands below.

$sudo passwd -l root