How to Use the root account to enter ubuntu

How to Use the root account to access ubuntu after ubuntu is installed is a common user, because the root user is not enabled to use: sudo passwd root set the root password and set the root password. Then you can use it: the su root command enters the root user. However, you can only use the root account in the terminal, and some software cannot run. For example, cutecom can run, but ttyUSB0 cannot be enabled, and you do not know what the problem is. As long as you use root to run it correctly, it's strange. So I thought we would use root to enter the graphic interface. Run vi/etc/lightdm. [SeatDefaults] greeter-session = unity-greeteruser-session = effectugreeter-show-manual-login = tureallow-guest = false autologin-user = root appears in the conf file. This is what I forgot before configuring. now, change to this. Then restart and the system will automatically enter the root account. So enjoy it