Difference between su and sudo su [duplicate]

Asking because of curiosity. :)

When I type

sudo su

It asks for my user password. And when I type just

su

It asks for the root user password. But both the commands directs me to the root terminal. Then why is there such a difference?

Solution 1:

sudo su means run the command su as sudo which means as root. Here the system will ask you for your password since you are a sudoer. After you enter your password, you now have root privileges. So su command won't ask for a password. It's same as if you are a root then su to any other user will not ask for password because you are a root.

When you just run the command su, you are running it as a regular user. Since su means switch to user root, you will be asked for the root password.