I was taking a look for questions, and I started to read  thread.  One of the answers says to use the command cat /etc/passwd|grep '/bin/bash', to test if there's other users in the computer. For security purposes, I tested that and I got this:  root:x:0:0:root:/root:/bin/bash nori:x:1000:1000:Nori,,,:/home/nori:/bin/bash   Now, I would like to know, why there is a root user? I thought I only created 1 user.  Also, please note that after installing Ubuntu, my friends (who also use Linux, but not Ubuntu) told me to create a root password (which is different from the user password).  EDIT: To add the root password, I used the sudo -i, and then I used the passwd to create a new password.  Thank you for the help, and sorry if this question have already been answered.
If you use sudo su - or sudo -s you will get the full root certification  "likewise a root user ".  Is this user an official user or is it from canonical?  ~$ sudo su - [sudo] password for username:  root@lp:~# id uid=0(root) gid=0(root) groups=0(root) root@lp:~# pwd /root root@lp:~#
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