create new user

two users on judson: john and sam

ssh to judson from racer, two windows, one as john, one as sam

start bash session, start jobs

ps o pid,user

see what pts/0 session id is

===== Root Password =====

In Ubuntu, by default, there is no root password.  Remember, during installation it did not ask you to create a root password.

Therefore you cannot:
  * login as root
  * use the "su -" command to become the root user.

Though you can:
  * use sudo to run a privileged command, with your own password

You can also (though NOT recommended):
  * $ sudo -i           # run login shell as root
  * $ sudo -s           # run shell as root
  * $ sudo bash         # run shell as root
  * $ sudo passwd root  # set the password for root user

The root user's home directory is /root, not /home/root.
This is where you find .profile and .bashrc for the root user, should you choose to open a shell as root.

===== User Management =====

  $ adduser   # create a new user
  $    # create a group
  $    # add a user to a group
  $ passwd <user>   # reset the password for a user
  $                 # reset my own password
  $                 # add a user to the sudo group
  $ sudo -s -u sam  # run shell as a different user