ssh - is a program for logging into a remote machine and for executing command on a remote machine.
Format: ssh [-l login_name ] hostname [command]
Eg1: ssh –l root 192.168.1.2
Here the current working machine login to remote machine which has the
ip192.168.1.2 and with the username root.
Eg2: ssh –l root 192.168.1.3 –X
Here it allows you to run the graphical mode too in the remote computer 192.168.1.3 which is logged in with username root.