Figures 1 through 5 picture the features and operation of Screen. Looking at Figure 1
assume that you have used SSH to log in to a remote host. Initially, you have your
original shell on your local host (say, your laptop or desktop) and a remote shell. As
usual, you can use the remote shell to run commands on the remote host; output is
encrypted and sent over the SSH connection to your local shell. (In the figures, blue
highlights the shell output that is currently visible.) As lamented above, if your local
shell or the remote shell or the connection between the two is terminated, the
remote shell is terminated, taking your work to the big bit bucket in the sky.