If you find yourself being bugged by broken ssh connections from time to time, then you have come to the right place.
Screen is a terminal multiplexer. For detailed information on screen. Please refer to these three great posts.
If you don't like to read through the three listed web pages above, these five commands will get you well started (enough for me).
screen -S sessionName # New a session called sessionName
screen -ls -> List all sessions
screen -r sessionName -> Resume to session sessionName
screen -d sessionName -> Detach from sessionName
Ctrl + a + d # or
screen -d -r sessionName -> Detach from current session and resume to sessionName