screen
screen, formally known as GNU Screen, is a terminal multiplexer, a software application that can be used to multiplex several virtual consoles, allowing a user to access multiple separate login sessions inside a single terminal window, or detach and reattach sessions from a terminal. It is useful for dealing with multiple programs from a command line interface, and for separating programs from the session of the Unix shell that started the program, particularly so a remote process continues running even when the user is disconnected.
Released under the terms of version 3 or later of the GNU General Public License, GNU Screen is free software.
Start a screen
session
screen
Attach to an existing screen session
screen -x