Linux - persistent sessions

sometimes it takes a long while for a task to run. It is possible to open a screen in Linux and let it continue to run after you close out your session to the machine. Then you can logon again later, switch to the screen and check the progress.

create/open a new screen:

    screen

Leave a screen open:

    CTRL+A, CTRL+D

list open screens:

    screen -ls

switch to a screen:

    screen -r 

close the screen:

    exit