Type man screen to find out more or read this screen man page.

Simple scenario:

ssh into your remote box. Type screen Then start the process you want.

Press Ctrl-A then Ctrl-D. This will "detach" your screen session but leave your processes running. You can now log out of the remote box.

If you want to come back later, log on again and type screen -r This will "resume" your screen session, and you can see the output of your process.