Screen is a program that allows you to log in to a server, start a job, then log out without the job stopping. This means you can run your jobs without having to leave your computer on.

So ssh to e.g. mscoc1:

ssh yourusername@mscoc1.bch.ed.ac.uk

Then start the program Screen:

screen

This will start a Screen session inside your active terminal. If you cd to whatever directory you want to work in, start whatever command you want, then disconnect the screen using Ctrl-A (together) then D, you can log out (but as far as the job is concerned it thinks you're still connected so keeps going).

To reconnect to your screen session, login to the computer you started the job on, and type:

screen -Rd

BE SURE TO KEEP TRACK OF YOUR RUNNING SCREEN SESSIONS - remember every time you do Ctrl-A-D Screen is still there in the background ... to actually END a Screen session you need to type 'exit'. The -Rd option only works if you have left one, and only one, Screen session running. So don't start multiple Screen sessions. 

screen --help for more options.