Unison synchronizes two file trees. Thus if you want to backup your work files to a central place rather them lying around on all different machine; unison is for you. We will call the machine you want to get the files from as CLIENT and machines where files are centrally located as SERVER.

Firstly you need to apt-get (or install) unison on all the machines you want to save files back anf forth. This can be simply done by opening a shell and typing
$ sudo apt-get install unison
for text-interface or
$ sudo apt-get install unison-gtk
for a graphical user interface.

Now to unison to a remote machine; we need to test the version of unison running on the server and the client by
$ssh remotehostname unison -version
and
$unison -version
and make sure they are the same version

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