Hello Mohammad,
If you are going to update existing installations, it all depends on what you select in the
last step of the configuration process. Basically, you have three options - update everything, update everything except security settings (i.e. passwords and permissions), or skip updating settings (in which case only the program files themselves will be updated). There is a table on the page that lists all possible combinations, see the link above.
Here by "updating" I mean not only product version update, but also deploying a new package of the same version, which might be the case if you want to update Host settings on already deployed Hosts.