Retrieving email from hosted server

Hi, I am getting confused on how to do this. I have an email box set up on my hosted shared server account. From the server at my office I would like to run a php script that retrieves the emails, reads them, then performs some functions based on what's in the email messages. I have been looking at the php imap functions. So do I need to have the imap module installed on my office server, the hosted server, or both?

You need the php imap module on the server that runs the php code.

Your hosted email server must support imap.