I just purchased a firewire 800/400 cable, how do I transfer files from one computer to another?

I purchased the Belkin FireWire 800/400 9-pin to 6-pin cable to transfer files from one laptop to another… how do I do this? I am transfering files from a macbook to a macbook pro.

You’d think for a 33 dollar purchase, the people at the apple store would explain how to use it and not tell you to just “google it.” Whack!!