Hi There USB and Firewire ports are a way of connecting peripherals to your computer and transfering data, photos, digital videos etc to your computer USB1 is the slowest means of transfering data between your devices the next fastest is USB2 and the fastest of the three is firewire. Most peripherals ie cameras, digital videos etc that can connect to USB and bought in the last year or so will more than likly be usb2 although they will still work on USB1 but at the slower transfer rate. If your computer is quite old it may only have USB1 in it. You can get a upgrade card with USB2 and a firewire port on but first you must make sure you have a spare PCI slot inside your PC. I am not sure what speeds these three items transfer data at but no doubt someone will add to this point to let you know.
HOpe this helps
Kindest Regards Tony B.