I'll tell you what I know
There is USB 1.0 which run at about 12 mb/s, USB 2.0 at about 400 mb/s.
Also there are different USB connectors, there is connector A, B, And the mini USB connector (used for digital cameras and stuff).
If you check your Printer or scanner USB cable you will find one end with A connector and the other end with B connector.
Firewire runs at about 400 mb/s.
it has 2 connectors, one uses 6 pins (you plug it in your PC) and ther other uses 4 pins (For cameras and stuff).