Correct. In the front of the car you have a screen and keyboard.

The Euro version of the nav system uses the following components, of which not all are fitted to all cars:

On-board monitor (screen, keyboard & tapedeck)
Multi-function steering wheel (optional)
Rear audio system controller (Rear Multi-Info Display, optional)
Rear screen (optional, for TV/video only)
Navigation computer (the actual CD or DVD drive)
GPS receiver (if you have a Mk1 or Mk2, with Mk3 or Mk4 this is built into the nav drive)
Video module (TV tuner, optional)
Reverse camera (optional)
DVD video player or Video tape deck (optional)
Radio module (radio tuner)
CD changer (either MP3 or standard)
Telephone (optional)
Amplifier (either DSP or standard)

In Japan, they have an extra VICS traffic info receiver module

As you can see, there are lots of options!
Someone highlight anything I've missed :-)