Stepper motor questions

I have been looking around at/for stepper motors.
I see that there are 4,6,8 wire motors.
Stepperworlds Controller board has connection for 6 wires.
hobbycnc board seems to work with 5,6,8 wires.
Xylotex seems to work with 4 wire.
My question is this, what is the diffrence between a 4,5,6,8 wire
motors? I would asume that each pair of wire would make up a coil
loop inside the motor. And the 4 wire motors have two loops.
and the 8 wire would have 4 loops that you would take the opposing
coil and hook up in reverse to the controler. But I'm am confussed
with 6 wire motors how would you hook these up to a 4 connector board?
If some one could explain the differnce between 4,6,8 wire motors and
how to hook them up to a 4 and 6 connector board it would add to my
understanding.....



Thanks


Jerry