AutoElecHack:
One question then, what is the difference between a servo motor and a stepper motor? Would a servo be considered a digital version of a stepper which is analogue?
Well, a stepper is more like a digital device. you move it in discrete steps. You supply voltage to the coils in a series of different configurations, and it causes the motor to move a very small amount (some will move less than 1 degree per step).
A servo is more like analog, in that you supply a voltage, and the motor begins to move. A servo requires feedback to tell the controller where it has moved to. This can be in the form of a shaft encoder (which can show a direction and amount of movement, or, alternatively, an absolute position), or a linear encoder that can tell the controller how far the moving part that is driven by the motor, has gone. A potentiometer can be used to show position, but it's not common. The controller uses the position information to speed up, slow down, or stop the motor, according to where it's target position is.