Personal assistant.

Electric Power Steering (EPS) in the
BMW 3 Series Sedan.

To give you more bends per litre, an electric motor is used to assist the steering.* The advantage compared to traditional hydraulic systems is that it only needs electricity when the car is actually changing direction. If the car is travelling in a straight line or round a corner at a constant angle, the electric motor is idle and does not draw any power.

*Only available on certain models.