The concept
The parking brake is primarily intended to prevent the vehicle from rolling while parked; it brakes the rear wheels.

See also:
SPORT+
Sporty driving with optimized chassis and suspension
with limited driving stabilization.
The driver handles several of the stabilization
tasks.
Activating SPORT+
Press the button repeatedly unt ...
Sitting safely
The ideal seating position can make a vital contribution
to relaxed, fatigue-free driving.
The seating position plays an important role in
an accident in combination with:
▷ Safety belts.
...
Even more entertainment at the wheel: with BMW Live and BMW Online
Subject to owning a suitable internet-compatible mobile phone and arranging a
requisite data tariff, new BMW 3-Series Sedan customers can enjoy a selection of
services from the existing BMW Online ...
