The main function of the steering wheel is to change or maintain the direction of the car. The front wheels turn to the left or right as steered by you. 

When holding the steering wheel , keep a gentle but firm grip. When changing gears hold should be at 12 noon position. Avoid turning the wheel while the car is stationery. Steer when the wheels are rotating  as this minimizes wear and tear on the steering mechanism.

While turning a corner,the outer front wheel moves faster than the inner front wheel and the inner rear wheel slows own to compensate with the outer rear wheel.

The steering wheel can convey many things about the car and the road conditions.A pull to one side indicates a tyre puncture.Similarly , a pull when brakes are applied indicates  badly adjusted brakes.