liudr:
My understanding is very limited. I thought the steering column turns gears that turn the front wheels. The power steering pump gets input from the steering column turning and assists with hydraulics so the driver doesn't have to turn so hard. I will see if the last 25% of my car manual has any details.
Actually, you turn the wheels. XD
The steering wheel is attached to the steering column which has a pinion gear on the end which moves the rack (we're talking rack and pinion here). The rack pushes and pulls the spindles via the tie rod ends. Power steering simply boosts this and makes it easier. Electronic rack and pinion uses electric motors in the unit to help. Some use an electric pump to run a hydraulic boost system.
Your hands do have a mechanical connection to the wheels.