When parking, try and do this well away from bends, junctions and hilltops. These are all places where the driver's view is already restricted and parking your car in an unsafe place will increase the danger by focing others on the wrong side of the road.
This video clip shows the correct way to secure your vehicle when parking uphill.
If your handbrake fails the gear should still hold the vehicle but if all fails, because you have turned your wheel the vehicle will not roll because it will rest on the kerb.
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