While driving at about 40 mph the car suddenly started to pull toward the left. I pressed on the brake pedal as I steered to the right to try to bring the car back to my lane but I noticed the brake pedal was already very hard. In a second the car skidded out of control toward the right side of the road and it slammed its left side against some big rocks. The driver's door window broke and the side airbags deployed. The big rocks kept us from going into the water of a lake that the road runs next to. The passengers in the car were myself and my wife and were not injured but it was a very terrifying incident and the consequences could have been a lot worse. The vehicle has been released to Progressive, the Insurance Company.