WHILE TRAVELLING AROUND 20 TO 25 MPH IN THE LEFT HAND LANE OR A TWO LANE CITY STREET, THE CAR IN FRONT OF ME STOPPED TO MAKE A LEFT HAND TURN. I HAD PLENTY OF TIME TO STOP, HOWEVER, WHEN I DEPRESSED THE BRAKE PEDAL, THERE WAS NO RESISTANCE AND THE BRAKE PEDAL WENT DOWN TO THE FLOOR. I QUICKLY RELEASED AND DEPRESSED THE BRAKE PEDAL AGAIN WITH THE SAME RESULT. I TRIED TO AVOID THE VEHICLE BY TURNING TO MY RIGHT, BUT I WAS TOO CLOSE AND HIT THE RIGHT BACK BUMPER OF THE VEHICLE IN FRONT OF ME, CAUSING EXTREME DAMAGE TO THE FRONT LEFT SIDE OF MY CAR. THE INSURANCE COMPANY TOTALLED THE CAR.