Over the years, car braking systems have evolved from drum brakes toward the use of disc brakes. You will occasionally still see drum brakes being used on the rear of a low-end car, but discs are definitely the majority — and for good reason. Disc brakes never need adjusting, and the braking power usually isn’t too adversely affected if they get wet. Drums are supposed to self adjust, but sometimes they don’t, and if on the front, can spin you out if one side is adjusted and the other is not, although on the rear, not so much. If you...