Air in the brake system can make your brake pedal feel spongy and vague. You should flush the fluid every two or three years, which is a relatively easy two-person project.

Upgraded pads for normal driving will likely be noisier, produce more dust, and possibly respond with a harder pedal feel ... change only the front or rear brakes at one time, so a concurrent ...

wherein the brake pedal or the brake lever operates both rear and front brakes simultaneously. But since this is more the exception rather than the rule, this article on braking will focus solely ...