Most cars use disc brakes.  A hydraulic system filled with brake fluid triggers a set of padded clamps known as calipers, causing them to squeeze together on a disc known as the rotor. The friction that occurs between the pads and rotor eventually stops the car.

 

There are some obvious signs that your brakes need servicing, such as the brake light appearing on your car's dashboard or the feeling that your vehicle is taking longer to stop than it should.

 

One of the warning signs that your brakes need servicing can come from a small indicator in your braking system that emits a high-pitched squeal when your pads need replacing.   In addition to the squeal from the sensor, you'll also want to listen for a harsh grinding sound. This means that you've gone completely through your brake pads and when the metal of the calipers is grinding against the metal of your rotors.  This may cause harm to your rotors and cost more to repair.

 

this could indicate a problem with a stuck If your car wants to make a right- or left-hand turn while driving or braking caliper causing friction on one wheel and not the others, causing your car to pull to the side where the caliper is stuck.  Though this may also be a lower inflated tire, it is a warning sign that your card should be looked at.

 

If your brake pedal pulses under normal braking circumstances, you could have a problem with warped rotors.

 

Rotors usually only warp when they're under extreme stress for an extended period. The friction-generated heat caused by driving down steep mountainsides or by stopping frequently while towing something heavy, for example, can cause the metal of the rotors to change shape.  This same pulse could be the cause of misaligned tires.  Both of these problems can be easily diagnosed by a licensed mechanic.