When it comes to the safety of your vehicle, brakes are one of the most important things you need to maintain. If you are hearing grinding or squealing noises when you press your brake pedal it is important to get them looked at. There could be something wrong with them that would increase your braking distance and reduce the safety of your vehicle.
The brakes on your car are wear items and will need to be replaced or serviced as time passes. Brakes can be either of the disc or drum type. If they are disc brakes then they have calipers which use pads to grab the brake rotor and slow you down. If they are drum then the brake shoes are pushed on the inside of the drum to bring you to a stop. As the pads and shoes wear away they need to be replaced and the rotors which wear down need to be replaced frequently too.