My car's brakes/wheels make a screeching/squeaking sound every time I brake. What is wrong and how do I get it fixed?

One of three things is making that sound. Most probable is the wear indicator described by . The cure is to replace the brake pads (generally an inexpensive and uncomplicated job, but may involve also replacing the calipers). Second most probable is simple "brake squeal". The pads are not securely connected to the calipers, and so tend to vibrate in place under certain conditions. Most brake-pad manufacturers include "anti-squeal plates" along with the brake pads; these plates provide a little spring tension between the caliper and the pad, mostly eliminating the squeal. It may be the case that the last person to do a brake job on that car failed to replace the anti-squeal plates. This is a very cheap fix if you find a shop that happens to have a set of anti-squeal plates that fit your pads. In a pinch, you may be able to do the same job with high-temperature silicone, but I'd recommend the plates. If necessary, one can always buy a set of really cheap brake pads for your car just for the anti-squeal plate that come with them. As a bonus, you have a full set of replacement brake pads onhand for next time. This should be a very inexpensive fix. Third most probable is completely worn-out brake pads, with their friction surfaces completely worn through - wearthrough generally happens sooner on the leading end (clockwise on the left side, counterclockwise on the right side). Again, the cure is to replace the brake pads (and maybe the calipers) but this time you'll probably also need to replace the rotors because very few shops these days ever bother to turn rotors, and replacement aftermarket rotors tend to be less expensive than the labor of turning them). This is the most expensive fix because of the additional parts, but labor is not significantly greater than either of the other two first causes listed above.

It's Brake squealing Possible Reasons:- 1. In this case, the friction material vanishes out and the backing plate is jammed against the rotor and hence it results in a very hard screaming noise. 2. There is no proper fitting between the caliper and the brake pad ,piston and brake rotor. 3. Manufacturing issues also results in squealing. 4.Suspension misalignment. Solutions:- 1.     Putting some copper-based grease on the back of brake pads.  It creates a small pocket of sticky lubrication between the front side  of  the brake pistons and the back side of the brake pads which is  enough to  prevent high frequency squeal.  2. Proper suspension realignment.