squeeking can also be caused by crystalization... in other words.. you're braking really lightly, generating massive amounts of heat, and the pads are cooling too quickly causing crystalization...those rubbing against the rotors will cause squeeking... if this is the case...
from a good speed.. saaaaaayyy 100 mph..
.. just kidding.. like 40 mph should be good.. step on the brakes HARD! just like some kid runs infront of your car.. slam on the brakes, but don't lose traction..
ideally, to prevent this.. you should be braking late and hard (not as hard as above.. i guess kind of like when you think you can make the red light but decide not to at the last second.. a little bit less than that..).. this prevents heat build up and protects your rotors from warping, however, you will go through brake pads faster... but it's not practical to drive like this on the street.. mainly because of other drivers and vehicles (not all brakes are created equal.. and definitely not all drivers).. you drive like that and you'll be having someone slam into your rear in a weeks time..