Originally Posted by JARblue

Just so everyone is on the same page...

"Warped" is a term often used incorrectly to describe a rotor with excess pad deposit. This makes the surface of the rotor uneven, which is what causes the vibration. The scenario Boob gives of sitting on the brakes at a stop light after hard braking is excess pad deposit. The pad material basically continues to melt onto the hot rotor in one spot while you're stopped, and then you're left with a uneven portion of the rotor that can be extremely noticeable under braking.

Truly warped rotors are pretty much exclusive to track driving, although I'm sure there's some idiot that managed it on the street. But I think you'd have to be driving like a maniac to do that on the street...