Why does traction control light illuminate intermittently on my 2010 Ford Edge

Is it supposed to do this when the traction control "kicks in"? - I have a 99 Mustang that alas, did not have the traction control - it was a $400 option and I bought mine slightly used. However, I sold Fords for a brief time, and when leaving the dealership in the Clairemont Mesa area the traction control would light up for a few and the car would simply move efficiently without squealing. On that grade if I pull out with my Mustang you almost always got a bit of slippage from the tires even when trying to accelerate moderately on that grade.