ESP is Electronic Stability Control.
Basically, if you go in to a corner a bit too fast and the car starts to move off line, the ESP will apply the brakes on individual wheels to bring it back under control.
Pushing the button will switch the ESP off.
If the ESP light is on it means the ESP is off.
ESP is an emergency "save your a**e" measure, and is not intended as a substitute for good driving.
gully, December 2009
