ESC stands for “electronic stability control”, which is a system in your car designed to keep your steering on course. These systems use computers to control the braking of specific wheels to help you maintain control of your car in dicey situations, like spinning out due to slipping wheels.
ESC is intended to make it harder for your car to flip over—but it won’t apply hard braking or steer your vehicle automatically. It helps prevent oversteering and understeering as well, like in the event of a hydroplane or poorly-judged turn.
ESC is activated when you start your car and monitors your steering and speed sensors in the background while you drive, automatically engaging when necessary.