Oversteer and understeer describe how a car deviates from the driver's intended steering angle while turning. Both happen due to loss of traction, but for different reasons. They are typically used to talk about how a car handles corners on the race track.

Understeer occurs when a car has trouble turning a corner when a driver turns the car. Most common in front-wheel drive vehicles, it's caused by the front wheels losing traction. Instead of travelling along the appropriate cornering line, understeer will send you too far towards the outside of the curve. Turning the steering wheel harshly, abruptly, or too much speed for the available grip will cause the nose of the car to slide wide.

Oversteer occurs when a car turns more than intended while cornering. As a result, the car fails to stay on the appropriate cornering line as the rear end rotates around in an oversteer situation. Often called "fishtailing", this lack of traction means the car becomes unbalanced and much more difficult to control. When this happens, the driver needs to react quickly, with opposite lock to prevent the car from spinning.

The key to saving yourself from either situation is to gradually back off the throttle, straighten out, or turn into the skid if you're oversteering. Gentle, deliberate movements will be the surest way to regain control of your car, regardless of which way you're sliding.