Oversteer and understeer are terms related to vehicle dynamics as well as wheel alignment. A difference in the slip angle between the front and back wheels causes both, with the slip angle defined as the difference between the direction of the car and the direction of the wheel.

Understeer occurs when the driver has less control over the wheel. Front wheel drive cars are more prone to it and results from early accelerating when going into a turn, causing the car to spin as the driver get little response from the steering wheel.

Oversteer is more common  in rear wheel drive vehicles and happens when the car turns more than what the driver commands. It causes the rear of the vehicle to fishtail or slide out and is generally not something to be concerned about unless it occurs in muddy or rainy conditions. Ask Putnam Mazda staff about tips to help avoid both.