Understeer, or what race car drivers call "push", refers to the tendency of a vehicle to continue in a straight line when the wheels are turned. Most modern, front wheel drive (FWD) cars understeer, since the majority of vehicle weight is carried over the front wheels and the front wheels must drive the car, brake and steer at the same time.
Vehicle engineers consider understeer more "recoverable" than oversteer, since you can see where you are headed and it’s usually not as sudden and violent as oversteer.
So, what do you do when you turn the steering wheel and your car keeps going straight? Do less of whatever you're doing - turn less, brake less, or ease off the gas and the car will eventually regain traction. Don’t forget that understeer takes some room to correct; if you decide to practice this, do it in a wide open field or parking lot with plenty of room around you.