It depends. Most' iuanrsnce companies insure both. Meaning if somebody drives your car (as long as they are not excluded.) They will be covered with the same limits as if you were driving as long as they drive with your permission. Also, if you drive someone else's car, the car's iuanrsnce will be primary, and your iuanrsnce will be secondary. However, some insurers are more strict than others, some will not allow anybody not on the policy to drive. Insurance co's will usually try to find out who lives in your household and is old enough to drive so they can exclude them or add them to your policy. Sometimes, if somebody in your household drives regularly and they are in an accident, the iuanrsnce company might deny the claim because you did not let them know that they were in the household. If somebody outside of your household crashes your car, the ins co will cover the loss and ask that you exlclude the driver so they can no longer drive your car in the future.