Car insurance policy requirements differ by state!
In order to have insurance you have to have an insurable interest, therefore you do not have to get insurance when you're driving your friends car because your friend as insurable interest and they are the ones that have the insurance on the car.
Rule of thumb is a borrow a car borrow the insurance.
Many people don't know that you can self insurance in many states if you meet the financial requirements and get the appropriate state required paperwork, but many choose to just get an insurance policy from an insurance company. It is easier, and takes away some of the risk...but it does come at a cost and wealthily individuals may want to consider it they have several car or want to be SELF INSURED.
how do I qualify for car insurance
how do I qualify for car insurance is easy just call 1-540-CAR-SAVE