Auto insurance is a contract between a policyholder and an insurance company that provides financial protection in case of accidents, theft, or damage to a vehicle. It typically includes coverage for liability, collision, comprehensive, and various other optional coverages. The cost of auto insurance can vary based on factors like the driver's age, location, driving history, and the type of vehicle. It's important to have auto insurance to comply with legal requirements and protect yourself in case of unexpected events on the road.