Insurance policy terms and definitions may vary due to state laws and individual insurance companies' guidelines however in general the definition of collision insurance is a physical damage coverage that covers your vehicle if it hits or is hit by another vehicle or object.
Collision automobile insurance is a type of physical damage coverage that is optional. When you purchase this type of policy it covers damage to your car when your vehicle hits, or is hit by, another vehicle or object or if your vehicle is in a roll-over accident. This type of car insurance coverage will pay for damage to your auto regardless of who causes the accident.
Physical damage coverages consist of collision and comprehensive coverage. Generally, collision insurance covers damage to your automobile caused by collision with another object or by upset. Comprehensive insurance covers damage to your automobile from vandalism, theft or glass breakage. Most lien holders require physical damage coverage if you are financing or leasing your vehicle.
These types of optional car insurance coverages come with deductible amounts, which you choose at the inception of your policy. You can typically lower your premiums for these coverages if you choose a higher deductible amount.