Large number of similar exposure units: Since insurance operates through pooling resources, the majority of insurance policies are provided for individual members of large classes, allowing insurers to benefit from the law of large numbers in which predicted losses are similar to the actual losses. Exceptions include Lloyd's of London, which is famous for ensuring the life or health of actors, sports figures, and other famous individuals. However, all exposures will have particular differences, which may lead to different premium rates.
^ Berger, Allen N.; Cummins, J. David; Weiss, Mary A. (October 1997). "The Coexistence of Multiple Distribution Systems for Financial Services: The Case of Property-Liability Insurance" (PDF). Journal of Business. 70 (4): 515–46. doi:10.1086/209730. Archived from the original (PDF) on 2000-09-19. (online draft Archived 2010-06-22 at the Wayback Machine)
Any risk that can be quantified can potentially be insured. Specific kinds of risk that may give rise to claims are known as perils. An insurance policy will set out in detail which perils are covered by the policy and which are not. Below are non-exhaustive lists of the many different types of insurance that exist. A single policy that may cover risks in one or more of the categories set out below. For example, vehicle insurance would typically cover both the property risk (theft or damage to the vehicle) and the liability risk (legal claims arising from an accident). A home insurance policy in the United States typically includes coverage for damage to the home and the owner's belongings, certain legal claims against the owner, and even a small amount of coverage for medical expenses of guests who are injured on the owner's property.
Methods for transferring or distributing risk were practiced by Chinese and Babylonian traders as long ago as the 3rd and 2nd millennia BC, respectively. Chinese merchants travelling treacherous river rapids would redistribute their wares across many vessels to limit the loss due to any single vessel's capsizing. The Babylonians developed a system which was recorded in the famous Code of Hammurabi, c. 1750 BC, and practiced by early Mediterranean sailing merchants. If a merchant received a loan to fund his shipment, he would pay the lender an additional sum in exchange for the lender's guarantee to cancel the loan should the shipment be stolen, or lost at sea.
Cash in on major life changes. Certain life events could translate to cheaper car insurance, so shop for quotes whenever something major changes in your life. For instance, many companies offer a lower rate for married couples or domestic partners. Or perhaps you moved to a suburb with lower accident and crime rates. If your risk for accidents goes down, your rates just might, too.