An insurance score is a number which reflects someone's insurance risk. The higher the insurance score, the lower the risk, and people who are low risk generally have an easier time getting insurance. High scores also mean that insurance will be cheaper, because the insurance company is gambling that someone with a high insurance score may never make a claim, which means that the insurance company will not need to pay out on the policy.
The process used to arrive at an insurance score is rather nebulous, and the insurance industry has been criticized for being so secretive about it. Several independent agencies such as Fair Isaac compute insurance scores, and insurance companies also use internal systems to score people. This means that someone's score can vary quite widely, depending on the system used, much like a credit score.
Credit scores actually play a role in insurance scoring. Insurance underwriters believe that people with good credit represent less of an insurance risk. While people may find this claim dubious, the fact is that the insurance industry relies heavily on very precise statistical analysis, because the goal of an insurance company is to avoid paying out on policies whenever possible. Therefore, if an insurance company has determined that there is a link between a high credit score and a low insurance risk, chances are high that this is definitely the case.
Insurance history also goes into the insurance score. Making claims on a policy causes the score to drop, and people who have not been insured very long will also have a lower score, because the insurance company does not have enough data about whether or not the person is a risk. The type of insurance can play a role as well; someone insuring a frequently stolen car will find that insurance tends to be higher because of the increased risk, for example, and someone buying home insurance in an area where claims are frequent will also experience a drop in his or her insurance score.
People can ask to see their insurance score, but they should be aware that they may not be told which scoring system was used. There also isn't a complete, detailed list of the factors which influence an insurance score. Someone who has a low score may want to ask an insurance agent if there is anything he or she can do to raise the score; as a general rule, improving one's credit score should also cause an insurance score to rise, since the two are closely linked.