When insured parties experience a loss for a specified peril, the coverage entitles the policyholder to make a 'claim' against the insurer for the covered amount of loss as specified by the policy. The fee paid by the insured to the insurer for assuming the risk is called the 'premium'. Insurance premiums from many insureds are used to fund accounts reserved for later payment of claims—in theory for a relatively few claimants—and for overhead costs. So long as an insurer maintains adequate funds set aside for anticipated losses (i.e., reserves), the remaining margin is an insurer's profit.

Reference: www.wikipedia.org