what is insurance ?

[1] promise of reimbursement in the case of loss; paid to people or companies so concerned about hazards that they have made prepayments to an insurance company.
policy: written contract or certificate of insurance; "you should have read the small print on your policy"

[2] Insurance is the transferance of risk. you have a risk..ex: you might get sick, you might die, etc. insurance TRANSFERS that risk (or rather the financial hardship created by it) from YOU to the insurance comany for a small monthly premium. So for example you MIGHT get sick and need $300,000 worth of medical services...So knowing you could never afford that, you purchase insurance...transferring the risk to the insurance company in exchange for your monthly premium.

[3]Insurance, in law and economics, is a form of risk management primarily used to hedge against the risk of potential financial loss. Ideally, insurance is defined as the equitable transfer of the risk of a potential loss, from one entity to another, in exchange for a reasonable fee.