Insurance is some thing for risk management mainly used for managing risk and for contingent loss.Now comming to the point insurance rate is the thing used to get the amont called as premium amount that should be charged for actually applying for insurance.
Now there are certain rules that share characteristics to apply for insurance.

ONE:A LARGE NUMBER OF HOMOGENEOUS EXPOSURE UNITS:
This is for individual members of very large classes like automobiles insurance and is covers lot for countries like united states and london and many more.

TWO:DEFINITE LOSS:
This means that there should be loss that is subjected to insurance,and it should follow the properties of insurance.these types include death of a individual under sertain conditions not all deaths are allowed like susides and all.

THREE:ACCEDENTAL LOSS:
The accidental loss in which the clame should fortuitous , or it should be off your control to clame the insurance this should also cover the loss that is caused and alsoneed to adjust the things and supply the capital needed to cover the costs.and the costs depend on the types of loss that is going to occur

FOUR:LARGE LOSS:As you can see from the heading itself this insurance relies to those who are or may be expecting major losses.hear insurance premium needs to needs to cover the expected cause of losses and supply the capital needed for the insurance.

FIVE: AFFORDABLE PREMIUM:
This comes into existance when the likeleness of an event that is insured is so high or the cost of the event is huge then the relative premium is also huge.It is not likely that any one will buy insurance.

SIX:CALCULATBLE LOSS:There are few elements that are or can be estimated by one that must be at least estimable,if cannot be foramlly calulable the propability of loss and the attendant cost.This can be estimated by any body.Hear a proof of loss associated with the clame presented under the policy.

SEVEN:LIMITED RISK OF CATASTROPHICICALLY LARGE LOSSES:
hear in this case risk level is oftedn aggregate and the same type of loss can happen to many individuals in the field and the ability of the insurers becomes constrained,not by the factors surrounding the individuals,but the factors holding the sum of the polacy holders.
now comming to the types of insurance.
TYPES OF INSURANCE: