Life insurance is an agreement between an insurance company and a policyholder where the insurer agrees to pay a sum of money (sum assured) upon the death of the insured or at the end of the policy term. There are several types of life insurance plans including term insurance, which provides death coverage for a specified term at low premiums without surrender value; whole life insurance, which provides death benefit coverage for the whole life of the insured; and unit-linked insurance plans, which provide both insurance protection and investment opportunities through units purchased based on premiums paid.