An insurance premium is the amount paid by a policyholder to an insurance company in exchange for coverage. Premiums are determined by insurance companies based on statistics and calculations regarding mortality rates, expenses, and expected investment returns. Premiums can be paid as a single payment or in installments, and the amount may differ between companies. Net premium only considers mortality and interest, while gross premium also includes expenses and profit loading. Calculating net single premium involves determining present values of future claims based on the mortality table, sum assured, interest rate, and number of insured individuals.