→ Annuity due ⇒ Annuity due is an annuity whose payment is to be made immediately at the beginning of each period. Payments are made at the beginning of each payment period.
→ Perpetual annuity ⇒ A perpetuity is a security that pays for an infinite amount of time. In finance, perpetuity is a constant stream of identical cash flows with no end. If the payment of annuity continues for an indefinite period.
→ Annuity certain ⇒ An annuity certain is an investment that provides a series of payments for a set period to a person or the person's beneficiary or estate. If the amount of annuity is paid for the definite no. of the period.