What is payable on demand paper and payable on time paper?

A negotiable instrument must either be payable on demand or payment on time. An on-time instrument is payable at a specific time and date. The date must be able to be determined at the time the instrument is issued. It may be payable after an elapsed period of time that is readily ascertainable at the time the promise or order is issued, subject to rights of prepayment, acceleration, and extensions. If the instrument is not clear, but there is evidence of an intent to make it payable at a specific date and time, the note is not negotiable. An instrument is payable on demand if it states as much or it does not state any time of payment.