A Demand Promissory Note (DPN) is a legally binding document that is typically used for secured lending between two parties. It is a written promise from one party (the maker) to pay another party (the payee) a certain amount of money on demand—or at a specified time in the future. A DPN typically includes the amount of money due, the date on which payment is due, and the interest rate to be paid. A Demand Promissory Note can be either unconditional or conditional. An unconditional DPN does not require any action from the maker to trigger a demand for payment. A conditional DPN requires certain conditions to be met before a demand for payment can be made. Types of Demand Promissory Note include: — Unconditional Demand Promissory Not— - Conditional Demand Promissory Note — Secured Demand Promissory Not— - Unsecured Demand Promissory Note — Revolving Demand Promissory Not— - Balloon Demand Promissory Note — Variable Demand Promissory Not— - Demand Line of Credit Promissory Note.