Final answer:
Postdated checks are checks with a future date, delaying payment until a specific date. I.O.U. is a written acknowledgment of a debt owed.
Step-by-step explanation:
Postdated checks are checks that have a future date written on them, meaning they cannot be cashed or deposited until that date. These checks are commonly used to delay payment until a specific date, such as an upcoming payday. On the other hand, an I.O.U. (which stands for 'I owe you') is a written statement that acknowledges a debt owed by one party to another. It is a simple way to record a promise to repay a loan or debt.