Debt memos, also known as CHITS (5 letters) and IOUS (4 letters), are documents that record a debt or loan between two parties. They are legally binding documents that outline the terms of the loan, such as the amount borrowed, the interest rate, and the repayment schedule. Debt memos are typically used in business transactions, but can also be used for personal loans. They provide evidence of the debt and serve as a reminder to the borrower of their obligation to repay the loan.