What are government-issued IOUs known as?

Government-issued IOUs are referred to as government securities. These are financial instruments that represent a loan made by an investor to a borrower (in this case, the government). When the government needs to raise funds for various purposes, such as funding public projects, covering budget deficits, or managing national debt, it issues securities to the public.

Government securities come in various forms, including treasury bills, notes, and bonds, depending on their maturity and interest payment structure. While treasury bills are a specific type of government security that matures in the short term, the term "government securities" encompasses all such instruments issued by government entities.

Understanding this classification is crucial for distinguishing between the different types of financial instruments and their characteristics in the broader context of investing and financing public expenditures.