The Coin and the Promise (Part 4):

The ability of a customer to obtain goods or services before payment, based on the trust that payment will be made in the future.

The charge for the privilege of borrowing money, typically expressed as an annual percentage rate. The concept originated in ancient Mesopotamia with agricultural loans.

A historical region of Western Asia situated within the Tigris–Euphrates river system. It is where the earliest forms of writing, agriculture, and lending are believed to have originated.

An amount of money borrowed by one party from another.

An early form of insurance/loan contract in which a lender would finance a merchant's sea voyage. The ship was the collateral, and the debt was canceled if the ship was lost.

The management of large amounts of money, especially by governments or large companies. At its core, it is the process of moving value through time.

• Davies, Glyn. A History of Money: From Ancient Times to the Present Day.
• Weatherford, Jack. The History of Money.
• Cohen, Edward E. Athenian Economy and Society: A Banking Perspective.
• Graeber, David. Debt: The First 5,000 Years. (For Mesopotamian interest).
• World History Encyclopedia. "Trade in Ancient Greece."