Banks have two important economic functions. First, they operate a payments system, and a modern economy cannot function well without an efficient payments system. We make most of our payments by writing checks, swiping credit cards issued by banks or tied to them, and by paying bills via online banking. Most of the money stock of the country is in fact bank money; the rest of the currency is “legal tender” issued by the government, namely Federal Reserve Notes and coins. We have confidence in bank money because we can exchange it at the bank or an ATM for legal tender. Banks are obligated to hold reserves of legal tender to make these exchanges when we request them.
The second key function of banks is financial intermediation, lending or investing the money we deposit with them or credit they themselves create to business enterprises, households, and governments. This is the business side of banking. Most banks are profit-seeking corporations with stockholders who provide the equity capital needed to start and maintain a banking business. Banks make their profits and cover their expenses by charging borrowers more for loans than they pay depositors for keeping money in the bank. The intermediation function of banks is extremely important because it helped to finance the many generations of entrepreneurs who built the American economy as well as the ordinary businesses that keep it going from year to year. But it is inherently a risky business. Will the borrower pay back the loan with interest? What if the borrower doesn’t repay the loan? What happens to the banking system and the economy if a large number of borrowers can’t or won’t repay their loans? And what happens if, in the pursuit of profit, banks do not maintain levels of reserves and capital consistent with their own stability?