Currency relative values of the different currencies. Currencies in this sense are defined by governments, and each type has limited boundaries of acceptance. Other definitions of the term "currency" are discussed in their respective synonymous articles banknote, coin, and money. The latter definition, pertaining to the currency systems of nations, is the topic of this article. Currencies can be classified into two monetary systems: fiat money and commodity money, depending on what guarantees the value (the economy at large vs. the government's physical metal reserves). Some currencies are legal tender in certain political jurisdictions. Others are simply traded for their economic
A Monetary History of the United States bank failures and the massive withdrawals of currency from the financial system that followed significantly shrank the money supply (the total amount of currency and outstanding bank deposits), which greatly exacerbated the economic contraction. The book criticizes the Federal Reserve Bank for not keeping the supply of money steady and not acting as lender of last resort, instead allowing commercial banks to fail and allowing the economic depression to deepen. The book's main theme is the "money supply". It tracks this through three numbers: The money supply (cash + deposits) can be computed from these three numbers. The supply shrinks