This note descries what Eurodollar markets are and how have they developed. Euromarkets emerged historically in Europe or specially in London, and deal in currencies another than U.S. dollars. Eurodollars are dollar deposits loans made or granted outside the United States; and, an organization or place where Eurodollars are transacted between buyers and sellers is called the Eurodollar market. It emerged in London because (a) London has accumulated financial wisdom and technical skills in the great merchant banks; (b) it has imposed restrictions on offshore transactions; and (c) it is located in the centre of the globe.