Commercial or retail banks are businesses that trade in money. They receive and hold deposits, pay money according to customers' instructions, lend money, offer investment advice, exchange foreign currencies, and so on. They make a profit from the difference (known as a spread or a margin) between the interest rates they pay to lenders or depositors and those they charge to borrowers. Banks also create credit, because the money they lend, from their deposits, is generally spent (either on goods or services, or to settle debts), and in this way transferred to another bank account - often by way of a bank transfer or a cheque (check) rather than the use of notes or coins - from where it can be lent to another borrower, and so on. When lending money, bankers have to find a balance between yield and risk, and between liquidity and different maturities.
Investment banks, often called merchant banks in Britain, raise funds for industry on the various financial markets, finance international trade, issue and underwrite securities, deal with takeovers and mergers, and issue government bonds. They also generally offer stockbroking and portfolio management services to rich corporate and individual clients. Investment banks make their profits from the fees and commissions they charge for their services.
In some European countries (notably Germany, Switzerland and Austria) there have always been universal banks combining deposit and loan banking with share and bond dealing and investment services, but for much of the 20th century, American legislation enforced a strict separation between commercial and investment banks. The Glass-Steagall Act, passed during the Depression in 1934, prevented commercial banks from underwriting securities. This act was repealed in 1999. The Japanese equivalent was abolished the previous year, and the banking industry in Britain was also deregulated in the 1990s, and financial conglomerates now combine the services previously offered by banks, stockbrokers, and insurance companies.
A country's minimum interest rate is usually fixed by the central bank. This is the discount rate, at which the central bank makes secured loans to commercial banks. Banks lend to blue chip borrowers (very safe large companies) at the base rate or the prime rate; all other borrowers pay more, depending on their credit standing (or credit rating, or creditworthiness): the lender's estimation of their present and future solvency. Borrowers can usually get a lower interest rate if the loan is secured or guaranteed by some kind of asset, known as collateral.
In most financial centres, there are also branches of lots of foreign banks, largely doing Eurocurrency business. A Eurocurrency is any currency held outside its country of origin. The first significant Eurocurrency market was for US dollars in Europe, but the name is now used for foreign currencies held anywhere in the world (e.g. yen in the US, euros in Japan). Since the US dollar is the world’s most important trading currency – and because the US for many years had a huge trade deficit - there is a market o many billions of Eurodollars, including the oil-exporting countries' 'petrodollars' Although a central bank can determine the minimum lending rate for its national currency it has no control over foreign currencies. Furthermore, banks are not obliged to deposit any of their Eurocurrency assets at 0% interest with the central bank, which means that they can usually offer better rates to borrowers and depositors than in the home country.