Are special agents or companies doing business as brokers? Buying and selling currencies called Forex brokers. They link between currency buyers and Forex brokers. Earnings are derived from spreads (fees or spreads) that appear between prices. Offers and interest rates in double currency. For example, brokers can spend US $ 1.5475 to buy euros and sell them for US $ 1.5478. The brokerage receives $ 0.0003 in each currency sold.