This material may not seem relevant to currencies today, but even modest perspective understand the appearance of a subject relate to each other and the whole. "He who knows only his own generation remains always a child." - George Norlin
Foreign exchange is the simultaneous buying of one currency and selling another. Currencies are traded through brokers and dealer and are executed in currency pairs; for an example, Euro dollar and U.S. dollar (EUR/USD) or the British pound and the Japanese yen (GBP/JPY).