All Forex trades result in the buying of one currency and the selling of another (currency trading), simultaneously.

Buying ("going long") the currency pair implies buying the first, base currency and selling an equivalent amount of the second, quote currency (to pay for the base currency). It is not necessary to own the quote currency prior to selling, as it is sold short. A trader buys a currency pair if he/she believes the base currency will go up relative to the quote currency, or equivalently that the corresponding exchange rate will go up.

Selling ("going short") the currency pair implies selling the first, base currency, and buying the second, quote currency. A trader sells a currency pair if he/she believes the base currency will go down relative to the quote currency, or equivalently, that the quote currency will go up relative to the base currency.

An open trade or position is one in which a trader has either bought or sold one currency pair and has not sold or bought back an adequate amount of that currency pair to effectively close the trade. When a trader has an open trade or position, he/she stands to profit or lose from fluctuations in the price of that currency pair.

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