The first currency stated in a currency pair
In the notation EUR/USD, EUR is the base currency. USD is the counter currency. This does NOT represent the number of euros for 1 US dollar like in a division. In fact it is the opposite and represents the number of US dollars to a euro.
When a trader longs, or buys the EUR/USD, he is buying the base currency (EUR) while selling the counter currency (USD). On the flip side, shorting or selling the EUR/USD would be selling the base currency (EUR) while buying the (USD).









