Long 

In trading, Long refers to a position that generates a profit when the market price of an asset increases.

Usually used in a context such as going long or long. When you trade in the foreign exchange market, when you buy or sell currency pairs, “going long” means you are buying the base currency and selling the quote currency.

For example, if you go long EUR / USD, you are buying euros and selling US dollars. go short or short, which means that you take a position that will generate profit when the market price of an asset falls. Going long does not necessarily mean buying an asset. Derivatives allow traders to take a long position in a market without actually buying the underlying asset.