Leverage is investing money with borrowed funds. Unlike a regular trade where you purchase a $10 item with $10, in Forex you can use leverage to buy (or sell) the same value with less funds, for example buy $10 with $1 margin (10:1 leverage). Leverage increases the potential of trading profits, however with increased leverage comes increased risk and therefore you can lose more. Leverage is the ratio between the notional value of a trade and the currency used to open the trade, usually the domestic currency of the account. For example, a European trader will have a base currency of EUR while a US trader will have the base currency of USD. The amount of leverage you use in your trading account determines the margin level you must maintain (otherwise you can get a margin call).