A currency option, like the ones provided by AvaTrade, is a financial derivative. A derivative is a contract whose price depends on an underlying asset (in this case, the chosen forex pair). A currency option gives you the option (not the obligation) to buy or sell before or on a specified date. There are, in general, call options (you have the right to buy) or put options (you have the right to sell). These derivatives are not recommended to beginners due to the high risks involved unless they practice good risk management.