Leverage lets you control a large EUR/AUD position with a relatively small deposit, called margin. For example, with leverage you might open a EUR/AUD position many times larger than the cash you put up. This amplifies your exposure to the Forex market — and it is the single most important concept to understand before trading EUR/AUD, because it cuts both ways.
Margin is the portion of your account set aside to keep a EUR/AUD position open. If the market moves against you and your account equity falls too far, you may receive a margin call or have positions automatically closed to prevent further loss. The higher the leverage on EUR/AUD, the smaller the adverse move needed to trigger this, which is why experienced traders often use far less leverage than the maximum available.
Used responsibly, leverage is a tool for capital efficiency, not a way to take outsized bets. The disciplined approach is to size each EUR/AUD position by the risk you are willing to lose — not by the leverage you can access. Keep plenty of free margin, set stop-losses on every EUR/AUD trade, and treat high leverage with the caution it deserves.