What is a stop loss — and why you should always use one
A stop loss is an instruction that closes your trade automatically if the price moves against you to a level you choose. It limits how much one trade can cost you.
Why always? Markets can move fast. Without a stop loss, one bad trade can take much more than you planned. With one, you decide the worst case before you enter.
A common beginner rule: risk only a small part of your account on any one trade, for example 1 %. With an account of 1,000 (in any currency), that is 10. Your stop loss distance and your trade size are then chosen together so that, if the stop is hit, the loss stays near that amount.
In MetaTrader: the order window has a "Stop Loss" field. You can also add or move it later on an open position. The "Take Profit" field closes the trade at a target in the same way.
A stop loss is not a guarantee: in very fast markets, or over a weekend gap, the closing price can be worse than the level you set. It still protects you far better than having none.
Continue in the course: the Foundation Course — start free, 14 days, no card
Trading involves significant risk of loss. Practise on a demo account first. Holy Trading Science provides education, not financial advice.