A "One Cancels the Other" (OCO) order consists of a pair of orders that are created concurrently, but it is only possible for one of them to be executed. This means that as soon as one of the orders is fully or partially filled, the other is canceled automatically. Although less common, OCO orders may also be referred to as Order Cancels Order.
In essence, an OCO is a conditional order that combines a limit order with a stop-limit order, making it a basic form of trade automation. To simplify: an OCO order gives you the option to place two limit orders simultaneously. This makes the OCO function a great trading tool for improving success rates (profit taking) and minimizing potential losses (stop-loss).
OCO orders may also be useful when trying to enter positions. For example, if BNB is trading between $35 and $40, you may create an OCO order that either buys on a resistance breakout (above $40) or buys if the price drops to the $35 support level.
In summary, an OCO order allows you to trade more securely, either by locking potential profits or limiting risks. It also provides more versatility as you can enter or exit positions without choosing between a bullish or bearish bias.