Conditional Orders allow you to link orders together under a certain tag.
The One Cancels the Others (OCO) order is a specific kind of conditional order. This order takes a specific tag, called an OCO ID. When an order with a specific OCO ID is filled, all other orders with the same OCO ID are cancelled.
OCO orders allow you to form complex relationships between orders, making certain orders dependent on other orders.
To make an order an OCO order, you must fill out the OCO ID in the order submission settings.