A debit order is a commitment you make to make a payment every month from your bank account to another person or entity. The amount that you agree to pay is taken from your bank account for a service or to repay a loan on a date that you decide on. Debit orders make it easy to keep track of payments and ensure they go off every month. You can also request a payment history in terms of debit orders to know exactly what is going in-and-out of your account.
Because you decide on the date your debit order will go off, you can decide which of your financial priorities get paid first.