POLi is a payment gateway built by Australia Post. Most banks are supported but you will need to have internet banking setup. POLi only works online and cant be used in person at an Australia Post outlet.
If you select POLi as a payment method it will ask you to select your bank and then enter in your banking username and password. There is no need to be concerned, POLI will confirm the amount you want to transfer and upon approving will set up a secure link between our banks.
POLI sends us a receipt to confirm that the money has been sent from your bank and upon receiving this we automatically credit your account.