For some markets, we will request your IBAN number rather than your standard account information in order to process payments. Your IBAN number is simply an international version of your standard bank account number.
You can normally retrieve your IBAN from your online banking facilities or on your bank statements. Alternatively, you can contact your bank directly to get ahold of your IBAN number.
Some banks also have IBAN calculators, where you input your standard bank account information in return for your IBAN number - just have a look for it on their website or by doing a quick online search.