A SWIFT code - also known as a BIC - is made up of 8 characters and is used to identify a particular bank.
An IBAN stands for International Bank Account Number and helps banks identify your specific account for payments. IBANs are not used in all countries. If you are requesting a withdrawal to a bank account which does not have an IBAN, you may put your account number in the IBAN field and your branch code in the Comments field on the withdrawal page.
Your SWIFT code and IBAN can usually be found on your bank statement or online banking.