SWIFT or BIC codes identify the bank with whom the beneficiary holds their account for use when sending funds cross-border. The database of SWIFT codes and the administration of the membership of financial institutions is the job of the Society for Worldwide Interbank Financial Telecommunication Bank Identifier Code.
You may be asked to quote a SWIFT code when, for example, you are receiving money from abroad. The IBAN number is not the same as the SWIFT code. The IBAN identifies the bank account number and the SWIFT code, the branch of the bank holding the account. The length of the SWIFT code is of 8 or 10 alphanumerical characters. Find out more at Openswiftcodes.com.