SWIFT Code stands for (Society for Worldwide Interbank Financial Telecommunication) code. A SWIFT code is also called BIC Code – (Bank Identification Code) which is used to identify banks uniquely throughout the world. A SWIFT code is recognized and approved by the International Standards Organization, or ISO, and represents a particular bank or bank branch. It is especially useful in facilitating international wire transfers.
Those are international banking numbers which are used for international transactions. The SWIFT (or BIC) code contains 8 to 11 alphanumeric characters. For more information, please look up in Wikipedia. The IBAN code (International Bank Account Number) contains maximum 34 alphanumeric characters.