SWIFT code also known as SWIFT-BIC, BIC code, SWIFT ID ( ISO 9362 ) is a standard format of Business Identifier Codes approved by the International Organization for Standardization (ISO). It is a unique identification code for both financial and non-financial institutions. (When assigned to a non-financial institution, a code may also be known as a Business Entity Identifier or BEI.) These codes are used when transferring money between banks, particularly for international wire transfers, and also for the exchange of other messages between banks. The codes can sometimes be found on account statements.
The overlapping issue between ISO 9362 and ISO 13616 is discussed in the article International Bank Account Number (also called IBAN). The SWIFT network does not require a specific format for the transaction so the identification of accounts and transaction types is left to agreements of the transaction partners. In the process of the Single Euro Payments Area the European central banks have agreed on a common format based on IBAN and BIC including an XML-based transmission format for standardized transactions; the TARGET2 is a joint gross clearing system in the European Union that does not require the SWIFT network for transmission (see EBICS). The TARGET-directory lists all the BICs of the banks that are attached to the TARGET2-network being a subset of the SWIFT-directory of BICs
source : http://en.wikipedia.org/wiki/ISO_9362