SWIFT is a global network of secure messages between banks, used for most international bank transfers. The name is also used for the transfer itself and for the bank identifier code (BIC).
In plain words
SWIFT does not move the money itself. It passes payment instructions to banks (“debit this one, credit that one”) and the funds travel through the banks’ correspondent accounts. That is why intermediary banks with their own fees can appear on the way, and a transfer can take several working days. A bank is identified by its BIC (also called a SWIFT code) of 8 or 11 characters.
Example. A US client pays a Ukrainian sole proprietor in dollars: the client’s bank sends a SWIFT message, the money passes through a correspondent bank and arrives within a few working days, and intermediaries may deduct their fees from the amount.