BIN - " Bank Identification Number "or"bank identification Number". Used to identify the issuing bank.
These are the first 6 digits of the card number, they are unique and help to identify the bank that issued it during clearing, processing or authorization.
You can also find out the country of issue of the card, the type of card and the payment system. The ISO/IEC 7812-1 format is regulated (according to SWIFT).