Three tracks can be stored on the magnetic stripe of a bank card. Two tracks are most commonly used: track1 and track2.
The third track track3 has no practical application at the moment. The track1 and track2 formats are defined by ISO/IEC 7813, and the track3 format is defined by ISO/IEC 4909. The data lengths in the three tracks are limited. So, the first track can contain no more than 79 alphanumeric characters, the second track – no more than 40 and the third – no more than 107. The second track contains the name of the cardholder in Latin transcription, which, if the acquirer wishes, can be printed on the receipt of the device, which often causes mixed feelings in the cardholder from surprise to delight. The data of the first and second tracks can only be read from the magnetic strip, while the data of the third track can not only be read, but also overwritten by the device on which the operation is performed. For example, track3 allows you to overwrite the limits set on the card, the number of attempts of incorrectly entered PIN codes, the date of the last operation performed. The contents of the tracks are confidential information. If the contents of the tracks get into the hands of unauthorized persons, the map must be reissued without fail. A particular vulnera
