What data is stored on a payment card's magnetic stripe?

A magnetic card is a rectangular object that contains sometimes a magnetic strip on the outside or even a magnetic object inside card which contains data. A magnetic card may contain information about somebody such as available credit or pass codes for entering secure buildings. The image is one particular Magnetic card being swiped through a magnetic card reader.
A magnetic stripe card is a type of card capable of storing data by modifying the magnetism of tiny iron-based magnetic particles on a band of magnetic material on the card. The magnetic stripe, sometimes called swipe card or magstripe, is read by swiping past a magnetic reading head. Magnetic stripe cards are commonly used in credit cards, identity cards, and transportation tickets. They may also contain an RFID tag, a transponder device and/or a microchip mostly used for business premises access control or electronic payment.

Magnetic recording on steel tape and wire was invented during World War II for recording audio. In the 1950s, magnetic recording of digital computer data on plastic tape coated with iron oxide was invented. In 1960 IBM used the magnetic tape idea to develop a reliable way of securing magnetic stripes to plastic cards,[1] under a contract with the US government for a security system. A number of International Organization for Standardization standards, ISO/IEC 7810, ISO/IEC 7811, ISO/IEC 7812, ISO/IEC 7813, ISO 8583, and ISO/IEC 4909, now define the physical properties of the card, including size, flexibility, location of the magstripe, magnetic characteristics, and data formats. They also provide the standards for financial cards, including the allocation of card number ranges to different card issuing institutions.
Magnetic stripes on payment cards--sometimes called "magstripes" for short--are divided into three tracks of data which are encoded directly to the magstripe. Only Track 1 and Track 2 are actively used in payment card processing. Track 3 is rarely used and may not always be present on a card.

A magnetic card is a type of card capable of storing data by modifying the magnetism of tiny iron-based magnetic particles on a range of magnetic material for the card. The magnetic stripe, sometimes called swipe card or magstripe, is read by swiping past a magnetic reading head. Magnetic stripe cards are commonly found in credit cards, identity cards, and transportation tickets. They could also contain an RFID tag, a transponder tool andAndor perhaps a microchip mostly used for business premises access control or electronic payment.

Both Track 1 and Track 2 contain enough basic information for processing payment card swipes. Most card readers will be able to read both Track 1 and Track 2 data, in magnetic card case one of the tracks has become unreadable.

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