Magnetic Stripe Card is a type of card that uses magnetic fields to store data and is widely used in a variety of payment and identification scenarios. Here is a detailed explanation of magnetic stripe cards:

Definition and use:
Magnetic stripe cards are a common card technology that is mainly used to store and transfer data. In most cases, when the term "magnetic stripe card" is used, it usually refers to ISO-standard financial exchange cards such as bank cards, credit cards, debit cards, etc.

Structure and track:
The magnetic strip is usually composed of three tracks, namely track 1, track 2 and track 3.
Track 1: Main memory card account number, card issuing line code and other information. Its data format is variable length, typically 79 characters.
Track 2: Main memory card main account number, cardholder name, expiration date and other important information. Its data format is also variable in length, typically 40 characters.
Track 3: Generally not used to store important payment information, additional information can be stored as needed.