Thin flexible cards are used to automate the controls for access to goods or services such as mass transit, highway toll systems, car parks, vouchers and stored value.

For these applications, data can be written and/or read by machines using various recording techniques: magnetic stripe, optical character recognition, bar code, etc.

ISO/IEC 15457-2:2007 specifies the magnetic stripe and encoding characteristics of thin flexible cards at two points in the card's life cycle:

• at the point of loading into the card-issuing equipment;
• at the point of issue to the public.