Thin flexible cards (TFC), the subject of ISO/IEC 15457, are used to automate the controls for access to goods or services such as mass transit, highway toll systems, car parks, vouchers, stored value, etc.
For these applications, data can be written and/or read by machines using various recording techniques such as magnetic stripe, optical character recognition (OCR), bar code, contactless, etc.
ISO/IEC 15457-1:2008 specifies the physical characteristics of thin flexible cards at two points in the card life cycle:

1. at the point of loading into the card issuing equipment;
   
2. at the point of issue to the public.
   

It takes into consideration both human and machine aspects and states the minimum requirements.
The principal card sizes are identified and the characteristics and dimensions are specified.
Guidance concerning the storage and use of cards under various environmental conditions is given.