similarly represented as physical quantities within the computer system memories or registers or other such information storage transmission or display devices e ncoding via an a lternating p olarity of a m agnetic f ield in one embodiment of the present disclosure a smart credit card device comprises a dynamic magnetic region strip incorporating a main inductor assembly from which programmed magnetic field data symbols are dynamically generated in one embodiment the inductor assembly may be a planar coil formed within the material that embodies the credit card an advantage of using a planar coil is that it can dynamically produce a magnetic field in such a manner as to emulate the interaction between a traditional magnetic strip and a conventional credit card reader as the magnetic strip of a conventional credit card is passed through a magnetic reader head stripes of alternating magnetic polarity embedded in the strip induce a magnetic field of alternating polarity at the reader head the pattern formed by the alternating polarity of the magnetic field encodes information which when transformed by a transducer to a current signal in the magnetic reader head provides user information for a transaction embodiments of the present disclosure provide a credit card device able to generate a programmed magnetic field wherein data is encoded and represented by an alternating polarity of the generated magnetic field in a similar manner to a conventional plastic credit card the magnetic field produced by the planar coil is able to be read by a pickup or u201c transducer u201d and to thereby transmit information to the magnetic card reader fig1 illustrates a credit card transaction 100 performed between a credit card device 101 and a conventional magnetic reader 150 the credit card device 101 generates a magnetic field of alternating polarity 120.