Contactless card provides great security and contains approximately 100 times the data storage of a traditional proximity card. The contactless card uses a technology to pass data between the card and the reader without any physical contact being made. There are no contacts to wear out, no chance of an electric shock coming through the contacts and destroying the integrated circuit.
MIFARE® is a 13.56 MHz contactless technology family of microprocessors developed by Philips. MIFARE is the most common contactless chipset on the market and is used in most applications such as access control, cashless vending, mass transit, and payment systems.

For further information about Mifare Contactless Chip, please visit NXP Semiconductors (found be Philips).