Except memory card, the others are capable of processing data. Contact card is the most commonly used smart card among the four. It can be easily distinguished by the sharp gold plate chip on the card. As for contactless card, the chip is embedded inside the card. Hybrid and combi cards are combined contact-contactless smart cards.
Hybrid card has co-existing chips that operate independently.
In combi card, both chips can communicate between themselves. Interoperability Throughout the history of smart card development, various standards have been established for resolving the interoperability problem. The very first standard was the ISO 7816 smart card standard published in 1987. With this ISO standard, smart cards could communicate by using the same protocol. Different smart card vendors have developed their own proprietary smart card operating systems, APIs and even card readers and device drivers, resulting interoperability problems existed in many levels.