Smart cards are plastic cards with embedded integrated circuits that come in different varieties from simple memory cards to those with microprocessors. There are four main categories of smart cards: unprotected memory cards, wired logic memory cards, microprocessor cards, and contactless cards. The IBM Multifunction Card is a sophisticated smart card solution that supports private and public key cryptography and can host multiple applications. It has a file system similar to a computer hard drive and supports commands for security functions, application data, and card management. Standardization plays a key role in smart card acceptance and is driven by organizations like ISO and the smart card industry.