Contactless smart cards are a very different technology from RFID tags. Both are wireless, meaning they can communicate using radio like a cell phone, but contactless smart cards are far more advanced and secure.
Contactless smart cards have small but sophisticated computers inside them. They deliver the highest levels of computer security to protect your identity, privacy or financial information. Contactless smart card technology is suitable for uses such as identity credentials, passports and payment cards.
RFID (Radio Frequency IDentification) tags and labels are used mostly in manufacturing, shipping and object-related tracking. They have minimal built-in support for security and privacy. WalMart and others have been working to use RFID tags to replace bar codes on store-bought items to scan purchases and track inventory, for example.
Another important difference is how far away someone can read the cards or tags. Contactless smart card technology has a very limited read range of four inches or less to prevent tracking or eavesdropping. You can read RFID tags from much further away, however, up to thirty feet. This RFID feature lets you find items in a warehouse or identify railcars as they pass by, typical uses of RFID.