Radio-Frequency Identification (RFID) device serves the same purpose as a bar code or a magnetic strip on the back of a credit card, it provides a unique identifier for that object. The same as a bar code must be scanned to get the information, the RFID device must be scanned to retrieve the identifying information.
The advantage of RFID devices over the others mentioned above is that the RFID device does not need to be positioned precisely facing the scanner. RFID devices work within a few feet (up to 20 feet for high-frequency devices) of the scanner. Bar code Tags can only be read manually, one at a time. With RFIDs multiple (>100) tags can be read simultaneously. Bar codes are read only, where RFID allow read, write, update and modify. Bar codes are much easier to reproduce or counterfeit, where RFID come with high security features, difficult to replicate. Data can be encrypted, password protected, or include a “kill” feature to remove data permanently. Bar codes cannot be used to trigger events where RFIDs can be used to trigger events like alarms.
One of the reasons that it has taken so long for RFID to come into common use is the lack of industry standards. Most companies invested in RFID technology only use the tags to track their items; many of the benefits of RFID come when items are tracked from company to company or from location to location.