What is RFID?

RFID stands for Radio-Frequency Identification.

RFID is a scanning antenna with a transceiver and a transponder.

The short form refers to small electronic devices that consist of a small chip and an antenna. The chip on average is capable of carrying 2,000 bytes of data or less.
The RFID device has the same purpose as a magnetic strip on the back of a credit card or ATM card or a bar code; it provides a unique identifier for that object/person. And, just as a bar code or magnetic strip must be scanned to get the information, the RFID device must be scanned to recover the identifying information.

The common problem with RFID is that the reader collision occurs when the signals from two or more readers overlap.

RFID technology has been available for more than fifty years, but is in use more today than it was five decades ago.

Some differences between RFID and Barcode are:
· RFID are more expensive than barcodes.
· RFID tags have read/write capability (Oyster Card), whereas information cannot be added on barcodes.
· RFID tags can be read at much greater distance than barcodes.
· RFID tags work faster than Barcodes.

Thinking about the technology being secure would be the next question and the answer to that is No. The invasion to an RFID only requires an appropriately equipped scanner.
I guess this is where chip and pin comes in. The only way to keep the chip and data safe is to add a pin/ password to it.

RFIDs have many uses, such as animal/human tracking, credit-cards, keeping track of heavy duty containers and many more.

RFID inside a living body (animal/human).

People have been implanting RFIDs inside them for various reasons. The chips are cased in such a way that they don’t react or irritate but moves around under the skin. The size of the RFID chip which is inserted into the body is usually the size and diameter of a grain of rice, which is inserted with a hyperdermic-type needle.

RFID basic information: http://www.technovelgy.com/ct/Technology-Article.asp?ArtNum=2

Referred Book
M++ by WJ Mitchell 200 MIT