Radio Frequency Identification (RFID) is an emerging technology quickly gaining public acceptance. RFID tags have been used in applications such as gas-pump payment, automated toll collection, baggage tracking, and garment tagging.

An RFID tag is a small chip implanted in a physical object that can be sensed without contact. Each tag has a unique serial number and can contain other programmable information. The information contained in a tag can be transmitted to a reader. In most cases, the reader radiates a low power RF signal to the tag, causing the tag to respond with its serial number. Because the RF signal powers the tag, no batteries are necessary – the tag never wears out. 

Since RFID tags can be read without contact, they can be imbedded in a variety of different form factors. Manufacturers can create tagged credit cards, key tags, watches, and more.

More in-depth information regarding RFID can be found on the AIM website.

AIM is a trade organization for the Automatic Identification and Data Capture industry. Their site also has relevant sections on:

What Is RFID?

An RFID Basic Primer

Glossary of RFID Terms