Can be very tiny, about the size of a rice grain, or several square inches, depending on the amount of information they need to contain and the environment in which they are used.

Radio Frequency Identification tags

Explanation:

RFID tags (Radio Frequency Identification tags) are type of the tracking system that uses smart barcodes so to identify items.  

The tags utilize the radio frequency technology. The radio waves from the tag transmit data to the reader which then transmit the information to the Radio Frequency Identification computer system.  

These tags are used frequently for the merchandise. They are also used to track the pets, vehicles and even the patients which are suffering with Alzheimer’s disease.  

The size of the tag depend on the environment and the amount of the information that to be transmit.

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