RFID Definition Stands for "Radio-Frequency Identification." RFID is a system used to track objects, people, or animals using tags that respond to radio waves. RFID tags are integrated circuits that include a small antenna. The are typically small enough that they are not easily noticeable and therefore can be placed on many types of objects. Like UPC labels, RFID tags are often used to uniquely identify the object they are attached to. However, unlike UPCs, RFID tags don't need to be sc...