The RFId allows you to uniquely and universally identify an object without the need to work by direct and visual contact, normally used in tracking systems through some types of barcode or product code.
TAG is a fundamental element, a chip that associates an object to an ID, detected by an aerial that transmits the information contained in the chip to a reader (reader). The reader not only detects the presence of the object in a place, but also re-elaborates the information on the object itself that the chip contains, making it usable through a software for their regular management.