On the other hand, radio frequency identification (RFID) tags are much cheaper and disposable. Like supermarket bar code tags, these RFID tags can be printed in rolls of individual stickers. However, not all babies cry when the diaper is wet and this exposes the passive ones to painful rashes later on. In order to function, RFID tags receive energy in the form of radio waves emitted by an RFID reader. This enables products with RFID tags to be identified and tracked.

Source: Daily Nation February 27, 2020 12:56 UTC