Unique signature RFID vs Digitally encoded RFID
Unique signature chipless RFID
In systems where the tag stores data (RFID), there are two extremes. At one extreme, the interrogatory electronics simply senses something unique about that product such as the random orientation of magnetic fibres in it - a pattern highly unlikely ever to be repeated. For this to be useful, the computers in the system must have had prior notice of what that unique feature relates to such as "It is a toothbrush made by X and shipped to supermarket Y". The unique identity must be transmitted to all locations where the tag may need to be interrogated and matched to stored data about the tag. This is very limiting. We can call it Unique Signature RFID.
Digital data is better
At the other extreme, the tag is capable of storing digital information to agreed rules so, at destination, all the toothbrush details can be retrieved simply by the computer and sensor system working to agreed rules to 'read' the code. The computer system does not have to distribute records of every tag. There can be "check" digits and other techniques for the elimination of errors.