Provided is means for obtaining required data, despite there being only one kind of reading device or one kind of reading method for a plurality of item types. The present invention comprises: means for reading a barcode and a change-in-environment part; means for extracting, from the barcode which has been read, data pertaining to the change-in-environment part; and means for recognizing change-in-environment data on the basis of the data pertaining to the change-in-environment part. Further, an item has a change-in-environment part and a barcode which contains the data relating to the change-in-environment part.