Program data and information associated with at least a consumer commodity
that appears in a program of the program data are synchronously
transmitted. The program data and the information associated therewith
are received. The received program data is reproduced. The reproduced
data is displayed on a displaying portion. Information associated with
one selected from a plurality of consumer commodities displayed on the
displaying portion is extracted and displayed. The viewer can buy a
consumer commodity at a store corresponding to the extracted information.