To provide a bar code using system using a network capable of providing instantaneous and easily usable information.

The information terminal 7 of a selling store 3 reads the bar code 13 of requested information on a printed matter such as a catalog 12 by using a bar code reader 10, and accesses the prescribed home page of a server 8 corresponding to the read URL (a step 21). A prescribed WEB site 18 of the server 8 extracts pertinent information (PDF data 14, voice data 15, picture data 16, video data 17 or the like) on an information data base 9, for example the PDF data 14, and transmits the information to the information terminal 7 (a step 22). The information terminal 7 outputs the information received from the server 8 to a prescribed output medium. For example, the information terminal 7 prints the received PDF data 14 on a printer 11, reads the displayed bar code 13, accesses the home page corresponding to the URL (a step 23), and repeatedly executes the processing.