A data terminal of a network is used for printing information retrieved from the network, by use of a printer connectable to or incorporated into the data terminal. Along with the information, ad data selected from among those periodically downloaded and stored in the data terminal is printed on the same recording sheet. The user chooses which side of the recording sheet the ad data is to be printed, on the same side as the information or on the opposite side from the information. The data terminal automatically selects those ad data which relates to the category of the information, or the user may designate categories of the ad data to print with the information. A charge modification data producer of the data terminal produces charge modification data and sends it to a provider of the information, for modifying charge for the provision of the information depending upon the amount of ad data printed with the information.