PURPOSE: To collectively control picture information of a product as to plural personal computers and also to shorten the time for processing the procedure of sales in a sales system where information of the product is displayed in the personal computers.

CONSTITUTION: A color picture information 1-5 is controlled in a central processing unit 1 as catalog information by using high-speed digital lines 1-3 and the color picture requested by an end user is transmitted to the personal computers 1-2 so as to be displayed. Sales activity is executed based on the displayed picture even if there is no product in a store front. Thus, the purchase of the product is decided while retrieving the color picture. The sales of the product is executed when there is a place for arranging a terminal.