1. A method of displaying goods for sale in an on-line shopping mall, the method comprising: submitting an input of a user to an on-line shopping mall; submitting a desired product category to the on-line shopping mall; receiving data for displaying a prioritized list of goods that are belonging to the desired product category and that are popular to a group of shoppers of the on-line shopping mall to which the user belongs, wherein the prioritized list is formed in response to the user's submission of the desired product category; and displaying on a screen the prioritized list of goods, wherein more popular goods are located above or before less popular goods on the screen.