A refrigerator capable of transmitting and receiving information over a network and having an automatic food ordering function and a method for operating the same, wherein the residual amounts of food articles stored in containers of the refrigerator are measured through sensors installed in the containers and then displayed on a screen of a display unit, thereby enabling a user to easily recognize the residual amounts of the food articles stored in the refrigerator without opening the door of the refrigerator. The measured residual amounts of the food articles are compared with minimum proper amounts of the food articles preset by the user, respectively. In the case where the measured residual amount of a specific one of the food articles is smaller than the minimum proper amount of the specific food article, the specific food article is automatically ordered and delivered.