A network device comprises a Web service provider unit. In order to provide a client in a network with a service to display a list of multiple images stored in a predetermined storage area, the client having a function as a Web browser, the Web service provider unit sends the client in response to a request from the client a markup language file described in a predetermined markup language. The Web service provider unit includes a layer configuration unit and a Web program generator. The layer configuration unit configures as an element included in the markup language file at least one layer having a visibility attribute that defines whether or not the layer will be displayed on the client and assigns each of the multiple images to one of the layer. The Web program generator generates a Web program that operates on the client and sends the Web program to the client. The Web program is a program that causes the client to implement a first function to set the visibility attribute of the layer and a second function to issue a request to obtain each of the multiple images such that each of the multiple images is respectively placed on the layer to which the image is assigned.