Abstract: The position-linked chat system makes it possible to carry out a chat using many terminals connected to a server device through the Internet. The server device includes a chat room controller which generates many chat rooms based on a geographical standard, a chat room selector which selects a chat room in which a user of certain terminal is to participate based on information relating to the current position of that terminal, and a voice controller which mixes voices of users transmitted from the terminals of respective users participating in the same chat room.

Abstract: A system according to the present invention has a plurality of client units connected to a server unit 100 via a network, to enable users of the client units to communicate with each other using the client units. The server unit stores product information according to a product that an online shopping site sells. The server unit receives a recommendation request for a first user to recommend the desired product, and notifies a second user about a message that the first user recommends the product to the second user, based on the received recommendation request.