This invention has been made to manage data possessed by a user on a network. One of this invention is a data management method using a network system which includes a server and a client terminal, including the step of making a control server receive a user's data storage request from the client terminal, the step of making the control server select a data server located in an area that has a predetermined relationship with an area set by the user, and the step of making the control server send data associated with the data storage request to the selected data server, and store the data in the selected data server.
