<p>A mobile telephone station is installed in each of a real society and a virtual society arranged on the Internet. A telephone number of a real mobile telephone is correlated with a telephone number of a virtual mobile telephone owned by a virtual person corresponding to the owner of the real mobile telephone or the same telephone number is assigned to the telephones so as to link their exchange functions. Thus, it is possible to make a telephone call and use a virtual transaction card issued by a virtual transaction company without performing a special operation such as changeover between the telephones for the real society and the virtual society. This realizes a rich and smooth economic activity in the virtual society.</p>
