Abstract: A public terminal links to an analog telephone network (STN) and to a digital network (ISDN), and includes a central unit (12) furnished with peripherals (14, 16, 18) providing a human/machine interface, an algorithm for navigating around the computer network, and a telecommunications payment card reader (22) that is linked to telephony circuits for establishing a telephone link with a server center as a function of available credit and for maintaining the telephone link. The terminal is linked to the digital network by a relay (38) controlled by the central unit (12) in such a way as to establish a communication between the central unit and the digital network so long as the analog telephone link with the server center is maintained.