Abstract: In accordance with an adaptive dialing method, a dialer control module controls a modem to place a telephone call to a telephone line and efficiently classify the telephone line, that is, to determine whether a device connected to the telephone line is one or more of a plurality of types of devices, illustratively, a voice telephone, a fax machine or modem, or a data modem. In accordance with the method, the dialer control module can enable the modem to, in one call, determine whether the telephone line is connected to a voice telephone, on the one hand, or a fax machine or modem or a data modem, on the other hand.