Modem

Definition for: modem

A peripheral device that connects computers to each other for sending communications via the telephone lines.

The modem modulates the digital data of computers into analog signals to send over the telephone lines, then demodulates back into digital signals to be read by the computer on the other end; thus the name "modem" for modulator/ demodulator.

A modem usually uses PPP to dial into a remote computer.

Winmodems under Linux

http://www.linmodems.org/