Computer Modems

A Modem is a device that modulates a carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data. The most familiar example of a modem turns the digital ‘1s and 0s’ of a personal computer into sounds that can be transmitted over the telephone line of Plain Old Telephone System, and once received on the other side, converts those sounds back into 1s and 0s.