Q. The device that converts computer output for transmission over telephone lines is called:
Answer: Modem
Notes: The modem is an external device or internal electronic circuitry used to transmit and receive digital data over a communications line normally used for analog signals. A modem attached to a computer converts digital data to an analog signal that it uses to modulate a carrier frequency. This frequency is transmitted over a line, frequently as an audio signal over a telecommunications line, to another modem that converts it back into a copy of the original data.