What is the use of MODEM

MODEM is a device used for modulation and demodulation(Modulator-Demodulator). Conversion of digital signals into telephone signals (analog signals) is called modulation. Converting telephone signals into digital signals is called demodulation. These conversions are done because we connect to Internet using telephone line, which is not capable to transmit digital signals, but our computer produces digital signals. So to make signals suitable to transmit through phone line and to convert the analog signal received through phone line for computer we use MODEM