Modems are computer hardware typically used to transmit digital data over a phone line. The working of modems can be easily understood from this. Modems always work in pair. The sending modem converts computer’s digital information into specific frequencies compatible with the phone line, the process is called modulation. The receiving modem decodes the signal back into the digital information, the process is known as demodulation. In wireless modems, digital data is converted into radio signals and vice versa.
Origin Of Modems
The requirement of communication between distant computers led to the usage of phone line for data transmission. Since the phone lines were designed to carry analog information (voices) only and computers and its related network devices work in digital form, a interface was needed to bridge this gap, which could act as a converter between the two systems. The result came in the form of Modems
Initially modems were primarily used to communicate data between terminals and a host computer. Later their use was extended to communicate between end computers. It was around 1960 when modems came into existence. 1960s were the age of time-shared computers. A business would often buy computer time from a time-share facility and connect to it via a 300-bit-per-second (bps) modem. Now modems are used for different functions. Their applications include textual and voice mail systems, facsimiles, and they are integrated into cellular phones, pdas, and notebook computers enabling them to send data from anywhere. All these needs have increased the modem speed up to 28.8 kbps.
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