Meaning – The term modem, refers to a functional unit that modulates and demodulates signals. One of the functions of a modem is to enabledigitaldata to be transmitted over analog transmission facilities.
It also refers to a device that converts digital data from a computer to an analog signal that can be transmitted on a telecommunication line and converts the analog signal received to data for the computer.
The first modems were “dial-up,” meaning they had to dial a phone number to connect to an ISP. These modems operated over standard analog phone lines and used the same frequencies as telephone calls, which limited their maximum data transfer rate to 56 Kbps.