The Full-Form of MODDEM is Modulator Demodulator.

A modem or broadband modem is a hardware device that connects a computer or router to a broadband network. For example, a cable modem and DSL modem are two examples of these types of Modems.

A broadband modem is an external device that connects to your computers and other network devices using either a network cable or over a wireless connection.

Today, a “modem” is most often used to describe a broadband modem. However, it also describes what was initially considered a modem (described below) to connect to the Internet. To help prevent confusion, use the terms “broadband modem” and “dial-up modem.”

To help prevent confusion between a broadband modem, you can refer to this modem as a dial-up modem.