What is Modem in Computer


Modem is a short form of “Modulator-Demodulator.” It is a computer hardware device. A modem transmits data by modulating one or more carrier wave signals to encode digital information, while the receiver demodulates the signal to recreate the original digital information. A modem is a small box that connects your devices to the Internet using cables. The goal is to produce an electrical signal that can be transmitted easily and decoded reliably. Modems can be used with almost any means of transmitting analog signals, from light-emitting diodes to radio. A modem acts as a digital translator, taking an information signal from your cable, fiber or phone lines and making it accessible to your computer.

Features of Modem

There are some important features of Modem :

  1. Auto-answer – A modem’s ability to automatically answer the phone after the phone rings a set amount of time.
  2. Data/Voice – Modems with voice capability that switch between a voice and data communication.
  3. Fax – Fax modems can send and receive a fax with the proper software.
  4. V.90 – The standard that the modem uses also allows it to communicate at an optimal speed. When first introduced, there were multiple standards, but nearly all 56 K modems use the V.90 standard.

Types of Modem

There are different types of Modem :

1. Dial-up Modems

Dial-up Modems is a type of modem that is uses to make connection with ISP using of analog signals. It transmits analog signal via telephone lines. There are two types of Dial-up Modems :

  • External Modem – An external modem is a standalone modem that does not contain a router. It directly attached to a computer via USB, Ethernet or sometimes wifi.
  • Internal modem – An internal modem is a type of modem which is attached to the motherboard.

2. Router/Modem Combo

A router/modem combo is a type of modem that is contained within a router, which allows multiple computers/devices to connect within one network. It means networks don’t need a separate modem and router.

3. Digital Modem

A Digital Modem is also known as a broadband modem. There are four types of Digital Modems

  • DSL Modem – DSL stands for “Digital Subscriber Line”, and it is also known as “Broadband Modem”. It offer broadband services for using of several types of internet connections. DSL modems are comfortable for higher internet speed.
  • Cable Modem – In the Cable Modem uses coaxial cables, which are attached to the back edge of the modem.
  • ISDN Modem – ISDN modem is an external device. It is used to make calls and connect to the internet.
  • ADSL Modem – ADSL stands for “Asymmetric Digital Subscriber Line”, and it is also known as “Broadband Modem”. It transmits digital data at a high bandwidth over existing phone lines to homes and businesses. In order to access ADSL, a Digital Subscriber Line modem (DSL modem) is installed at the client side.

4. Fiber Modems

A Fiber modem is a type of modem which acts as a connecting interface between an electronic device and an internet network. It uses a fiber optic cable network to transmit signals. It transforms electronic communication signals via a fiber-optic network.

5. Integrated Modem

An integrated modem is a type of modem which is contained within a computer in the form of USB or as a PCI card. It only allows the one computer to connect to the internet.

6. Wireless Modem

A wireless modem is a type of modem. It is also known as a radiofrequency modem. These modems make a wireless connection from your device to the ISP provider. It can be used on smartphone, laptop and desktop computers.

7. Telephone Modem

In a telephone modem, a computer is connected to a network of other computers via telephone lines. This is a low cost modem.

8. Satellite Modem

Satellite Modem is a device that provides internet connection through satellite dishes. It transfers the input bits to output radio signals and then executes vice versa. It is costly as compared to all other modems.

9. Fax Modem

A fax modem is a data modem that enables a computer to transmit and receive documents as faxes on a telephone line.

10. Intelligent Modem

Intelligent Modem is a type of modem that responds to commands and can accept new instructions during online transmission.

How does a Modem Work?

A modem has two plugs, one plug connects to the telephone line and the other connecting to your computer or a WiFi router.


The modem takes the digital signal from the computer and combines it on top of an analog telephone signal so that it can be transferred through the telephone line. Since your modem sends information through a telephone line by modulating digital signals, it also needs to have another kind of translator that helps it demodulate the analog signals it receives via the telephone line.
That’s why a modem is named as such, because it both modulates and demodulates signals.

In this article, we described What is Modem in Computer. Hope you have got your problem’s solution! Thanks for reading this. If you want to know more details about How to Connect Modem to Computer for Internet. Click Here