A modem is what connects your computer to the Internet. With the rising popularity of the Internet, a modem has become as important as the mouse as a standard home PC accessory.
Modems come in various shapes and sizes.
The widely used ones are those that use ordinary phone lines and others that use cable TV networks for connection. The basic factor that determines a modem s performance is the maximum speed at which it is capable of sending and receiving data. All modems available today are capable of speeds up to 56 kbps. External modems are housed in a box that sits on top of your PC and connects to it via a Serial Port. Internal modems, on the other hand, are housed inside the computer s cabinet itself as a card that plugs into an empty expansion slot on the motherboard.