When the signal reaches the receiving computer it is converted back from analogue to digital form. A process called DEMODULATION. Modems are usually used to connect a computer to the Internet and to send and receive faxes via the computer. Modems constantly check whether the information was received properly or not. The information is broken down and sent in groups called PACKETS. Each packet is checked for errors and is re-sent if there is an error. Click on the link below to see how the modem works.