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Modems are hardware devices commonly used to connect different computers across the globe, exchanging, retrieving and posting data in a couple of seconds which traditionally would have been almost impossible to achieve. And it does so by converting digital information stored in the computer into analogue signals, transmitting them via telephone lines and back into digital packets by the receiving modem. Modems transmit data or information and change or modulate the format depending upon whether they are talking to the computer or are in the process of using a phone line to transmit data to another modem. Modems are used to connect to the Internet also. It is not common to be subjected to faulty transmissions while downloading files from a remote computer or in the initial stage, struggle to establish a connection in the first place. If the speaker of the modem is activated, the standard beeps or rotary pulses can be heard when the number is dialled either manually entered or picked up from a software address book. When aroused by the call, the modem on the receiving end interrogates user modem and settles on a common interface or connection rate as long as the connection or session lasts. The receiving modem then talks to the computer it is connected to and receives information about the connection rate at which connection is established between a computer and the modem connected to it, which can be less or more than the one established with user modem connected rate at which connection is established between a connecting and the remote modem. If the destination computer transmits data to its connected modem faster than what user modem can handle, the data is compressed by the modem on the fly so that user modem can receive data without waiting. This compressed data is then decompressed by user modem and served to user processor. After such a standard pattern is established and as long as the phone line is engaged, a channel or pathway is created between both the computers, no matter how geographically distant it might be. If the connection drops for some reason, the entire process of initiation and protocol establishing has to start all over again. Unlike connecting via network interface cards and physical cables, connection to a network of computers like the internet via a phone line or dial-up adapter, is never permanent, and lasts only as long as the call status is active and is restricted to a maximum bandwidth as accommodated by user modem. A standard modem has a power outlets, two phones cable jacks and a serial connector for connecting to the ‘Serial’ (COM) port on the back of a computer. When the modem is turned on, a set of lights on the front panel light up and indicate the initialisation and status of the modem, both when idle and when sending and receiving data if it's an external modem. The instructions that tell the modem how to transfer data are stored in the modem's ‘Read Only Memory’ (ROM), embedded circuitry and chipset. If the modem has flash ROM, user can add newer features or update into the latest technology by running a small software program or utility if the modem can be upgraded via software. Modems, both of external and internal type, have their advantages and disadvantage. External modems are the easiest to install and offer some features that internal modems don’t. The external lights on a modem give a realistic indication of whether data is being transmitted and how consistently. But since an external modems is connected to a COM port, it's performance is dependent on the kind of UART chip the COM port uses. An UART chip other than 16550, which has 56 KBPS or 115 KBPS data transfer rate, will considerably decrease throughput of the communication port. Internal modem comes with the UART chip inside the PCMCIA card itself, which are 16550. But it can be quite time consuming and frustrating to install a non-‘Plug and Play’ (PnP) internal modem, which needs to be assigned a proper non-conflicting IRQ address. Relatively expensive, external modems come with a separate cable that connects to the COM port behind a computer, and so can easily be detached for troubleshooting purposes without having to open up the cabinet. On the other hand, internal modems are cheaper, cumbersome to replace and instead of a cable, occupy an ISA slot on the motherboard. Whatever type, make or model, the modem should support at least the 28.8 KBPS ‘V.34’ or 33.6 KBPS ‘V.42’ speed standard or ‘MNP1-5’ data compression standard. ‘Windows’ detects most PnP modems without difficulty by installing the appropriate ‘Device Driver’ (INF) files. But for the recently purchased modem, it is better to install the driver files from the installation floppy disk provided. The INF file interrogates the modem and detects its built-in features and displays it through settings in the control panel. Most modems will function by default, but some might require initialisation strings for the modem to dial out and establish connection to remote computers. It is advisable not to connect to the Internet when there is lightning in the sky. The charge from a lightning bolt can travel up the phone line and wreck sensitive electrical parts inside the modem and also inside the computer.