Modem

A modem is like a telephone for a computer to communicate with other computers over telephone lines. Broadly, a modem’s performance depends on the characteristics of the modem and those of the telephone line it is working with. The condition of telephone lines varies widely across the country. So how your modem works will depend to a large extent on the telephone line.

There’re several different types of noise that can happen either individually or in combination in a telephone line. Different modems react differently to these. And there’s no way you can identify which of these conditions affect your line. So nobody can correctly predict which modem will work the best on your line.
Test it on your phone line
There’s no other way out. You’ll have to convince your vendor to test the modem at your place, and to take it back if it does not work properly.

Internal or external?
If you’re buying a modem separately, go for an external fax-modem. External ones are easier to install. They cost Rs 2,000 upward. Buy the cheapest one that works okay with your line, giving you a steady high-speed connect for at least an hour.
If you get an internal modem card pre-installed when you buy a new PC, that’s okay, if it’s a 56 kbps fax-modem. An internal card does have one advantage: it reduces clutter. Again, it helps to check that it’s working okay on your line, else you may need to change it
Other modem features
True plug-and-play with USB
If you’re looking for swift installs and convenience, go for a USB modem. They cost about Rs 4,000.
The answering machine modem
If you’re looking for a modem that’s also a digital answering machine and a fax machine, go for a message modem. Message modems can store voice messages and faxes even while the PC is switched off. Once the computer is switched on, these messages are transferred to it and can then be heard or viewed. Some also let you retrieve the messages from a remote location—all you have to do is call up your message modem.