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		A modem, short for modulator/demodulator, is a device that converts (modulates) computer signals into tones that can be sent over phone lines. (See Figure 6-5.) A modem on the receiving end converts (demodulates) the signals to their original computer readable form. There are two kinds of modems: acoustic-coupler and direct-connect. With an acoustic-coupler modem, you put the telephone handset into a pair of rubber cups. With a direct-connect modem, you plug the modem directly into the phone jack. The advantage of an acoustic-coupler modem is that you can use it from a phone that doesn't have a removable phone cord. The advantage of a direct-connect modem is that the phone signals don't have to travel through the handset, so there's less distortion. Different modems send and receive information at different speeds, measured in bits per second (bps), often referred to as the baud. The most common baud for modems is 1200. You can also get modems that send and receive data at 300 baud, 2400 baud, or at your choice of speeds. Modems that operate at 1200 baud cost more than 300-baud modems, but they're much faster. Because you may be paying long distance phone rates while your modem is sending and receiving information, the time you save with a faster modem usually justifies the higher initial cost.


Figure 6-5 What the modem does


		There are two types of monitors: monochrome and color. Monochrome monitors come in three varieties: white, green, or amber on black. Some studies indicate that an amber display is easier on the eyes; others, that a green display is easier to read. Some people prefer black and white because it more closely resembles a typewritten page. The best choice is the one that looks best to you.

Figure 6-6 Monitor