Running Microsoft Windows 2000 Professional

To use Phone Dialer to place a call over ordinary telephone lines, you must have a modem installed in your computer. Unless you're using a voice modem, you must also have a telephone connected to the modem.

To communicate using a network connection (including an Internet connection), you'll need a sound card, speakers, and a microphone. You'll also need a camera if you want others to see you.

You can participate in a videoconference without a camera; you can see others, but they can't see you. Similarly, you can participate if you don't have a microphone. You can see and hear others, but you can't be heard—and what fun is that?

And the people receiving your calls? To receive calls on their computer, your recipients also need to have an Internet telephony program, and the program must be running when you call. They can use Phone Dialer, Microsoft NetMeeting, or a third-party telephony program.

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