Modems

Modems are used for “dialup” communications; in other words, they dial up a network connection when needed, and when the transmission is completed, the connection is disabled. They work with ordinary telephone lines. When you want to send data across telephone lines, the modem takes the information from digital format and converts it (or modulates it) into an analog signal. The receiving modem converts the analog signal back into digital form (or demodulates it) to be read by your computer. This modulating and demodulating gives the modem its name.

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