=Hardware Internet=

As multimedia audio and video clips flood the Internet, people are upgrading their computers with modems that are capable of faster access and download times. A modem is the piece of hardware that lets your computer transmit data to and receive data from your ISP (Internet service provider). In turn, the ISP provides access to the thousands of servers that compose the Internet. There are a number of options for making this connection, but the deciding factor when selecting a modem is usually the speed at which it transmits and receives data.

The most common conduit for modem communication is the standard telephone line. This type of connection is used for internal, external, and standard PC Card modems. Other modem technologies include cable modems, which communicate with an ISP using coaxial television cable, and cellular modems, which use PC Card technology but also feature extra ports for connecting a cellular telephone to the PC Card or include built-in cellular capabilities. Another type of modem communication takes place using ADSL (Asymmetric Digital Subscriber Line) connections that use analog phone lines to transmit digital data. We'll explore each of these modem types and discuss the various computing environments in which you'll find them.

Internal & External Modems

Internal and external modems convert the PC's digital data signals into analog waves that are sent to the ISP over standard telephone lines. Similarly, when the modem receives analog signals from the ISP, it converts them into digital signals the PC can understand. This process is known as modulation/demodulation and is the origin of the word "modem."

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