External computer devices

A computer will be useless if it was not possible to enter data to it, or to retrieve data from it.

Typical computer devices include the following: keyboard, mouse, monitor, printer, speakers, webcam, scanner a microphone. These are external devices.

There are also internal computer devices that extend its functionality.

These include the following items: sound card, optical drive a video card.

A computer will work without sound card or an optical drive. If motherboard has a graphical chip in it, then a computer will even work without an external video card.

I am describing a personal computer here and not a server.

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