Understanding Hardware Types

Before you can make an informed decision about adding a new piece of hardware to your computer or network, you have to understand how hardware connects to your PC and what you need to make that sparkly new toy work.

Juggling internal and external devices

An internal device is one that goes inside your computer's case. An external device has its own case and is connected to your computer by a cable.

An internal device is more convenient to use. If you have to move your computer, the internal device goes right with it. There's no cable or separate power cord to get tangled and catch dust. But you have a physical limit on the number of internal devices you can cram into a box.

On the other hand, an external device is often more flexible - and it's almost always more expensive. If you have more than one computer, you can move an external device from one to another as the need arises.

An internal device may be an adapter card that plugs into one of the slots on your computer's motherboard, or it may be connected to a controller by an internal cable. All external devices are connected to a controller.

The type of interface that a device has determines the type of controller it needs. (The next section explains interfaces.) A single controller can operate several devices with the same type of interface. Some types of controllers are built into the motherboard; others must be added as adapter cards.