CertiGuide to A+ (Core Hardware)  9  Chapter 0000:  The Start of the PC       9  IV  PC Technology Evolution

2002 and Beyond 1 V  Electricity

In many ways, a computer system is like an airplane. They are both a collection of spare parts flying in close formation.

In each case, they are a system that depends on the close timing and performance of a number of subsystems. In the computer case, there are three major subsystems. They are the CPU, RAM, and storage.

The first subsystem is the Central Processing Unit (CPU).

This is the brain that would be considered central command. In a desktop metaphor, the CPU is you sitting behind the desk, deciding what to do next and controlling the flow of action.

The second subsystem is the Random Access Memory (RAM). The computer functions much like your desktop where you spread your work out.

How much RAM you need, depends on how much work must be spread out. The more projects you have going at the same time, the more desktop you need. The same could be said of RAM. A large program or even a series of small programs all consume this resource.

The third subsystem is storage, such as a hard drive. Using the desktop analogy, the hard drive or CD acts as a filing cabinet for your projects. Just as in the physical office, the more projects you need to store, the more storage space you need.

Further, the more drawers you have to stuff things in, the better the chances are for a particular file to be lost in the clutter. 'Spring cleaning' a large hard drive can be just as joyous as cleaning an attic with 30 years of collectibles.

A common denominator among all these components is the fact that they need energy to make them work. In the next section we will dig deeper into that energy source.

2002 and Beyond 1 V  Electricity