CYBER NOTES by Dave Benore August, 2004

A Primer about Computer Hardware—or What Is It and What Does It Do?

What does a computer need? It needs a “brain”, a memory, some “training”, and one or more ways to communicate with people.

The brain is the central processing unit, called the CPU for short. It is technically a microprocessor because it is very small (micro) and it processes instructions (processor). It’s also called “The Chip”. For PCs the current CPU is the Pentium IV microprocessor, made by Intel. Apple’s Mac computer uses a Motorola chip but I don’t know the current name for it. (PCs you may know are the design started by IBM. IBM called them “personal computers” (PC).

The memory comes in two flavors; one that works very fast but only while the computer is running, called the RAM (random access memory); and one that works while the computer is on or off, called the “hard disk” (because it is hard, as compared to “soft” which some discs are--the floppy disks.

Training is accomplished by giving the computer “instructions”, called “programs”. Programs tell the computer what to do, like potty training your child! (Actually, that’s a pretty good analogy.) Computers, without programs, are totally stupid paperweights!

Communications are handled by a variety of ways. You talk to your computer by using a keyboard, a mouse, a floppy disk drive, a CD or DVD disk drive, a scanner, or by simply yelling your head off. (It doesn’t listen very well though!)

Your computer talks to you by using a monitor (looks like a small TV set), by printing on paper, by generating sound through speakers, or occasionally by doing absolutely nothing except glaring at you. (This is called “locking up”. Something has gone wrong with the programming and the computer doesn’t know what to do, so it does nothing. The usual cure is to turn it off and start over. I wonder if that would work with children?)

Where is all of the physical stuff like the CPU, the hard disk drive, and the memory? They are either mounted on the “motherboard” or are plugged into it. (I wonder why they call it the motherboard. Are the ladies getting another bum rap somehow?) The motherboard (a printed circuit board) and “her” stuff are mounted inside the metal case we call the computer.

The training instructions and information are loaded (copied) onto the hard disk either by using the keyboard, floppy disks, or CD/DVD disks. When the computer runs a program it normally copies its instructions and related data from the hard disk into the RAM. The CPU gets the instructions and data from RAM, processes them, and sends the output (answers) back to RAM. Because of the programs’ instructions, the answers are usually displayed on the monitor. The answers can be printed on paper for a record, and/or, if you are smarter than the computer, you have them copied back to the hard disk. Otherwise, when you turn off the computer, all would be lost because RAM goes blank when the power turns off! Unless told to do so by you, the computer will not save the answers. I told you the computer could be stupid, didn’t I?

Seriously, no one can hurt the hardware by punching the wrong keys. You can goof up the software sometimes, but that is relatively easy to fix. So don’t be afraid of your computer. It is a lot dumber than you may feel you are! You will get smarter about your computer as you use it. Your computer will never get smarter than you! It never gets smarter than the day it was made. In fact, every time you turn it on (boot it up), it retrains itself from scratch! A computer is nothing more than a fantastically fast and flexible programmable calculator—but what a job it can do for you! Happy computing!!