A basic knowledge of how the computer works can help you understand what is happening, to know when you are having a problem, and to describe the symptoms.
In order to understand how a computer works, we must deal with two concepts: hardware and software. Hardware is the name for the mechanical and electronic components of a computer. Software is sets of instructions that tell the hardware what to do.
The PC (personal computer) is basically a desktop computer. At first glance, you can see that it consists of three visible parts:
The Computer (System Unit)
The Monitor
The Keyboard
It consists of:
- Mother Board that holds all the circuitry power supply which is a transformer which takes the 11V at the wall down to 6V and has a fan to cool the computer
- The Microprocessor (386, 486, Pentium, Pentium II) that determines the speed data is manipulated and stored in memory
- The Interface Cards that plug into the expansion slots on the motherboard, like video cards for the monitor, sound cards, modem cards, and network interface cards
- Some printers and mice plug into cards if not already built into the motherboard
One decision to make is how much power the Mother Board needs – as in processor speed. You hear terms like 386, 486, Pentium, Pentium II to denote the processors used to run the system. Even within these names for the system, you have to deal with processor speeds, like 25 megahertz for a 386 computer, up to and beyond 233 megahertz for a Pentium II processor.
As with most things in life, it comes down to what are you going to use the computer for, and how much are you willing to pay to get the fastest machine for the job.
High density monitors have a pixel mix of 1280 x 1024 pixels. If the goal is to do a lot of graphics where edges need to be smooth, the more pixels per inch, the better. Normal word processing and spreadsheet processing get along just fine with 640 x 480 pixels per inch.
Specialized keyboards also are available for the "Natural" feel for the wrists by splitting the keyboard in the middle so the wrists can rest naturally instead of straight ahead.
Since more and more people have carpal tunnel syndrome and keeping the wrists rigid while typing is painful, some people are opting for the alternative keyboards, as well as keyboard drawers so that the keyboard isn't too high on the desk plus wrist pads to relieve tension better.
There are many types of mouse devices to choose from, such as Two button, Three button, Trackball, Touch pad, and Joy stick. The most common mouse is a two button type. The button your index finger rests on is the normal click side and the other side is used infrequently for alternate menu selections. You can set up your operating system to recognize the mouse being used by a left-handed person or right-handed person – translation: the activate button is switched.
Hard Drives are usually designated as Drive C (or D or E, if multiple drives are used).
High Density 3 ½" Disks hold 1.4MB
Low Density 3 ½" Disks (not usually available)
High Density 5 ¼" Disks (usually found on older machines)
Low Density 5 ¼" Disks (usually found on older machines)
Floppy Drives are usually designated as Drive A or Drive B if more than one floppy drive.
Typical Zip Drives will hold 100MB of information and can be used to back up critical files, or keep confidential information on a separate disk.
If the proper sound cards are on the machine, the CDROM can also be used to play audio CDs.
The most popular printer for the office has been the HP Laserjet. This is great for black and white print, but to add color, the HP DeskJet printers can also provide this feature.
Most printers require a parallel port on the PC (usually standard with all system units) and a cable connecting the two together (the printer and the PC).
Other than that, all you have to worry about is keeping it full of paper and ink.