MODULE R2 - THE COMPUTER
Components of a
System Unit - Body of the computer containing the
electronic parts that operate the computer, the connections to the other components, and
the disk drives.
CPU - The central processing unit is the brain of the computer.
It performs the analytical, computational, and logical functions that occur inside the
Memory - Stores information that will be processed by the CPU
and is measured in terms of bytes. Each character of information is stored in memory as
1 byte = 1 character = 8 bits
1 bit = 1 or 0
Kilobyte - approximately 1000 bytes.
Megabyte - approximately 1 million bytes.
RAM - Random Access Memory is the systems workspace. RAM
is used to store and retrieve information while you work on the computer. RAM is the
computers short-term (temporary) memory, so data in RAM is lost when the computer is
ROM - Read Only Memory is the memory in the computer where the
contents remain permanently. For the most part, ROM contains programs that the computer
needs when it is first turned on.
Disk Drives - Disk drives are devices inside the system unit
that read and write information to or from a disk. Data stored on a disk is not lost when
the computer is turned off.
Floppy Disk - 5 1/4", 3 1/2", or 2 1/2" in size
and are a removable storage media where data is kept. Most floppy disks hold from 360
kilobytes to 1.44 megabytes of information.
Fixed Disk - Known as hard disks. These disks are contained
within a high-speed, large capacity disk drive inside the system unit. Fixed (hard) disks
cannot be removed from the computer. They range in capacity from 20 megabytes and larger.
Monitor - Displays information typed at the keyboard or contained
in a program.
Monochrome - displays one color (amber, green)
Color - displays many colors.
Keyboard - Allows communication with the computer. Keyboards come
with different set-ups. The most typical are the XT style and the AT style.
Printer - Creates permanent output from the computer (hard copy).
Dot Matrix - Produces less than letter-quality print at low
Ink Jet - Produces letter-quality print at moderate cost.
Laser - Produces excellent quality output and is most expensive.
Almost any kind of application software needed is already available,
called Packaged Application Software. Programs are already written and tested and may be
purchased off the shelf in retail computer stores or through mail-order outlets. This
packaged software falls into two categories, special purpose and general purpose.
Special Purpose Software
Dedicated to performing tasks such as payroll, accounting, bookkeeping,
education, entertainment, or statistical analysis, the programs contain built-in problem
solving features specially designed for those particular tasks.
For research purposes, the special purpose software that will probably
be of most benefit to you is the statistical analysis software. Some of the most used
statistical packages include SYSTAT, SAS (Statistical , and SPSS (Statistical Package for
These programs allow the researcher to input the data gathered and
analyze it using a wide range of statistical tools. They make the task of statistical
analysis much more manageable and much less menacing.
Although programs such as these make statistical tools easier to apply,
they are not a substitute for a thorough background knowledge of statistics. An
understanding of statistical terminology and application is a must when working with one
of these programs. The many statistical software packages available, when combined with a
good understanding of statistical principles, can help make the research project much
simpler and more enjoyable.
General Purpose Software
Adaptable to a wide variety of tasks, such as word processing,
spreadsheet calculating, record keeping, graphics, or communications, the user defines the
problem and the procedure and uses the software to assist in preparing a solution.
In conducting research, the most widely used general purpose programs
are word processors, spreadsheets, databases, and graphics. These programs can be very
helpful in recording, sorting, revising, and storing the information needed for the
The most widely used microcomputer software is word processing
software. This software lets you create, edit, format, store, and print text. The one
thing that makes a word processor different from a typewriter is the ability to store
information. Since the document can be stored, it can be retrieved at another time,
changed, or reprinted. The timesaving factor is that the unchanged parts of the saved
document do not need to be retyped and the whole thing can be reprinted as new.
Some of the most widely used word processing programs are WordPerfect,
Microsoft Word, and Ami-Pro. In writing a thesis or dissertation, you will find these, or
any other word processor, to be very valuable and helpful tools.
Used to organize numerical data, a spreadsheet is a worksheet divided
into columns and rows. Manual spreadsheets have been used for centuries, but these are
very tedious to prepare and when there are changes to be made a considerable amount of
work may need to be redone. An electronic spreadsheet is the same as a manual spreadsheet
except that the computer does all the work. In particular, spreadsheet software
automatically recalculates the results when a number is changed. If calculations are
called for as a part of a research project, a spreadsheet is a way to make the task of
figuring these much simpler and more manageable.
Some of the most common spreadsheet programs on the market are Lotus
1-2-3 and Microsoft Excel. These and other programs like them will make handling numbers
and calculations much less tedious.
Software used for database management, the management of a collection
of interrelated files, handles data in several ways. The software can store data, update
it, manipulate it, and report it in a variety of forms. Database software is very helpful
for storing research data that will be updated and manipulated as the research project
Some of the most widely used database software include Microsoft Access
and Borland Paradox. These and other database programs are very useful to the researcher
who must keep track of a large quantity of data.
At some point you may wish to present your research project to a group
of people. It is important that your presentation be easily understood and interesting.
Graphics programs can help make dry, boring text more understandable and memorable. Most
graphics software allows the user to enter raw data and can transform this data into a
graphic representation such as a bar graph, pie chart, histogram, or map. These graphics
are valuable for building charts that can be integrated into the finished product of your
Many word processors, spreadsheets, and databases have graphics
capabilities that may be helpful in presenting research material. Some of the programs
designed specifically for graphics are Harvard Graphics, Lotus Freelance, and Microsoft
PowerPoint. These and many other programs can help make your final report more interesting
The microcomputer is a very valuable tool for the researcher and can
make the task of gathering, manipulating, storing, and reporting information much simpler
and more enjoyable. The researcher should look for the particular software that can help
make his or her job more rewarding. An initial investment of time or money in computer
knowledge and software will pay huge dividends to the researcher that can make the best
use what the microcomputer has to offer.
1. Name the two types of memory units.