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					                      The Real Beginner’s
               Introduction to Computers
       Fifty years ago there were only two computers in the world and IBM was
predicting that only four would ever be needed. But soon, IBM was forced to change
its mind because technology advanced at a much faster pace than anyone could ever
have predicted. Today there are millions of computers and millions more will be
build in the next few years.

1. A Short History
       In the 1950s large computers called mainframes were affordable only by
governments, universities or corporations. But by the 1960s – with the introduction
of the transistor – computers shrunk to the size of cabinets while dramatically
increasing their power. These computers were called mini computers because they
were much smaller than the large mainframes, but still further decreases in size and
increases in computer power were to come. About 1970 the microprocessor, which
put the calculating capability of a computer on a piece of (silicon) material the size of
your fingernail, was introduced. Silicon was produced from sand which was readily
available and therefore relatively inexpensive. Within ten years (by 1980)
microprocessors were being built into smaller computers which were called
microcomputers. The first microcomputer designed for the mass market was called
the Apple II. (There never was an APPLE I). The computer which provoked
enormous changes in office work and communications was the 1981 IBM-PC. It
sparked a massive purchasing of microcomputers which is still going strong. Today,
tiny computers are being installed into all kinds of products: cars, refrigerators,
telephones, houses and many other things. The computer will alter how we think
about work, communication, leisure and family-life, no matter where we live. In the
advanced electronic world (what used to be called the “industrialized” world) the
computer will promote movement towards more knowledge-based work. For the
developing world it may mean new ways of catching up to the economically richer
countries or, sadly, increased income and knowledge gaps between the economically
rich and poor nations. It will definitely increase the trend to greater globalization. We
need to pay attention to how the computer works, and how it effects our societies and

2. What is a computer?
          A computer is an electrical appliance which allows people to store
information, manipulate it, and print it out. This information could be union dues,
address lists, letters and much more.
          The computer manipulates data in the form of 1s and 0s. The data is held on
chips or in the memory of the computer in the form of electrical impulses: if there is a
little electrical charge in a certain area of the chip then the computer considers that a
ONE. If there is no charge the computer interprets that as a ZERO. A collection of 1s
and 0s makes up a number, or a letter. For example, 01001110 could stand for the
letter A.
          You don’t have to know how a computer works in order to use it, but you do
have to know a little about its various parts (called the “hardware”) and its
instructions for manipulating the information (the “software”). Fortunately this is
much easier than fifty years ago!

3. Computer Hardware
          Computer hardware is computer equipment – stuff you can touch. Physically,
the computer consists of: the system unit (the box which holds the microprocessor,
memory chips and other things), a monitor and a keyboard. It may also be connected
to peripherals such as a printer. Or it may be tied to other microcomputers (via a
Local Area Network). Here’s what all that means:
          The system unit is the main part of the computer. It is what does all the work:
it takes commands from the keyboard, collects information from the hard disk or
floppy diskette, manipulates it, and then displays it on the monitor screen or prints it
out on paper. The hard disk (which looks like a filled-in steel doughnut) is a piece of
equipment inside the system unit which holds lots and lots of information. The
floppy diskette (which isn’t really floppy anymore) is the square piece of plastic
containing recording tape which can hold your documents or other information.

        The system unit has a microprocessor - the thing which co-ordinates the
information-handling activity. Microprocessors used to be named with numbers such
as 386 and 486, but today it has names such as Pentium II and III. The faster the
microprocessor, the faster the information is manipulated.
        The system unit also includes many memory chips. These are pieces of silicon
which contain spaces to enter the 0s and 1s which the computer works with. Some
memory chips are called ROM (READ ONLY MEMORY) because the information
on them can only be read, not changed. Other memory chips produce RAM
(RANDOM ACCESS MEMORY) which is available only when the computer is
turned on. The computer puts data into the RAM memory in order to work with it. If
the information in the RAM is not saved by putting it on the hard disk or diskette it is
lost when the computer is turned off. This is why people are told to periodically save
their information (which means moving it from the RAM memory to the hard disk or
a diskette).
        The monitor is a television-like thing which displays the information, such as
text and pictures. And just like a television, it can come in different sizes and
resolutions. Resolution refers to the number of tiny little pixels it takes to produce
characters or pictures on the screen. A monitor with more pixels will be clearer and
easier to see than one with less pixels.
        The printer, of course, is the thing which prints out the information
manipulated by the microprocessor. Today printers come in basically two formats:
laserjet and inkjet. A laserjet printer works almost like a little photocopier. An inkjet
printer squirts ink on to the paper in the shape of letters or pictures.
        Microcomputers can be either standalone (which means they are not connected
to any other computer) or part of a Local Area Network (a LAN.) Microcomputers
tied together in a LAN can pass information amongst themselves (such as word
processing files) or share equipment (such as a printer or a connection to the Internet).

4. Computer Software
       Computer software is the name for the programs which provide the
instructions which tell the computer what to do. For example, a computer program
called a word processor will tell the computer how to manipulate text so people can
type characters, change the characters, save them on the hard disk or a diskette, and
print them out. It could be used to produce letters, manuscripts and other text-based
       A spreadsheet is a program which does the same thing as a word processor,
except with numbers. It allows people to type numbers on the screen and then work
on the numbers with arithmetical operations such as addition or multiplication.
Union dues, for example, could be calculated using a spreadsheet.
       Other computer programs include: desktop publishing (which can manipulate
text and graphics to produce leaflets) databases (which store information such as
address lists to produce mailing labels) and communication programs (which allow
computers to communicate to other computers).
       An operating system is the basic program which tells the computer how to
work with other equipment (such as printers), manipulate files and work with
programs. The most popular operating system is called Microsoft Windows.

5. The Computer Measuring System
       The ZEROs and ONEs produced and manipulated by computers are measured
with a metric system. This system is used to measure the amount of information held
by the computer, the size of the hard disk or diskette, the amount of RAM that is
available and the size of programs.
       It all starts with a BIT: which is a ONE or a ZERO. If you put eight bits
together you have a BYTE – which is the amount of bits you need for a text
       1 BIT              = eight BYTES =                     - ONE character
       A KILOBYTE         = (about) 1,000 bytes =             - one double spaced page
       A MEGABYTE = (about )1,000,000 bytes =                 - one diskette
       A GIGABYTE         = (about) one thousand million. = – lots and lots!
        Programs can take up megabytes of storage space on a hard disk. As well,
the parts of the program you work with can take up space in the RAM memory. That

is why sometimes a computer message will tell you “Not enough memory”. It means
that there is not enough RAM for the program to operate because: 1) not enough
RAM chips have been installed or 2) other programs are using the computer’s RAM.


       In the end though, it doesn’t matter if you know all this stuff about computers.
The important part is that you try to understand how they can help you in your work
and the possible effects they will have. To learn how to use a computer, do what the
experts do: practice little things and learn while you go.


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