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Christian InTech Articles - Computers
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Computer Motherboard Guide
The heart of any computer is the motherboard. It is that big
board inside the computer that everything is connected to. It
performs the role of traffic lights and policemen, directing
flows of information to where they are needed, when they...
Having A User Friendly Website
Let's look at what your user wants to see at your website.
1. No Flash
For many who visit your website time is money for you and for them. The last thing people need to see is a slow loading flash front page. Unless your flash page is very...
Know linux
Linux Linux essentials: •It's free for download but you have to pay a tiny bit to mail order it or buy it from a company. If you're getting Linux for more than 2-3 PCs, you can also get training and support at a small free, if you choose to...
PRINTING YOUR WAY TO A GREEN EARTH
When we say new technology the first word that pops in our minds is computer. Computer dominates our planet. The next word to associate computer is printer. In almost all industries, a computer without printer is useless because printer does the...
Recover Deleted Data Easily
With such a multitude of disk recovery software available, both in computer stores and on the internet for downloading, there is a good chance that you can recover deleted data. If you've accidentally erased files that you need for whatever reason,...
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It's A Binary World - How Computers Count.
Many have cursed their computer for taking things too literally!
It's easy to blame the computer when something goes wrong.
You get to the checkout at the market, and the item you bought
'on special' comes up at the full price. The manager has to be
called to fix it up, and what does he say? "We've been having
problems with the computer, it gets the wrong price on some
things."
You put in a list of addressess to your Word processor, and
print off party invitations for next week. Then you find that
today's date has been inserted in the signature block - by the
computer!
Maybe you have heard the expression 'Garbage in Garbage out"?
Someone, at some point instructed the computer to do what it
did, It didn't decide to screw you up deliberately. Computers
can only do what they are told, they are more logical than Spock
and they take everything literally.
We are going to look at why they are so pedantic!
The world around us has many aspects which work in the same way
as a computer. There are many examples of opposites, for
instance Up and Down, Left and Right, Forwards and Backwards. A
light may be On or Off, maybe it's Night or Day. Yes or No? You
can think of many others. This system of two possible states is
called a Binary System, if it's not one, it must be the other.
A computer uses the Binary System to perform all its functions,
the basic unit, originally a vacuum tube, then a transistor,
then a chip, is used thousands of times over to make the total
unit. The light being On or Off which we mentioned above is
controlled by a switch. In the computer this switch is a
transistor, which is either On or Off.
Now we get to the Math! Don't worry, it's very simple Math! In
fact it's so simple we only count up to 1. That's right, we can
only have two states so we count from 0 to 1. (That's another
thing computers are pedantic about, they insist on starting at
zero).
The Binary system is a Number System. You are familiar with the
Decimal system which has 10 numerals 0 to 9 (think like a
computer 0 comes first). You can make up all sorts of number
systems for whatever purpose you want. You probably know about a
dozen (12) and have also heard of a half dozen. If you've used
your computer much you may have come across the Hexadecimal
system.
This one has 16 'numerals' 0-9and A-F. Another number
system used by computer people is the Octal system which has 8
numerals, 0-7.
Ok so how do we count with only 0 and 1. Simple, in exactly the
same way you count in decimal. The first ten numbers are OK,
0-9, but what next? We start again but add in a 1 making 10 or
"one, zero". This gets us to "one, nine" and we go to "two,
zero", and so on up to "nine, nine" then we again add a 1 to
make 100 - "one, zero, zero."
If you've followed me so far you are ready for the Binary
sequence, it's much simpler. Starting off at zero we have 0,1 -
and that's it. We follow the same rule and add in a 1, making
"one,zero". Next come "one, one"; then "one, zero, zero"; -"one,
zero, one"; etc. These are equivalent to Decimal 0,1,2,3,4,5.
How does this relate to computers? That's next.
In our computer we have transistor switches, as described above.
For the math example we just looked at, we need 3 switches.
These each represent a Binary Digit, or Bit. To represent a
Decimal 1, these switches would be OFF,OFF,ON or 001. For a
Decimal 5 we would have ON,OFF,ON, or 101. By extension you can
see that with 4 switches we could go to 1111 or 15 Decimal.
Another point to note is that each binary digit, or bit, has a
value. Just as in Decimal we have units, tens, hundreds, etc. in
Binary the values are 1,2,4,8,16,32,64,128 etc. etc. The binary
code 1111 mentioned above is thus 1+2+4+8=15. If you wanted to
work out what binary 100101100 was in decimal, you could add up
the individual values. In fact people who work on the basic
machines need to know "machine code"! To them 1111 would be F in
Hexadecimal or 17 in octal.
This probably seems a very long-winded way to work out numbers,
until you remember that these 'switches' can operate at
nanosecond speed or 1,000,000,000 times per second, large
calculations become possible.
Thats probably enough to digest in one go. Next time we will
look at how a computer adds and multiplies.
About the author:
Tony is a qualified and experienced tech support engineer on
computers fom laptops to mainframes. He is Webmaster of and
contributor to http://www.what-why-wisdom.com/ which looks at
everything you can do at home now that a computer is part of the
everyday lifestyle.
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