From counting to computer by Catsbeauty

VIEWS: 7 PAGES: 2

									   From counting to computer

*Why is the decimal system so widely used ?
 As traders , the Babylonians needed a quick and easy
way of working with high numbers , and s they developed
a decimal system of writing numerals. They were also the
first to use a symbole of zero .The decimal system
depends on the position of each digit .
Ten was taken as the basis of the system because men
used to count on their fingers . Not all ancient peoples
used a decimal system , however , and there are still
some primitive tribes who can count no further than three
. Even the Romans , who were so advanced in many ways
, were poor mathematicians . They were held back by
their inefficient system of writing numbers , which
included no symbol for zero .

*Have you ever used one of these ?
In these days of pocket computers , manual aids to
calculating like abacus seem slow and dated . Yet it is still
use in many parts of the world , notably in China .Many
mechanical calculating machines have been produced
since Pascal , the French mathematician , made his in
1642 , but the great breakthrough did not come until the
1940s when the first electronic computer was made .

*Why is the decimal system not suitable for
computers ?
The circuits in n electronic computer can either be on or
off , according to the impulse they receive . Thus a binary
, or ‘two-based’ , system of counting is needed to suit the
on/off pulses .This is why binary mathematics is now
taught in many schools .

*What is inside a computer ?
 Mistakes in bank accounts , railway bookings and tax
calculations are frequently blamed on computers . people
now have a machine to blame , but , in fact , computers
very seldom make mistakes and a human error in
programming and presenting the information is a much
more likely source . The compuer consists of an input unit
, control unit , output unit , memory unit and arithmetic
unit .
The input unit ‘digests’ the program as it is received and
passes it on to the store in the form of a magnetic
recordings . The store can supply information , or data , a
either to the arithmetic unit , the control unit or directly to
the output unit , as it is needed . All the calculations are
done in the arithmetic unit . The control unit , which is the
‘nerve centre, of the computer , carries out the
instructions which are received in a program . The
arithmetic unit and the control unit each have small stores
of information called registers . The output unit presents
the results of each computer operation , usually as a
printout .
Digital computers are really counting machines . You use
them for high speed mathematical calculations . You can
mutiply , divide , add , or subtract numbers with them .
You can operate the smaller ones manually like
typewriters . Your programme larger digital computers
with punched cards , punched tape or magnetic tape . A
unit called the reader reads the information which
someone puts in .
In this unit , something converts the data into a form
which the computer can use . Someone bases these
computers on very complex electrical circuits .

								
To top