Introduction to Computer Systems

Published on November 2016 | Categories: Documents | Downloads: 56 | Comments: 0 | Views: 577
of 3
Download PDF   Embed   Report

Introduction to computer system*Characteristics of a computer*History of computers

Comments

Content

Introduction to Computer Systems
The term Computer is derived from the Latin word compute, which means to
calculate. A computer is an electronic machine, devised for performing calculations and
controlling operations that can be expressed either in logical or numerical terms. In
simple terms, a computer is an electronic device that performs diverse operations with
the help of instructions to process the information in order to achieve the desired results.

Characteristics of Computer
Speed- Computers are capable of carrying out the task with enormous speed. Today’s
computers, according to their class, can perform from 4 MIPS (Millions of instructions per
second) to 100 MIPS.
Storage-Computers can store enormous quantity of information. Which is expressed in
terms of Kilobytes (or) Mega Bytes (MB) or Gega Bytes (GB). It is achieved through its
‘Main memory’ or ‘Primary storage’ and through ‘auxiliary storage’ or ‘Secondary
storage’.
Accuracy- The accuracy of the computer is best achieved by programming them in the
most efficient manner. When it comes to very complex mathematical or scientific
problem the computer’s accuracy has no substitute.
Versatility -Computers are versatile in that they can perform almost any task, provided
they are given the appropriate logical steps.
Automation- The biggest advantage of computers is that it is automatic in its operation.
Once a programming logic is initiated the computer performs repeated operations
without human interventions until program completion.
Diligence-Computers are machines and that do not get tired or ‘lose concentration’ like
human beings.
Reliability- The computers give very accurate results with predetermined values. They
correct and modify the parameters automatically, giving suitable signals. They give
formatted results with high degree of precisions.

History of Computers
Abacus - Abacus was probably the earliest of counting devices. It consists of rectangular
wooden frame with two compartments and beads sliding along the steel wires for
counting.Multiplication and divisions are done using repeated additions and subtractions.
Even today in which cross strings are fixed. Beads are inserted on to the strings. There
are a number of rows of beads.
Napier’s Logs and Bones - John Napier, a Scottish mathematician invented logarithms.
The use of logarithms enabled him to transform multiplications and division problems of
addition and subtractions. In the beginning he called logarithms as artificial numbers.

But later he named them logarithms.Napier also invented a computing device consisting
of sticks with numbers carved on them. These sticks are called bones as they were made
of bones. These bones helped a lot in multiplication involving large numbers.
Slide Rule - As the name indicates, the slide rule has one scale sliding within the other.
Suppose you want to add two numbers 3 and 5, set 3 on the fixed scale and slide the
moving scale. So that its “0’ coincides with”5” of sliding scale. This is the sum of 3 and 5.
The process of reading could be quick if you are trained in the use of slide rule.
Calculating Machines and Pascal’s Calculator - A French mathematician, Blaise
Pascal invented a machine based on gear wheels. He was the son of tax collector who
had to do lot of calculations as part of his job. Blaise Pascal wanted to make his job
easier by inventing a calculator.Pascal provided dials, which indicated numbers stored on
each wheel. He also used suitable “dialing system” to operate the gear wheels.
Babbage difference and analytical engines - Babbage, a British National and the son
of a wealthy banker wanted to correct the errors in the logarithm tables being used
during his time. In 1822, he made a machine which calculated the successive difference
of expressions and prepared table which helped him in his calculations. The royal
Astronomical society awarded a gold medal to him for his invention and granted a large
sum of money to carry out further work.
Lady Ada Lovelace - Lovelace is the daughter of the famous English poet Lord Byron.
She was a mathematician. She studied the works of Babbage and wrote about them.
From her account only, we can see the close resemblance of the modern day computers
and Babbage’s work. Lady Ada Lovelace’s contributions are very important. Since she
predicted that computers can be programmed, a language, Ada used widely in America’s
Department of Defense Computers was named after her.
Herman Hollerith’s Machine - Dr. Herman Hollerith Produced cards out of special
paper pulp, designed punching machines to punch holes in the card to count census
figures and invented sorting machines to read such punched card and collect data. He
could complete the job within three years, achieving a speedup of about three times.
ABC Computer - In 1937, Dr. John Atanstoff with the help of his assistant Berry
designed the Atanstoff Berry Computer (ABC). The machine laid the foundation for the
development of electronic digital computer.
ENIAC- Electronic Numerical Integrator and Calculator - In 1947 john Mauchly and
Eckart completed the first large scale Electronic Digital Computer, ENIAC. In this
computer, each time a program was changed, the wiring had to be completely
rearranged. It weighed 30 tons, contained 18,000 vacuum tubes and occupied a space of
30 to 50 feet.
EDSAC-Electronic Delay Storage Automatic Calculator - Maurice V. Wilkes of
Cambridge University completed EDSAC in 1949. EDSAC was the first computer to
operate on the stored program concept.

UNIVAC-I – Universal Automatic Computers - In 1947, after ENIAC became
operational Mauchly and Eckart formed their own Company- The Eckart-Mauchly
Computer Corporation”. Immediately after this they started the design of UNIVAC-I. This
was purchased by US bureau of Census. UNIVAC was the first computer dedicated to
business applications.

Sponsor Documents

Or use your account on DocShare.tips

Hide

Forgot your password?

Or register your new account on DocShare.tips

Hide

Lost your password? Please enter your email address. You will receive a link to create a new password.

Back to log-in

Close