Gbs

1. Information Technology
For Managers
Jithesh B
People Institute of Management Studies Munnad

2. INTRODUCTION
A computer is an electronic machine, operating under the control of instructions
stored in its own memory, that can accept data, manipulate the data according to
specified rules, produce results, and store the results for future use.
Computers processes data to create information.
Data is a collection of raw unprocessed facts, figures, and symbols.
Information is data that is organized, meaningful, and useful.
To process data into information, a computer uses hardware and software.
Hardware is the electric, electronic, and mechanical equipment that makes up a
computer.
Software is the series of instructions that tells the hardware how to perform tasks.

3. HISTORY OF COMPUTER
Charles Babbage, credited deservedly as Father of the Computer, the world
renowned inventor of Differential Engine and Analytical Engine, was born
on the 26th of December, 1791.
In 1822, he designed and built a model called Difference Engine. His
invention could perform calculations without human intervention.
After that, in 1833, Babbage designed a machine called Analytic Engine.
Technology of the analytic engine provided base to the technology of modern
computers. The Analytic Engine had an arithmetic unit to performcalculations
and mechanism to store results and instructions.

4. CHARACTERISTICS OF A COMPUTER
SPEED
ACCURACY
STORAGE
VERSITALITY
DILIGENCE

5. Speed
You will be surprised to know that computer can perform millions (1,000,000) of
instructions and even more per second. Therefore, we determine the speed of computerin
terms of microsecond (10-6 part of a second) or nano-second (10-9 part of a second).
From this you can imagine how fast your computer performs work.
Accuracy
The degree of accuracy of computer is very high and every calculation is performed with
the same accuracy. The accuracy level is determined on the basis of design of computer.
The errors in computer are due to human and inaccurate data.
Diligence
A computer is free from tiredness, lack of concentration, fatigue, etc. It can work for
hours without creating any error. If millions of calculations are to be performed, a
computer will perform every calculation with the same accuracy. Due to this capability it
overpowers human being in routine type of work.

6. Versatility
It means the capacity to perform completely different type of
work. You may use your computer to prepare payroll slips.
Next moment you may use it for inventory management or to
prepare electric bills.
Storage
The Computer has an in-built memory where it can store a
large amount of data. You can also store data in secondary
storage devices such as floppies, which can be kept outside
your computer and can be carried to other computers.

7. DISADVANTAGES OF A COMPUTER
NO IQ
NO
HEURISTICS
NO FEELINGS

8. GENERATIONS OF A COMPUTER
First Generation
(1940-1956)
Vacuum Tubes
Second Generation
(1956-1963)
Transistors
Third Generation
(1964-1971)
Integrated Circuits
Fourth Generation
(1971-Present)
Microprocessors
Fifth Generation
(Present and
Beyond)Artificial
Intelligence

9. FIRST GENRATION (1940-1959)
ENIAC (Electronic Numeric Integrated And Calculator) was the
world first successful electronic computer
developed by the two scientists namely J. P
.Eckert and J. W.
Mauchly.
very huge and big computer and its weight was 30 tones
It could store only limited or small amount of information.
Initially in the first generation computer the concept of vacuum
tubes was used.
had very less work efficiency and so it could not work properly
required a large cooling system.

10. Limitations of First Generation Computer
Followings are the major drawbacks of First
generation computers.
1. The operating speed was quite slow.
2. Power consumption was very high.
3. It required large space for installation.
4. The programming capability was quite low.

11. SECOND GENERATION (1956-1963)
 transistors were used as the electronic component instead of
vaccum tubes
 smaller in the size
 As the size of electrons components decreased from vaccum tube of
transistor, the size of computer also decreased and it became much
smaller than that of earlier computer.
 Some of the computers of the Second Generation were
1.IBM 1620: Its size was smaller as compared to First Generation
computers and mostly used for scientific purpose.
2.IBM 1401: Its size was small to medium and used for business
applications.
3. CDC 3600: Its size was large and is used for scientific purposes.

12. THIRD GENERATION (1964-1971)
first developed by T
.S Kilby
invented in the year 1964.
IC (Integrated circuits) was used as the electronic component for computers
small size, superior performance and reliability than the previous circuits
huge storage capacity and higher calculating speed
FOURTH GENERATION (1971-Present)
This is the generation where we are working today. The computers which we see around
us belong to the fourth generation computers.
‘Micro processor’ is the main concept behind this generation of computer.
A microprocessor is a single chip (L.S.I circuit), which is used in a computer for any
arithmetical or logical functions to be performed in any program.
Developed by Ted Hoff of U.S.A.
He developed first micro-processor, the Intel 4004, as he was working for Intel
Corporation, U.S.A with the use of microprocessor in the fourth generation computers, the
size of computer became very small and it became more efficient.

13. Fifth Generation (Present and Beyond) Artificial
Intelligence
based on artificial intelligence and are still in development
though there are some applications, such as voice
recognition, that are being used today.
goal is to develop devices that respond to natural language
input and are capable of learning and self-organization.

14. FUNCTIONS OF A COMPUTER

15. INPUT: Receiving information from outside sources is the main function of input.
The most common way of performing this function is through the information
entered through the keyboard and the click of mouse. Of course there are many
other sources available which are web cam, scanner, microphone etc.
STORAGE: The main purpose of storage function is to store information and data
in the computer. It is mainly of two types primary memory and secondary
memory. Here primary memory has limited capacity ,as it holds only those data
and instructions on which computer is currently working. Data gets lost as soon
as the computer is switched off . Whereas, secondary memory or external
memory is slower than primary memory .These are use to store data or
information permanently. Once stored can not be erased even if the power is
switched off . Contents of secondary memory are first transferred to main
memory and than CPU can access it.

16. PROCESSING : When a computer receives data from input
device the data must go through an intermediate stage
before it can be sent to an output device, like a monitor,
speaker etc. Therefore this function handles the
intermediate stage being responsible for controlling the
storage and retrieval of data .
OUTPUT : It receives output from a computer in binary
coded form and converts it into human understandable
language. Finally the data is received by the user in desired
format say printer, speaker, monitor etc.

17. TYPES OF COMPUTERS
Digital Computer Analog Computer Hybrid Computer
MICROCOMPUTER
MAINFRAME
MINICOMPUTER
SUPERCOMPUTER

18. Digital Computer
The definition of a digital computer is the most commonly
used type of computer and is used to process information
with quantities using digits, usually using the binary number
system. An example of a digital computer is a MacBook.
noun
“A computer that performs calculations and logical operations
with quantities represented as digits, usually in the binary
number system.”

19. Analog computer
Analog computer is that computer, which is use to process
continuously varying data. Everything we see and hear is
change continuously. ... Examples of analog computer are
temperature, pressure, telephone lines, Speedometer,
resistance of capacitor, frequency of signal and voltage etc

20. Hybrid computers
Hybrid computers are computers that exhibit features of
analog computers and digital computers. The digital
component normally serves as the controller and provides
logical and numerical operations, while the analog
component often serves as a solver of differential equations
and other mathematically complex equations.

21. Microcomputer:
Microcomputer is at the lowest end of the computer range in terms
of speed and storage capacity. Its CPU is a microprocessor.
The first microcomputers were built of 8-bit microprocessor chips.
The most common application of personal computers (PC) is in this
category.
The PC supports a number of input and output devices.An
improvement of 8-bit chip is 16-bit and 32-bit chips.
Examples of microcomputer are IBM PC, PC-AT .

22. Mini Computer:
This is designed to support more than one user at a time.
It possesses large storage capacity and operates at a higher speed.
The mini computer is used in multi-user system in which various users can work at the same
time.
This type of computer is generally used for processing large volume of data in an
organisation.
They are also used as servers in Local Area Networks (LAN).
Mainframes:
These types of computers are generally 32-bit microprocessors.
They operate at very high speed, have very large storage capacity and can handle the work
load of many users.
They are generally used in centralised databases.
They are also used as controlling nodes in Wide Area Networks (WAN).
Example of mainframes are DEC, ICL and IBM 3000 series.

23. Supercomputer:
They are the fastest and most expensive machines.
They have high processing speed compared to other computers.
They have also multiprocessing technique.
One of the ways in which supercomputers are built is by interconnecting
hundreds of microprocessors.
Supercomputers are mainly being used for whether forecasting,
biomedical research, remote sensing, aircraft design and other areas of
science and technology.
Examples of supercomputers are CRAY YMP and PARAM from India.

24. ARCHITECTURE OF A COMPUTER

25. Input: This is the process of entering data and programs in to the computer
system. You should know that computer is an electronic machine like any other
machine which takes as inputs raw data and performs some processing giving
out processed data. Therefore, the input unit takes data from us to the
computer in an organized manner for processing.
Storage: The process of saving data and instructions permanently is known as
storage. Data has to be fed into the system before the actual processing starts.
It is because the processing speed of Central Processing Unit (CPU) is so fast
that the data has to be provided to CPU with the same speed. Therefore the
data is first stored in the storage unit for faster access and processing. This
storage unit or the primary storage of the computer system is designed to do
the above functionality. It provides space for storing data and instructions. The
storage unit performs the following major functions:
All data and instructions are stored here before and after processing.
Intermediate results of processing are also stored here.

26. Processing: The task of performing operations like arithmetic and logical
operations is called processing. The Central Processing Unit (CPU) takes data
and instructions from the storage unit and makes all sorts of calculations
based on the instructions given and the type of data provided. It is then sent
back to the storage unit.
Output: This is the process of producing results from the data for getting
useful information. Similarly the output produced by the computer after
processing must also be kept somewhere inside the computer before being
given to you in human readable form. Again the output is also storedinside
the computer for further processing.
Control: The manner how instructions are executed and the above
operations are performed. Controlling of all operations like input, processing
and output are performed by control unit. It takes care of step by step
processing of all operations in side the computer.