Fundamentals of Computers & Information System

FUNDAMENTALS
OF COMPUTERS & INFORMATION
SYSTEM
HITESH SRIVASTAVA
UNIT - I

Indexing
Content Slide No.
COMPUTER DIFINITION 3
Definition of DATA & Information 4
Features of computer 5-6
BLOCK DIAGRAM 7
Units of computer 8-11
History of Computer 12-18
Computer Hierarchy 19-24
Generations of computer 25-32
Input devices 33-39
Output Device 40-44
Storage Device 45-53

COMPUTER DIFINITION
“ It is a high speed electronic device which
is capable of performing logical and
arithmetical operations . it accepts data as
an input from the user, processes and
gives desirable output ”

DATA- DATA are a set of related facts, the new
material of information data represented by
symbols, but they are not information except in a
limited sense.
INFORMATION- The analyzed data details is
termed ad INFORMATION.

Features of computer
Most of people know that a computer is fast calculator . But it is much more
than that , some of features that make a computer so important are its :-
Speed :- The first feature of computer is speed . It is a very fast device which
can perform any type of task in fraction of seconds. When performing a
particular task for hours together, it can maintain the same speed till the end
of it .
Accuracy :- The word accuracy means exactness of result . Computers can
do the calculations without errors and very accurately.
Versatility:- A computer can perform almost any type of arithmetical and
logical operations

Automation :- A computer can perform a particular work
continuous for hours together without any user ( human )
intervention .
Diligence :- A computer does not suffer from human trait or
tiredness or board . If 3 million calculation has to be performed , it
will perform the 3rd millionth calculation with the same speed and
accuracy as the first one .

BLOCK DIAGRAM
A L U.
M U
C U
OUTPUT
Memory cell
SYSTEM UNIT
INPUT UNIT OUTPUT UNIT

Units of computer
1. INPUT UNIT
it is a device which is used in transferring the data or instruction
to the computer system . Most commonly used input device are
keyboard , mouse , card reader, magnetic disk .
2. SYSTEM UNIT
it is regarded as the brain of the computer . The major
structural components of C.P.U. are –
 Control Unit[CU]
 Arithmetical And Logical Unit[ALU]
 Memory Unit [MU]

Control Unit[CU]
Control unit device directs and coordinates the activities of the entire
computer which includes controlling the input/output devices or units
,the operation of ALU and the transfer data to main memory . An
important function of C.U is program execution , fetching an
instruction from memory , decoding it and sending it to an
appropriate place in the computer to get it executed .

Arithmetical And Logical Unit[ALU]
The arithmetic logical operation unit performs arithmetic operation, the
operands are brought to ALU from the memory . In ALU the required
operation is done and the result is sent back to memory for storage ALU .
All these happens under the control unit . ALU also perform comparison
which are called logical operation, these occurs when the operation are
connected with logical operation .
LOGICAL OPERATION SYMBOL
EQUAL TO =
LESS THAN <
GREATOR THAN >

Output unit
The data passed through the C.P.U can be viewed with the
help of output device ,the monitor or (VDU) of a PC is an
output device.

History of Computer
The discovery of numbers, which is considered as the
greatest achievement of mankind led to the development of
all kinds of calculating device . Today we can’t imagine a
work without numbers , it took thousands of years to get
the present system of numbers .
The stone age man used pebbles for counting people or
animals , stone was replaced by sticks on the rope

The Abacus
clay
board
beads
wire
The earliest and the simplest device that was used for calculations was the
ABACUS , simple abacus has been in use since 3000 B.C.
Abacus was first developed in china and later its use spread to all parts of
the world .

Napier’s “logs” and “bones”
The next manual calculating device logarithms was invented by john
Napier . The use of logarithms enabled him to transform multiplication
and division problems of addition and subtraction . The word logarithms
is a combination of two Greek words , logos (means ratio) and arithms
(means numbers ).

Pascal adding machine
The first mechanical adding machine was invented by BLAISE PASCAL
in 1642 .

Jacquard’s loom
Joseph jacquard initiated actual development
in the early 19th century . Jacquard was a
textile manufacturer he invented automated
loom in 1804 . He used punched card to
produce complex cloth pattern with
automated loom .

Charles Babbage
Charles Babbage , a nineteenth
century professor at Cambridge
university is considered to be father
of modern digital computer . He
designed his “different engine” in
1822 and his “analytical engine” in
1833 .

Hollerith’s machine
In 1855 , Herman Hollerith ,
developed a machine run on the
electricity for the first time for
calculating and recording data .
It was capable of reading both
numbers and letters , processing
and giving out letters and
numbers in designed form .

Computer
Software
Application
Software
MS-Office
Media Player
System
Software
Operating
System
CUI MS-DOS
GUI WINDOWS
Language
Translator
INTEPRETOR
COMPILER
Utility
BIOS
Hardware
INPUT
DEVICE
KEYBOARD
MOUSE
OUTPUT
DEVICE
MONITOR
PRINTER

Important terms :
Software
The set of series of instructions given by the user is known as a
program. All the computer programs written in any programming
languages are collectively known as software.
Application Software
Application software are the software that are designed to satisfy a
particular need of a particular environment.
System Software
The system software is a collection of programs designed to operate,
control and extend the processing capabilities of the computer itself.
It can be further classified into three parts-
(a) Language translator (b) Operating system (c) Utility

(a) Language translator
A software that convert source codes into machines code vice-versa are called
language translator.
Interpreter- A interpreter is an program written in machine level language
whose function is to translate the high level language program into the machine
level language. An interpreter first reads each lines of the program and convert
them from source code. If it find the line error free it executes and then the process
continues till the end of the program. i.e. It will check the program line by line.
Compiler- It is a program machine level language whose function is to translate
the high level language into machine level program. Its usually completes the
whole program from first to last line before attempting to link and run the
program. i.e. compiler will check a program at a time and display all the errors.
Assembler- A assembler is program written in assembly level language whose
functions is to translate the assembly level program into machine level language.

Operating System-
A set of computer programs that manage the hardware and software
resources of a computer system. A set of computer programs that
manage the hardware and software resources of a computer system. At
the foundation of all system software, an operating system performs
basic tasks such as controlling and allocating memory, prioritizing
system requests, controlling input and output devices, facilitating
networking, and managing file systems. Most operating systems have a
command line interpreter as a basic user interface, but they may also
provide a graphical user interface (GUI) for ease of operation. The
operating system forms a platform for other system software and for
application software

Fundamentals of Computers & Information System

Operating System Functions
Here are some of the most common tasks that were done by operating System.
Process Management – Every program running on a computer is a
process. In general, a CPU can only run one process at a time. The operating
system will monitor requested processes and execute them in a pre-designed
order often switching between them very quickly in a way called multi-tasking.
Memory Management – The operating system’s memory manager
coordinates the various types of memory use by tracking which one is available
at any given time. It will also monitor which type of memory can be allocated
or de-allocated and how to move data between the memories.
Disk and File Systems – The way an operating system reads different kinds
of file system as well as file storage. Some operating systems read file names as
case sensitive, while others disregard this.

Security – All operating systems come with some type of security
already built in. Because access to a computer and its often
privileged information should be restricted to only authorize users,
this aspect of an operating system might actually be its most
important function.
Networking – In the Internet age, networking capabilities of
operating systems are very important. Networking capabilities can
be either with an outside computer as in accessing the Internet or
computer to computer as in a large mainframe operation. The
operating system will coordinate all of this below the surface
without the user even being aware it is happening.

CLASSIFICATION OF OPERATING SYSTEM
SINGLE USER OPERATING SYSTEM - A single user operating system will
permit one application program or one task to be run at a time where the
processor (cpu) of a computer does one job at a time it is called a single user
operating system. Ex- Ms-Dos.
MULTI-USER OPERATING SYSTEM - A multi-user operating system will
permit numbers of users to work on the computer system at the same time. Ex-
Linux, Unix.
GRAPHICAL USER INTERPHASE (GUI) OPERATING SYSTEM - A GUI is
uses icons or small images to represent program features instead of typing or
interring the command. This enjoinment is responsible for interacting with users
through icons or pictures. Ex- Windows 95,98,2000 etc.
VERTUAL MEMORY OPERATING SYSTEM - The virtual memory operating
system was originally derived, when the program that went too large to fit in
primary memory. i.e. RAM.A virtual storage operating system will permit data to
moved between primary and secondary as and when the primary storage proves
to be small.

(c) UTILITY PROGRM
These are the programs pre-written by the manufacturers
and supplied with the hardware.
Ex- Text Editor, Sorting, Formatting etc,BIOS.

Generations of computer
The term generation refers to major development in
electronic data processing . Computer technology has been
aimed at making smaller cheaper and efficient computers.
The development of computer has been very rapidly in last
fifty years . It has been in five distinct stages . Each of these
stage is called generation .

First generation (1946-1955)
The first generation computer
is based on the vacuum tube
technology . In the first
generation some important
computers that were designed
are as follows :

 ENIAC (electronic numerical and calculator ) :-
In 1946, Mauchly and Eckert completed the first large scale
electronic digital computer ENIAC . The ENIAC was programmed
by connecting wires between units of the computer and setting
switches at the 50 feet . It was used for , atomic energy calculation
and random numbers studies .
 EDSAC :- After ENIAC was turned off , another computer EDSAC (
electronic delay storage automatic calculator) came in 1943.
EDSAC was first computer to operate on the stored program
concept . It started operating only in 1951 . ENIAC, EDSAC and
other computer which were developed in 1940’s were experimental
basis .
 UNIVAC :- UNIVAC ( universal automatic computer) was the first
computer dedicated to business application . It was also used for
the analysis of 1952 presidential election in united states.

Drawback :
 First generation computer based on vacuum tubes created
several problem
 It generates too much heat .
 It consumed lots of electricity.
 Its, size was large , unreliable and required constant
,maintenance .
 The computer programming language was in binary digit (0,1)
which have a special meaning that can be understood by
computer .
 It was very difficult to write program in machine language ,
moreover most program contained errors and the knowledge
was restricted to few people .

Second generation (1956-1965)
Major innovation was the solid
state device – transistor by three
scientist J.BARDEEN , H.W
BRATTIAN and W.SHOCKLEY in
1947.
A transistor is made of a semi
conductor material whose basic
part is silicon. The size of transistor
is only 1/200th of the size of
vacuum tube
Require much less power and
produce less heat .
Ex : IBM 7094,NCR 304, IBM 1620,
ALTA’S etc .

Third generation (1966-75)
Integrated circuit technology was
introduced around 1965.It is the
combination of numbers of transistors
and other electronic components fused
together on a single crystal. Mass
storage device were called auxiliary or
secondary storage device i.e. magnetic
tape , disk , etc .Multi – programming
software in which more than one can
be present in computer memory
simultaneously .High level language
like basic COBOL, FORTAN , etc , were
developed .A new computer industry
called software industry was born .
Ex: IBM -360, ICL-1900,PDP-8, IBM-
370/168 , etc .

Fourth generation (1976-1985)
A new technology Micro-processors
were introduced . A microprocessor
chip (approx 1/4”*2” in size) contain
an entire central processing units on
single chip .Large scale integration
(L.S.I) and very large scale integration
(V.L.S.I) technology were used in
fourth generation .
Size and cost reduced .
Desktop came into the market .

Fifth generation (1986 onwards)
Ultra large scale technology (U.L.S.I) were introduced
Developed very small but extremely fast and powerful
computers which is known as ROBOTS .
Size were very much reduced .
Small in size and easy to carry out .
Ex: mainframe , super computer , ROBOTS .

Input devices
The device which is used to input information or instruction into the computer
are called input device . Below are given a few input devices:
KEYBOARD:
Allows user to interact directly , it resembles an electronic type writer
keyboard , available in two main category ;
(a) Standard with usually 83-84 keys .
(b) Enhanced or extended with 101 keys .
It is divided into 4 main parts .
1. Main pad.
2. Function key pad .
3. Numeric key pad.
4. Special key pad.

MICR : Magnetic ink character reader is
basically used in banking industry to read
Cheques.
OCR : Optical character reader is
capable of reading any printed or hand
written text they can read at the rate
2400.

OMR : Optical mark reader can
recognize marks made by pencil or ink
on specially designed paper with boxes
which can be marked with a dark
pencil or ink.
BCR: Bar code reader used to
indentify a particular product written
in bar or shops over the product , ex:
books , packages etc .

MOUSE : An electro- mechanical device used
as pointer to select items from an “ on screen”
menu.
SCANNER : The scanner is used to scan
images and store it on the disk as a file , it
can be flat bed or roller feed variety .

LIGHT PEN :
It is a pointing device which can be
used to select an option by simply
printing at it ,or draw figure directly
on the screen and more figures
around .

TOUCH SCREEN :
Normally used when information has to
be assessed with minimum effort , the
screen is made sensitive to touch and
exact position is detected . The screen is
lined with light emitting device ( LED ) .
It is used in hospitals , railways , air
lines , restaurant , stock exchanges , etc .

JOYSTICK :
It is mainly used with computer games ,
and it some times called game controller .
It can be moved left and right (or) up and
down as required to move the
cursor .

Output Device
The input received is processed in the processing
unit and when the result are ready , are given
inform of output . The device through which these
output are given are known as output device .
Below are some commonly used output devices .
MONITORS :-
The most commonly used output device is the
visual display unit (V.D.U ) , which is used to
display information on the screen the V.D.U.
consists of a CRT ( cathode ray tube ) which
produces a beam of electrons that make the
picture on the screen . A VDU normally consist of
25 rows an 80 columns . It has 200 pixels from
top to bottom and 640 pixels from left to right .

Popularly monitors are :
Monochrome :- These types of monitors have single foreground colures and
single background color but have various attribute . Ex; the brightness and
intensity of character which can be changed .
C.G.A ( color graphic adapter ) :- Introduce by IBM in 1982, these monitors
are of low resolution screen (640 row*200 columns) with color capabilities .
H.G.A. ( Hercules graphic adapter ) :- Introduced by Hercules computer
technology in 1982 , these are monochrome adapter with additional graphic
display mode which provide high resolution in graphic mode (750*350 dots )
E.G.A. ( Enhanced graphic ) :- Introduced by I.B.M in 1984 , it was developed
in an effort to unify the variety of display adapter . The E.G.A combines all of the
features of other adapter an d provide high resolution using higher quality color
monitor . It support 16 colors .

V.G.A ( video graphic adapter ) :- Introduced by I.B.M in 1987 , these
monitors support higher resolution and are very expensive . It can support
256 color at a time .
Super V.G.A:- Introduced by a group of American companies in 1988 , it
uses more pixels (56.1) more than V.G.A.

PRINTER :-
A hardware device that produces text or graphics
output on a paper , printer are grouped broadly
into either impact or non-impact
Impact printer :
These printer have mechanical contact with
print medium ( usually paper ) to create an image (
Dot matrix , line printer , daisy wheel printer )
Non – impact printer :
Those printer that not have direct contact with
the print medium fall under this category ( inkjet
printer , laser printer ).

PLOTTER :-
A printer is capable of producing output
that contains printed words . It is capable
of printing straight lines and simple figure
like squares , rectangles and circles . It
require to create high quality visual on
papers , which a printer a printer is not
capable of doing . For this purpose , at
plotter is used .
A plotter is a printer that is used to create
presentation , charts , graphics , maps , and
diagram prepared for statically application
like CAD ( computer added design ) ,
engineering drawing etc .

Primary storage
This memory is directly associated with the C.P.U. before being actually
processing the data , this is to be stored in some storage area . This storage area is
known as primary storage .
It is divided into two distinct parts:-
I. RAM and II. ROM
 RAM :- Random access memory where all data will be stored , while
typing anything it directly stores in electronic circuit and it works
continuously till power continues . It goes through reading procedure from
input device to RAM and it writes from RAM to secondary device like
floppy/ hard disk.

 ROM :- Read only memory basic startup routines and Bios ( basic input output
system ) are permanently loaded during the manufacturing time . It can’t be
altered and fresh information cannot be written into a ROM .
So, if the power is off computer does not lost it’s contents .
It has three parts :
(a) PROM ( programmable read only memory ) :- Once the chip has programmed
the recorded information can’t be changed .
(b) EPROM(erasable programmable read only memory) :- It can be performed or
reprogrammed , usually by exposing a normally covered sector to ultra –violet
light , information can be only “read” and the information remains on the chip
until it is erased .
(c) EEPROM ( electronically erasable programmable ROM ) :- RAM can not store
memory between power interruptions , and hard disk are slow . Enter flash
memory , it does not lose it’s data even if the power is turned off . A flash memory
is used in portable device such as digital camera , voices , recorders and handled
computer .

Cache memory :-
These are small but fast memory logically
positioned between the internal and main memory . It
stores or catches some of the content of the main
memory , currently in use by the processor . Being
nearer to the C.P.U. than the RAM it plays a major role
in the speed and performance of a processor’s (CPU).
To make the processor job easier and quick , the cache
memory stores anticipated instruction . The size of
cache memory being very small . Whenever a CPU
requires data , it checks with the cache and if available
, directly uses the same . Currently PCs normally
features two of cache , L1 or primary cache located in
the CPU itself and L2 or secondary cache located on
system ‘s motherboard .
CPU
CACHE
MAIN MEMORY

Secondary storage device
For permanent storage of data , secondary device can be used with a p.c. system .
Secondary storage is also referred to as external storage .
(A) MAGNETIC TAPES: These storage device are used to keep back-up copies of
previous software and data .

FLOPPY DISK : IT was developed in 1970’s as a cheaper and faster
storage device .it is small random access disk .

HARD DISK : Another magnetic media
suitable for strong large volume of
information is the hard disk . A hard disk
pack contains two or more magnetic
plates fixed to a spindles one below the
other with a set of read/write heads

D) CD-ROM :- Compact disk read only
memory is an optical storage medium
capable of holding up to 660 MB data (
approx 500,000) range of text about 70
minute of high fidelity audio or a
combination of the two

(E) ZIP DRIVE : A zip drive ,
which used a removable disk
cartridge , can be used for backups .
It can typically stores 100 MB or
move on each removable cartridge .
The advantage of this device is that
it is random access just like a disk
drive .

(F) DVD- ROM : THE CD-ROM is
going to obsolete very soon after
arrival of DVD-ROM in the market
for DC-users , it has several time
higher speed and capacity of CD-
ROM very soon . It will be counted
as most common device name CD-
ROM . The full form of DVD-ROM
is Digital video disk read only
memory .

MIS Introduction
The MIS has more than one definition, some of which are given below:
 The MIS is defined as the system that provides information support for
decision making in the organization.
 The MIS is defined as an integrated system of man and machine for
providing the information to support the operations, the management and
the decision making function in the organization.
 The MIS is defines as the system based on the data base of the organization
evolved for the purpose of providing information to the people in the
organization.
 The MIS is defines as a Computer-based Information System.

Data versus Information
To make good decisions, accurate data can be transformed into
information.
Information Processing Cycle:
Input ---> Process ---> Output ---> Storage
(Data) (Information)

Information System
A set of interrelated components that collect (or retrieve),
process, store, and distribute information to support decision
making and control in an organization.
The Difference Between IS and MIS
IS refers to the information system required to run the day-to-
day internal operations of a company. MIS refers to the
information system responsible for securing both internal and
external data that management can use to make operational
decisions. Such decisions may lead to the design of a new
product or service, which is different from the IS required to run
the day-to-day internal operations.

MIS Classification
 Operations Support System (OSS)
 Management Support System(MSS),
 Transaction Processing System(TPS),
 Process Control System(PCS)
 Enterprise Collaboration System(ECS)
 Management Information System(MIS),
 Decision Support System(DSS).

Operations Support System (OSS)
An operational support system (OSS) is a group of computer
programs or an IT system used by communications service
providers for monitoring, controlling, analyzing and managing
a computer or telephone network system. OSS software is
specifically dedicated to telecommunications service providers
and mainly used for supporting network processes to maintain
network inventory, configure network components, provision
services and manage faults.
With the growth of new broadband and Voice over Internet
Protocol (VoIP) systems, OSS and network management are
now applied to home networks.
An OSS is also known as a business support system (BSS).

Management Support System(MSS),
Management Support Systems (MSS) are computer based
systems that are supposed to provide information to be used by
or at least to support managerial decision making.
Management Support Systems is seen as a subset of
management information system (MIS),
Which extends the information retrieval capabilities of the end-
users with ‘query and analysis functions' for searching a
database, generating ‘what if’' scenarios, and other such
purposes. Thus they are collection of all advanced computer
technologies for supporting solutions of managerial problems.
Sometimes called Decision Support Systems or Business
Intelligence but there are some distinctions

Transaction Processing
Transaction processing is a style of computing that divides work into
individual, indivisible operations, called transactions. A transaction
processing system (TPS) or transaction server is a software system, or
software/hardware combination, that supports transaction
processing.
An informational scheme for the collection, storage, retrieval and
modification of transactions made by an organization. An example of
a transaction processing system commonly used in business are the
systems employed by major credit card companies found in almost
every retail store.

Process Control System(PCS)
Process-control system monitors a manufacturing
environment and electronically controls the process or
manufacturing flow based on limits set by the user.
Activities involved in ensuring a process is predictable,
stable, and consistently operating at the target level of
performance with only normal variation.

Enterprise Collaboration System(ECS)
ECS is a combination of Internet, extranets and other networks
needed to support enterprise-wide communications, such as the
sharing of documents and knowledge to specific teams and
individuals within the enterprise.
examples of enterprise communication tools-
 e-mail
 videoconferencing
 collaborative document sharing
 project management tools
The objective of an ECS is to provide each user with the tools
for managing communications, documents and other
information that individuals need to manage their own tasks
efficiently in their departments.

Management Information System(MIS),
A management information system (MIS)
provides information that organizations require
to manage themselves efficiently and effectively.

Decision Support System (DSS)
A Decision Support System (DSS) is a computer-based
information system that supports business or
organizational decision-making activities. DSSs serve the
management, operations, and planning levels of an
organization (usually mid and higher management) and
help to make decisions, which may be rapidly changing
and not easily specified in advance (Unstructured and
Semi-Structured decision problems). Decision support
systems can be either fully computerized, human or a
combination of both

Artificial intelligence
Artificial Intelligence (AI) is an advance branch of science
that studies the process of human thinking and attempts to
apply the knowledge to simulate the same process in
machines.
AI is considered to be the branch of Computer Science than
that of General Science
AI is practically applied in the field of computer games,
expert systems, neural networks, robotics and many other
fields of science and technology

Neural Network
An Artificial Neural Network (ANN) is an information
processing paradigm that is inspired by the way biological
nervous systems, such as the brain, process information.
The key element of this paradigm is the novel structure of
the information processing system. It is composed of a
large number of highly interconnected processing
elements (neurons) working in unison to solve specific
problems. ANNs, like people, learn by example. An ANN is
configured for a specific application, such as pattern
recognition or data classification, through a learning
process

Fuzzy Logic
In recent years, the number and variety of applications of
fuzzy logic have increased significantly. The applications
range from consumer products such as cameras,
camcorders, washing machines, and microwave ovens to
industrial process control, medical instrumentation,
decision-support systems, and portfolio selection.
In a narrow sense, fuzzy logic is a logical system, which is
an extension of multivalve logic.

Fundamentals of Computers & Information System

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Fundamentals of Computers & Information System