BCom II FUNDAMENTAL OF COMPUTER

FUNDAMENTALS OF COMPUTER
B.Com–II sem.
INTRODUCTION TO COMPUTERS
(UNIT I)
⇒DEFINITION
Computer System is an electronic and programmable device which does the following:
•
•
•
Accept and store an input data.
Process the data input.
And output the processed data in required format.
Versatility
• A computer is a very versatile machine.
• A computer is very flexible in performing the jobs to be done.
• This machine can be used to solve the problems relating to various different fields.
• At one instant, it may be solving a complex scientific problem and the very next moment it
may be playing a card game.
Reliability
• A computer is a reliable machine.
• Modern electronic components have failure free long lives.
• Computers are designed to make maintenance easy.
⇒ADVANTAGES OR CHARACTERISTICS
Automation
• Computer is a automatic machine.
• Automation means ability to perform the task automatically.
• Once a program is given to computer i.e stored in computer memory, the program and
instruction can control the program execution without human interaction.
Following list demonstrates the advantages of Computers in today's arena.
Reduction in Paper Work
•
High Speed
• Computer is a very fast device.
• It is capable of performing addition of very big data.
• The computer has units of speed in microsecond, nanosecond and even the picoseconds.
• It can perform millions of calculations in a few seconds as compared to man who can spend
many months for doing the same task.
•
The use of computers for data processing in an organization leads to reduction in paper
work and speeds up the process.
As data in electronic files can be retrieved as and when required,the problem of
maintenance of large number of files gets reduced.
Reduction in Cost
•
Though the initial investment for installing a computer is high but it substantially reduces
the cost of each of its transaction.
Accuracy
•
•
•
In addition to being very fast, computer are very accurate.
The computer has performed calculations 100% error free.
Computers perform all jobs with 100% accuracy.
⇒DISADVANTAGES
Following list demonstrates the disadvantages of Computers in today's arena.
Storage Capability
•
•
•
•
Diligence
•
•
•
No I.Q
Memory is a very important characteristic of computers.
The computer has much more storage capacity than human beings.
It can store large amount of data.
It can store any type of data such as images, videos, text, audio and any other type.
Unlike human beings, a computer is free from monotony, tiredness and lack of
concentration.
It can work continuously without creating any error and boredom.
It can do repeated work with same speed and accuracy.
Source: Pradeepkumar. K.
•
•
•
A computer is a machine and has no intelligence of its own to perform any task.
Each and every instruction has to be given to computer.
A computer can not take any decision on its own.
Dependency
• It can perform function as instructed by user.So it is fully dependent on human being.
Environment
• The operating environment of computer should be dust free and suitable to it.
No Feeling
• Computer has no feeling or emotions.
WEB SOURCE: www.pradikshana.weebly.com
1
FUNDAMENTALS OF COMPUTER
•
B.Com–II sem.
It cannot make Judgment based on feeling, taste, experience and knowledge unlike a
human being.
•
•
survival benefits
bonus
⇒APPLICATIONS / USES OF COMPUTERS IN TODAY'S..
Education
Business
The computer has provided a lot of facilities in the Education System.
The computer's characteristic as high speed of calculation, diligence, accuracy, reliability, or
versatility has made it an integrated part in all business organizations.
•
•
Computer used in business organization for:
•
•
•
•
•
•
•
•
Payroll Calculations
Budgeting
Sales Analysis
Financial forecasting
Managing employees database
Maintenance of stocks etc.
•
Marketing
In Marketing uses of computer are following:
Banking
•
Today Banking is almost totally dependent on computer.
•
Banks provide following facilities:
•
•
The uses of computer provide a tool in the Education system is known as CBE (Computer
Based Education).
CBE involves Control, Delivery and Evaluation of learning.
The computer education is very familiar and rapidly increasing the graph of computer
students.
There are number of methods in which educational institutions can use computer to educate
the students.
It is used for prepare a database about student performance and analysis are carried out.
Banks on-line accounting facility, which include current balances, deposits, overdrafts,
interest charges, shares and trustee records.
ATM machines are making it even easier for customers to deal with banks.
Insurance
Insurance companies are keeping all records up to date with the help of computer. The Insurance
Companies, Finance houses and Stock broking firms are widely using computers for their concerns.
Advertising: With computers, advertising professionals create art and graphics, write and
revise copy, and print and disseminate ads with the goal of selling more products.
At Home Shopping: At home shopping has been made possible through use of
computerized catalogues that provide access to product information and permit direct entry
of orders to be filled by the customers.
Health Care
Computers have become important part in all Medical Systems.
The computers are being used in hospitals to keep the record of patients and medicines. It is also used
in scanning and diagnosing different diseases. ECG, EEG, Ultrasounds and CT Scans etc. are also
done by computerized machines.
Some of major fields of health care in which computer are used:
Insurance Companies are maintaining a database of all clients with information showing
•
•
•
•
•
how to continue with policies
starting date of the policies
next due installment of a policy
maturity date
interests due
Source: Pradeepkumar. K.
•
•
•
•
•
Diagnostic System: Computers are used to collect data and identify cause of illness.
Lab-diagnostic System: All tests can be done and reports are prepared by computer.
Patient Monitoring System:These are used to check patient's signs for abnormality such
as in Cardiac Arrest, ECG etc.
Pharmacy Information System:Computer checks Drug-Labels, Expiry dates, harmful
drug side effects etc.
Nowadays, computers are also used in performing surgery.
WEB SOURCE: www.pradikshana.weebly.com
2
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
•
•
•
•
•
•
•
Engineering Design
Computers are widely used in Engineering purposes.
One of major areas is CAD(Computer aided design).CAD provides creation, edition, and
modification of image. Some fields are:
•
•
•
Structural Engineering: Requires stress and strain analysis required for design of Ships,
Buildings, Budgets, Airplanes etc.
Industrial Engineering: Computers deals with design, implementation and improvement
of Integrated systems of people, materials and equipments.
Architectural Engineering: Computers help in planning towns, designing buildings,
determining a range of buildings on a site using both 2D and 3D drawings.
Military
Computers are largely used in defence.Modern tanks, missiles, weapons etc.employ computerized
control systems.Some military areas where a computer has been used are:
•
•
•
•
Generation in computer terminology is a change in technology a computer is/was being used.
Initially, the generation term was used to distinguish between varying hardware technologies. But
nowadays, generation includes both hardware and software, which together make up an entire
computer system.
There are totally five computer generations known till date. Each generation has been discussedin
detail along with their time period, characteristics. We've used approximate dates against each
generations which are normally accepted.
S.N.
Communication means to convey a message, an idea, a picture or speech that is received and
understood clearly and correctly by the person for whom it is meant.Some main areas in this category
are:
E-mail
Chatting
Usenet
FTP
Telnet
Video-conferencing
Generation & Description
Term
Technology
1
First Generation
The period of first generation : 1946-1955.
Vaccum tube based.
2
Second Generation
The period of second generation :1956-1965.
Transistor based.
3
Third Generation
The period of third generation : 1966-1975.
Integrated Circuit based.
4
Fourth Generation
The period of fourth generation : 1976-1985. VLSI microprocessor based.
5
Fifth Generation
The period of fifth generation : 1986-onwards.ULSI microprocessor based
⇒First Generation
The period of first generation was 1945-1955.
Government Applications
Computers play an important role in government applications.Some major fields in this category are:
•
⇒ COMPUTER GENERATIONS
Following are the main five generations of computers
Missile Control
Military Communication
Military operation and planning
Smart Weapons
Communication
•
•
•
•
•
•
Sales tax department
Income tax department
Male/Female ratio
Computerization of voters lists
Computerization of Driving Licensing system
Computerization of PAN card
Weather Forecasting.
First generation of computer started with using vacuum tubes as the basic components for memory
and circuitry for CPU(Central Processing Unit). These tubes like electric bulbs produced a lot of heat
and were prone to frequent fusing of the installations, therefore, were very expensive and could be
afforded only by very large organizations.
Budgets
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
3
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
In this generation mainly batch processing operating system were used. In this generation Punched
cards, Paper tape, Magnetic tape Input & Output device were used.
•
•
•
•
There were Machine code and electric wired board languages used.
The main features of First Generation are:
•
•
•
•
•
•
•
•
•
•
•
Vacuum tube technology
Unreliable
Supported Machine language only
Very costly
Generate lot of heat
Slow Input/Output device
Huge size
Need of A.C.
Non portable
Consumed lot of electricity
•
•
•
•
Use of transistors
Reliable as compared to First generation computers
Smaller size as compared to First generation computers
Generate less heat as compared to First generation
computers
Consumed less electricity as compared to First
generation computers
Faster than first generation computers
Still very costly
A.C. needed
Support machine and assembly languages
Some computer of this generation were:
•
•
•
•
•
Some computer of this generation were:
•
•
•
•
•
The main features of Second Generation are:
ENIAC : Electronic Numerical Integrator And Calculator.
EDVAC: Electronic Discreet Variable Automatic Computer.
UNIVAC: UNIVersal Automatic Computer
IBM-701
IBM-650
IBM 1620
IBM 7094
CDC 1604
CDC 3600
UNIVAC 1108
⇒Third Generation
The period of third generation was 1966-1975.
The third generation of computer is marked by the use of Integrated Circuits (IC's) in place of
transistors. A single I.C has many transistors, resistors and capacitors along with the associated
circuitry. The I.C was invented by Jack Kilby. This development made computers smaller in size,
reliable and efficient.
⇒Second Generation
The period of second generation was 1956-1965.
This generation using the transistor were cheaper, consumed less power, more compact in size, more
reliable and faster than the first generation machines made of vaccum tubes.In this generation,
magnetic cores were used as primary memory and magnetic tape and magnetic disks as secondary
storage devices.
In this generation assembly language and high level programming language like FORTRAN,
COBOL were used.
In this generation Remote processing, Time-sharing, Real-time, Multi-programming Operating
System were used.
High level language (FORTRAN-II TO IV, COBOL, PASCAL PL/1, BASIC, ALGOL-68 etc.) were
used during this generation.
There were Batch processing and Multiprogramming Operating system used.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
4
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
The main features of Fourth Generation are:
The main features of Third Generation are:
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
IC used
More reliable
Smaller size
Generate less heat
Faster
Lesser maintenance
Still costly
A.C needed
Consumed lesser electricity
Support high level language
Some computer of this generation were:
•
•
•
•
•
VLSI technology used
Very cheap
Portable and reliable
Use of PC's
Very small size
Pipeline processing
No A.C. needed
Concept of internet was introduced
Great developments in the fields of networks
Computers became easily available
Some computer of this generation were:
•
•
•
•
•
IBM-360 series
Honeywell-6000 series
PDP(Personal Data Processor)
IBM-370/168
TDC-316
DEC 10
STAR 1000
PDP 11
CRAY-1(Super Computer)
CRAY-X-MP(Super Computer)
⇒Fourth Generation
⇒Fifth Generation
The period of Fourth Generation was 1976-1985.
The period of Fifth Generation is 1986-till date.
The fourth generation of computers is marked by the use of Very Large Scale Integrated (VLSI)
circuits.VLSI circuits having about 5000 transistors and other circuit elements and their associated
circuits on a single chip made it possible to have microcomputers of fourth generation. Fourth
Generation computers became more powerful, compact, reliable, and affordable. As a result, it gave
rise to personal computer (PC) revolution.
In the fifth generation, the VLSI technology became ULSI (Ultra Large Scale Integration)
technology, resulting in the production of microprocessor chips having ten million electronic
components.
In this generation Time sharing, Real time, Networks, Distributed Operating System were used.
AI is an emerging branch in computer science, which interprets means and method of making
computers think like human beings.
This generation is based on parallel processing hardware and AI (Artificial Intelligence) software.
All the Higher level languages like C and C++, DBASE etc. were used in this generation.
All the Higher level languages like C and C++, Java, .Net etc. are used in this generation.
AI includes:
•
•
•
•
Source: Pradeepkumar. K.
Robotics
Neural networks
Game Playing
Development of expert systems to make decisions in real life situations.
WEB SOURCE: www.pradikshana.weebly.com
5
FUNDAMENTALS OF COMPUTER
•
B.Com–II sem.
PC (Personal Computer)
Natural language understanding and generation.
A PC can be defined as a small, relatively inexpensive computer designed for an individual user. PCs
are based on the microprocessor technology that enables manufacturers to put an entire CPU on one
chip. Businesses use personal computers for word processing, accounting, desktop publishing, and
for running spreadsheet and database management applications. At home, the most popular use for
personal computers is for playing games and surfing the Internet.
The main features of Fifth Generation are:
•
•
•
•
•
•
•
ULSI technology
Development of true artificial intelligence
Development of Natural language processing
Advancement in Parallel Processing
Advancement in Superconductor technology
More user friendly interfaces with multimedia features
Availability of very powerful and compact computers at cheaper rates
Although personal computers are designed as single-user systems, these systems are normally linked
together to form a network. In terms of power, now-a-days High-end models of the Macintosh and
PC offer the same computing power and graphics capability as low-end workstations by Sun
Microsystems, Hewlett-Packard, and DELL.
Some computer types of this generation are:
•
•
•
•
•
Desktop
Laptop
NoteBook
UltraBook
ChromeBook
WorkStation
Workstation is a computer used for engineering applications (CAD/CAM), desktop publishing,
software development, and other such types of applications which require a moderate amount of
computing power and relatively high quality graphics capabilities.
⇒Computer can be broadly classified by their speed and computing power.
BASED ON SIZE OR CAPACITY:
Sr. No.
1
2
3
4
5
Type
Specifications
Single user computer system. Moderately powerful
PC (Personal Computer)
microprocessor.
Single user computer system. Similar to Personal Computer but
WorkStation
have more powerful microprocessor.
Multi-user computer system. Capable of supporting hundreds of
Mini Computer
users simulaneously.
Multi-user computer system. Capable of supporting hundreds of
Main Frame
users simulaneously.Software technology is different from
minicomputer.
An extremely fast computer which can perform hundreds of
Supercomputer
millions of instructions per second.
Source: Pradeepkumar. K.
Workstations generally come with a large, high-resolution graphics screen, large amount of RAM,
inbuilt network support, and a graphical user interface. Most workstations also have a mass storage
device such as a disk drive, but a special type of workstation, called a diskless workstation, comes
without a disk drive.
Common operating systems for workstations are UNIX and Windows NT. Like PC, Workstations are
also single-user computers. However, workstations are typically linked together to form a local-area
network, although they can also be used as stand-alone systems.
WEB SOURCE: www.pradikshana.weebly.com
6
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
All types of computer follows a same basic logical structure and perform the following five basic
operations for conve
Minicomputer
It is a midsize computer. A minicomputer is a multi-processing system capable of supporting from up
to 250 users simultaneously.
rting raw input data into information useful to their users
Sr. No.
Operation
1
Take Input
2
Store Data
Mainframe
3
Processing Data
Mainframe is a very large in size and is an expensive computer capable of supporting hundreds, or
even thousands, of users simultaneously. Mainframe executes many programs concurrently.
Mainframes support many simultaneous programs execution.
4
Output Information
5
Control the workflow
Description
The process of entering data and instructions into the computer
system.
Saving data and instructions so that they are available for
processing as and when required.
Performing arithmetic , logical operations on data in order to
convert them into useful information.
The process of producing useful information or results for the
user,such as a printed report or visual display.
Direct the manner and sequence in which all of the above
operations are performed
BLOCK DIAGRAM(or STRUCTURE) OF COMPUTER
CPU
CONTROL
UNIT
Supercomputer
ARITHMATIC &
LOGIC
UNIT
Supercomputers are one of the fastest computers currently
available. Supercomputers are very expensive and are employed
for specialized applications that require immense amounts of
mathematical calculations (number crunching). For example, weather forecasting , scientific
simulations, (animated) graphics, fluid dynamic calculations, nuclear energy research, electronic
design, and analysis of geological data (e.g. in petrochemical prospecting).
INPUT
DIVICE
OUTPUT
DEVICE
MAIN MEMORY
SECONDARY
MEMORY
BASED ON DATA HANDLING TECHNIQUE
1) ANALOG COMPUTER: these works on “continuos data” which may be
temperature, or some other measurement units.
2) DIGITAL COMPUTER: which works on “descrete data”, such as digital formed
numbers, letters etc.
3) HYBRID COMPUTER: These include features of both ANALOG & DIGITAL
computer.
BASIC OPERATION OF COMPUTER:
Source: Pradeepkumar. K.
DATA
SYSTEM UNIT
Input Unit
This unit contains devices with the help of which we enter data into computer.This unit makes link
between user and computer.
The input devices translate the human being information into the form understandable by computer.
WEB SOURCE: www.pradikshana.weebly.com
7
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
CPU (Central Processing Unit)
CPU is considered as the brain of the computer. CPU perform all types of data processing operations.
It stores data , intermediate results and instructions(program).It controls the operation of all parts of
computer.
This unit can store instruction, data and intermediate results. This unit supplies information to the
other units of the computer when needed. It is also known as internal storage unit or main memory or
primary storage or Random access memory (RAM).
Its size affects speed, power and capability. There are primary memory and secondary memory two
types of memories in the computer. Function of Memory Unit are:
CPU itself has following three components
•
•
•
•
•
•
•
ALU(Arithmetic Logic Unit)
Memory Unit
Control Unit
It stores all the data to be processed and the instructions required for processing.
It stores intermediate results of processing.
It stores final results of processing before these results are released to an output device.
All inputs and outputs are transmitted through main memory.
Output Unit
Control Unit
Output unit consists of devices with the help of which we get the information from computer. This
unit is a link between computer and users.
This unit controls the operations of all parts of computer. It does not carry out any actual data
processing operations.
Output devices translate the computer's output into the form understandable by users.
Functions of this unit are
•
•
•
•
CPU is considered as the brain of the computer.
CPU performs all types of data processing operations.
It stores data , intermediate result and instructions(program).
It controls the operation of all parts of computer.
•
•
•
•
•
It is responsible for controlling the transfer of data and instructions among other units of a
computer.
It manages and coordinates all the units of the computer.
It obtains the instructions from the memory, interprets them and directs the operation of the
computer.
It communicates with Input/output devices for transfer of data or results from storage.
It does not process or store data.
ALU(Arithmetic Logic Unit)
This unit consists of two subsection namely
CPU itself has following three components.
•
•
•
Memory Or Storage Unit:
Control Unit
ALU(Arithmetic Logic Unit)
•
•
Arithmetic section
Logic Section
Arithmetic section
Function of Arithmetic section is to perform arithmetic operations like addition, subtraction,
multiplication and division. All complex operations are done by making repetitive use of above
operations.
Memory Or Storage Unit:
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
8
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Logic Section
Function of logic section is to perform logic operations such as comparing, selecting, matching and
merging of data.
5
Special Purpose Keys
directional arrow key.Control keys also include Home,
End,Insert, Delete, Page Up, Page Down, Control(Ctrl),
Alternate(Alt), Escape(Esc).
Keyboard also contains some special purpose keys such as Enter,
Shift, Caps Lock, Num Lock, Space bar, Tab, and Print Screen.
⇒Following are few of the important input devices which are used in
Computer Systems
•
•
•
•
•
•
•
•
•
•
•
•
Keyboard
Mouse
Joy Stick
Light pen
Track Ball
Scanner
Graphic Tablet
Microphone
Magnetic Ink Card Reader(MICR)
Optical Character Reader(OCR)
Bar Code Reader
Optical Mark Reader
Keyboard
Most common and very popular input device is keyboard. The keyboard helps in inputting the data to
the computer. The layout of the keyboard is like that of traditional typewriter, although there are
some additional keys provided for performing some additional functions.
Keyboard is of two sizes 84 keys or 101/102 keys, but now 104 keys or 108 keys keyboard is also
available for Windows and Internet.
Keys
1
Alphabets Keys
2
Numeric Keypad
3
Function Keys
4
Control keys
Source: Pradeepkumar. K.
TYPES OF KEYBOARD
BASED ON KEYS
TECHNOLOGY
STANDARD
KEYBOARD
The keys are following
Sr. No.
TYPES OF KEYBOARD:
Description
These keys include the letter keys (A-Z) and digits keys (0-9)
which are generally give same layout as that of typewriters.
It is used to enter numeric data or cursor movement. Generally, it
consists of a set of 17 keys that are laid out in the same
configuration used by most adding machine and calculators.
BASED ON
CONNECTIVITY
MULTIMEDIA
KEYBOARD
PS/2 KEYBOARD
WIRED
WIRELESS
U.S.B. KEYBOARD
BLUETOOTH
The twelve functions keys are present on the keyboard. These are
arranged in a row along the top of the keyboard.Each function
key has unique meaning and is used for some specific purpose.
These keys provides cursor and screen control. It includes four
WEB SOURCE: www.pradikshana.weebly.com
9
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Mouse
Light Pen
Mouse is most popular Pointing device. It is a very famous cursor-control device. It is a small palm
size box with a round ball at its base which senses the movement of mouse and sends corresponding
signals to CPU on pressing the buttons.
Light pen is a pointing device which is similar to a pen. It is used to select a displayed menu item or
draw pictures on the monitor screen.It consists of a photocell and an optical system placed in a small
tube.
Generally it has two buttons called left and right button and scroll bar is present at the mid. Mouse
can be used to control the position of cursor on screen, but it cannot be used to enter text into the
computer.
When light pen's tip is moved over the monitor screen and pen button is pressed, its photocell sensing
element detects the screen location and sends the corresponding signal to the CPU.
Advantages
•
•
•
Easy to use
Not very expensive
Moves the cursor faster than the arrow keys of keyboard.
Track Ball
Track ball is an input device that is mostly used in notebook or laptop computer, instead of a mouse.
This is a ball which is half inserted and by moving fingers on ball, pointer can be moved.
TYPES OF MOUSE
BASED
TECHNOLOGY
OPTICAL
BASED ON
CONNECTIVITY
MECHANICAL
PS/2 KEYBOARD
WIRED
Since the whole device is not moved, a track ball requires less space than a mouse. A track ball
comes in various shapes like a ball, a button and a square.
WIRELESS
U.S.B. KEYBOARD
BLUETOOTH
Joystick
Joystick is also a pointing device which is used to move cursor position on a monitor screen. It is a
stick having a spherical ball at its both lower and upper ends. The lower spherical ball moves in a
socket.TheJoystic can be moved in all four directions.
The function of joystick is similar to that of a mouse. It is mainly used in Computer Aided Designing
(CAD) and playing computer games.
Scanner
Scanner is an input device which works more like a photocopy machine. It is used when some
information is available on a paper and it is to be transferred to the hard disc of the computer for
further manipulation.
Scanner captures images from the source which are then converted into the digital form that can be
stored on the disc.These images can be edited before they are printed.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
10
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Types: 1) FLAT BED SCANNER
2) SHEET FED SCANNER
3) HANDHELD SCANNER
4) DRUM SCANNER.
Digitizer
Digitizer is an input device which converts analog information into a digital form. Digitizer can
convert a signal from the television camera into a series of numbers that could be stored in a
computer. They can be used by the computer to create a picture of whatever the camera had been
pointed at.
Optical Character Reader(OCR)
OCR is an input device used to read a printed text. OCR scans text optically character by character,
converts them into a machine readable code and stores the text on the system memory.
Digitizer is also known as Tablet or Graphics Tablet because it converts graphics and pictorial data
into binary inputs. A graphic tablet as digitizer is used for doing fine works of drawing and images
manipulation applications.
Bar Code Readers
Microphone
Bar Code Reader is a device used for reading bar coded data (data in form of light and dark lines).
Bar coded data is generally used in labelling goods, numbering the books etc. It may be a hand held
scanner or may be embedded in a stationary scanner.
Microphone is an input device to input sound that is then stored in digital form. The microphone is
used for various applications like adding sound to a multimedia presentation or for mixing music.
Bar Code Reader scans a bar code image, converts it into an alphanumeric value which is then fed to
the computer to which bar code reader is connected.
Magnetic Ink Character Reader(MICR)
MICR input device is generally used in banks because of a large number of cheques to be processed
every day. The bank's code number and cheque number are printed on the cheques with a special type
of ink that contains particles of magnetic material that are machine readable.
This reading process is called Magnetic Ink Character Recognition(MICR). The main advantages of
MICR is that it is fast and less error prone.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
11
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
The most screens are capable of displaying 80 characters of data horizontally and 25 lines vertically.
There are some disadvantage of CRT
Optical Mark Reader(OMR)
OMR is a special type of optical scanner used to recognize the type of mark made by pen or pencil. It
is used where one out of a few alternatives is to be selected and marked. It is specially used for
checking the answer sheets of examinations having multiple choice questions.
•
•
Large in Size
High Power consumption
Flat-Panel Display Monitor
Following are few of the important output devices which are used in Computer Systems
•
•
•
The flat-panel display refers to a class of video devices that have reduced volume, weight and power
requirement compare to the CRT. You can hang them on walls or wear them on your wrists. Current
uses for flat-panel displays include calculators, videogames, monitors, laptop computer, graphics
display.
Monitors
Graphic Plotter
Printer
The flat-panel display are divided into two categories
Monitors
Monitor commonly called as Visual Display Unit (VDU) is the main output device of a computer. It
forms images from tiny dots, called pixels, that are arranged in a rectangular form. The sharpness of
the image depends upon the no. of the pixels.
•
•
There are two kinds of viewing screen used for monitors.
•
•
Emissive Displays - The emissive displays are devices that convert electrical energy into
light. Example are plasma panel and LED(Light-Emitting Diodes).
Non-Emissive Displays - The Non-emissive displays use optical effects to convert sunlight
or light from some other source into graphics patterns.Example is LCD(Liquid-Crystal
Device)
Cathode-Ray Tube (CRT)
Flat- Panel Display
Cathode-Ray Tube (CRT) Monitor
Printers
In the CRT display is made up of small picture elements called pixels for short.The smaller the
pixels, the better the image clarity, or resolution.It takes more than one illuminated pixel to form
whole character, such as the letter e in the word help.
Printer is the most important output device, which is used to print information on paper.
A finite number of character can be displayed on a screen at once.The screen can be divided into a
series of character boxes - fixed location on the screen where a standard character can be placed.
Source: Pradeepkumar. K.
•
•
Impact Printers
Non-Impact Printers
WEB SOURCE: www.pradikshana.weebly.com
12
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Dot Matrix Printer
TYPES OF
PRINTER
SERIAL
IMPACT
SERIAL NONIMPACT
PARELLEL
IMPACT
In the market one of the most popular printer is Dot Matrix Printer because of their ease of printing
features and economical price. Each character printed is in form of pattern of Dot's and head consists
of a Matrix of Pins of size(5*7, 7*9, 9*7 or 9*9) which comes out to form a character that is why it is
called Dot Matrix Printer.
PARELLEL
NON-IMPACT
Advantages
•
•
•
EX: 1) DOT
MATRIX PRINTER
2) DAISY WHEEL
PRINTER
EX: 1) THERMAL
PRINTER
2) ELECTRO
RESISTIVE
EX: 1) CHAIN
PRINTER
2) DRUM
PRINTER
EX: 1) LASER
PRINTER
2) INK JET
PRINTER
Impact Printers
Inexpensive
Widely Used
Other language characters can be printed
Disadvantages
•
•
Slow Speed
Poor Quality
The printers that print the characters by striking against the ribbon and onto the paper, are called
impact printers.
Characteristics of Impact Printers are following
•
•
•
•
Very low consumable costs
Impact printers are very noisy
Useful for bulk printing due to low cost
There is physical contact with the paper to produce an image
These printers are of two types
•
•
Head is lying on a wheel and Pins corresponding to characters are like petals of Daisy(flower name)
that is why it is called Daisy Wheel Printer. These printers are generally used for word-processing in
offices which require a few letters to be send here and there with very nice quality representation.
Advantages
Character printers
Line printers
Character Printers:
Character Printers are printers which print one character at a time.
These are of further two types
•
•
Daisy Wheel
Dot Matrix Printer(DMP)
Daisy Wheel
Source: Pradeepkumar. K.
•
•
•
More reliable than DMP's
Better quality
The fonts of character can be easily changed.
Disadvantages
•
•
•
Slower than DMP's
Noisy
More expensive than DMP's
WEB SOURCE: www.pradikshana.weebly.com
13
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Advantages
•
•
Character fonts can easily be changed.
Different languages can be used with the same printer.
Disadvantages
•
•
Line Printers
Line printers are printers which print one line at a time.
Noisy
Do not have the ability to print any shape of characters.
Non-impact Printers
The printers that print the characters without striking against the ribbon and onto the paper, are called
Non-impact Printers. These printers print a complete page at a time, also called as Page Printers.
These printers are of two types
•
•
These are of further two types
•
•
Drum Printer
Chain Printer
Characteristics of Non-impact Printers
Drum Printer
This printer is like a drum in shape so it called drum printer. The surface of drum is divided into
number of tracks. Total tracks are equal to size of paper i.e for a paper width of 132 characters, Drum
will have 132 tracks. A character set is embossed on track. The different characters sets are available
in market 48 character set, 64 and 96 characters set.One rotation of drum prints one line. Drum
Printers are fast in speed and speed in between 300 to 2000 lines per minute.
Very high speed
Laser Printers
•
•
•
•
Very expensive
Characters fonts can not be changed
Chain Printer: In this printer chain of character sets are used so it called Chain Printers.A standard
character set may have 48, 64, 96 characters.
Source: Pradeepkumar. K.
Faster than impact printers.
They are not noisy.
High quality.
Support many fonts and different character size.
Advantages
Disadvantages
•
•
•
•
•
•
These are non-impact page printers. They use laser lights to produces the dots needed to form the
characters to be printed on a page.
Advantages
•
Laser Printers
Inkjet Printers
Very high speed.
Very high quality output.
Give good graphics quality.
Support many fonts and different character size.
Disadvantage
WEB SOURCE: www.pradikshana.weebly.com
14
FUNDAMENTALS OF COMPUTER
•
•
B.Com–II sem.
The memory is divided into large number of small parts. Each part is called cell. Each location or cell
has a unique address which varies from zero to memory size minus one.
Expensive.
Cannot be used to produce multiple copies of a document in a single printing.
For example if computer has 64k words, then this memory unit has 64 * 1024=65536 memory
location. The address of these locations varies from 0 to 65535.
Memory is primarily of three types
Inkjet Printers
Inkjet printers are non-impact character printers based on a relatively new technology. They print
characters by spraying small drops of ink onto paper. Inkjet printers produce high quality output with
presentable features.
•
•
•
•
Cache Memory
Registers, Flip Flops
Primary Memory/Main Memory
Secondary Memory
Cache Memory
They make less noise because no hammering is done and these have many styles of printing modes
available. Colour printing is also possible. Some models of Inkjet printers can produce multiple
copies of printing also.
Advantages
•
•
Cache memory is a very high speed semiconductor memory which can speed up CPU. It acts as a
buffer between the CPU and main memory.
It is used to hold those parts of data and program which are most frequently used by CPU. The parts
of data and programs are transferred from disk to cache memory by operating system, from where
CPU can access them.
High quality printing
More reliable
Advantage
Disadvantages
•
•
•
•
•
•
Expensive as cost per page is high
Slow as compare to laser printer
Cache memory is faster than main memory.
It consumes less access time as compared to main memory.
It stores the program that can be executed within a short period of time.
It stores data for temporary use.
Disadvantage:
•
•
Cache memory has limited capacity.
It is very expensive.
MEMORY UNITS OF COMPUTER
Primary Memory (Main Memory)
A memory is just like a human brain. It is used to store data and instruction. Computer memory is the
storage space in computer where data is to be processed and instructions required for processing are
stored.
Primary memory holds only those data and instructions on which computer is currently working. It
has limited capacity and data get lost when power is switched off.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
15
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
It is generally made up of semiconductor device. These memories are not as fast as registers. The
data and instruction required to be processed earlier reside in main memory. It is divided into two
subcategories RAM and ROM.
Because of the extra space in the matrix, SRAM uses more chips than DRAM for the same amount of
storage space, thus making the manufacturing costs higher.
Static RAM is used as cache memory needs to be very fast and small.
Characteristic of Main Memory
Characteristic of the Static RAM
•
•
•
•
•
•
•
These are semiconductor memories.
It known as main memory.
Usually volatile memory.
Data is lost in case power is switch off.
It is working memory of the computer.
Faster than secondary memories.
A computer cannot run without primary memory.
•
•
•
•
•
•
•
It has long data lifetime
There is no need to refresh
Faster
Used as cache memory
Large size
Expensive
High power consumption
Dynamic RAM (DRAM)
DRAM, unlike SRAM, must be continually refreshed in order for it to maintain the data. This is
done by placing the memory on a refresh circuit that rewrites the data several hundred times per
second. DRAM is used for most system memory because it is cheap and small. All DRAMs are made
up of memory cells. These cells are composed of one capacitor and one transistor.
fig : RAM
A RAM constitutes the internal memory of the CPU for storing data, program and program result. It
is read/write memory. It is called random access memory (RAM).
Since access time in RAM is independent of the address to the word that is, each storage location
inside the memory is as easy to reach as other location & takes the same amount of time. We can
reach into the memory at random & extremely fast but can also be quite expensive.
RAM is volatile, i.e. data stored in it is lost when we switch off the computer or if there is a power
failure. Hence a backup uninterruptible power system(UPS) is often used with computers. RAM is
small , both in terms of its physical size and in the amount of data it can hold.
RAM is of two types
•
•
Characteristic of the Dynamic RAM
•
•
•
•
•
•
•
It has short data lifetime
Need to refresh continuously
Slower as compared to SRAM
Used as RAM
lesser in size
Less expensive
Less power consumption
ROM stands for Read Only Memory. The memory from which we can only read but cannot write on
it. This type of memory is non-volatile. The information is stored permanently in such memories
during manufacture.
Static RAM (SRAM)
Dynamic RAM (DRAM)
A ROM, stores such instruction as are required to start computer when electricity is first turned on,
this operation is referred to as bootstrap. ROM chip are not only used in the computer but also in
other electronic items like washing machine and microwave oven.
Static RAM (SRAM)
The word static indicates that the memory retains its contents as long as power remains applied.
However, data is lost when the power gets down due to volatile nature. SRAM chips use a matrix of
6-transistors and no capacitors. Transistors do not require power to prevent leakage, so SRAM need
not have to be refreshed on a regular basis.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
16
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
•
Fig : ROM
Its contents are always known and can be verified
Secondary Memory
Following are the various types of ROM
This type of memory is also known as external memory or non-volatile. It is slower than main
memory. These are used for storing Data/Information permanently.
MROM (Masked ROM)
The very first ROMs were hard-wired devices that contained a pre-programmed set of data or
instructions. These kind of ROMs are known as masked ROMs. It is inexpensive ROM.
CPU directly does not access these memories instead they are accessed via input-output routines.
Contents of secondary memories are first transferred to main memory, and then CPU can access
it.For example: disk, CD-ROM,DVD etc.
PROM (Programmable Read only Memory)
Characteristic of Secondary Memory/ ADVNTAGE
PROM is read-only memory that can be modified only once by a user. The user buys a blank PROM
and enters the desired contents using a PROM programmer.Inside the PROM chip there are small
fuses which are burnt open during programming. It can be programmed only once and is not erasable.
EPROM(Erasable and Programmable Read Only Memory)
The EPROM can be erased by exposing it to ultra-violet light for a duration of upto 40 minutes.
Usually, a EPROM eraser achieves this function. During programming an electrical charge is trapped
in an insulated gate region. The charge is retained for more than ten years because the charge has no
leakage path. For erasing this charge, ultra-violet light is passed through a quartz crystal window(lid).
This exposure to ultra-violet light dissipates the charge. During normal use the quartz lid is sealed
with a sticker.
EEPROM(Electrically Erasable and Programmable Read Only Memory)
The EEPROM is programmed and erased electrically. It can be erased and reprogrammed about ten
thousand times. Both erasing and programming take about 4 to 10 ms (mille second). In EEPROM,
any location can be selectively erased and programmed. EEPROMs can be erased one byte at a time,
rather than erasing the entire chip. Hence, the process of re-programming is flexible but slow.
•
•
•
•
•
•
•
•
These are magnetic and optical memories.
It is known as backup memory.
It is non-volatile memory.
Data is permanently stored even if power is switched off.
It is used for storage of the data in the computer.
Computer may run without secondary memory.
Slower than primary memories.
The storage capacity are expressed in terms of Bytes.
SECONDARY STORAGES:
1) MAGNETIC DISKS.: such as Hard Disk , Floppy Disk,
2) MAGNETIC TAPES.
3) OPTICAL DISKS.: CD, DVD, VCD, Etc
4) FLASH DRIVES.
MAGNETIC DISKS
1) HARD DISK
Advantages of ROM
•
•
•
•
•
•
Non-volatile in nature
These can not be accidentally changed
Cheaper than RAMs
Easy to test
More Reliable than RAMs
These are static and do not require refreshing
Source: Pradeepkumar. K.
FIG : hard disk
WEB SOURCE: www.pradikshana.weebly.com
fig: CD Drive
17
FUNDAMENTALS OF COMPUTER
•
•
•
•
•
•
•
•
•
•
B.Com–II sem.
Magnetic disks are group of round flat metal plates. Which are coated with the magnetic
oxide.
As they are made up of metal/ alluminium its called as HARD DISKS
Magnetic disks provides long term storage.
It is made up of many disk internally alligned and adjusted.
Each disk has both side read / write heads.
Disks are made up of concentric circles
Each circle is divided into tracks and sectors
Each sector is again consists of blocks where data is stored.
The speed is generally measured in RPM(Revolutions Per Minute).
Read / Write heads are responsible for reading or writing data.
TRACK
2) FLOPPY DISK
•
•
•
•
•
•
Floppy disk is thin flexible circular plate coated with magnetic oxide and kept inside a
square plastic jacket.
Floppy disks are made up of Single plastic plate coated with magnetic oxide.
Which in turn has several track,
Tracks are divided into sectors.
Floppy Disk Drives are used for Floppy.
Different types of floppy disks
Size
5.25
3.5
Type
capacity
1) Double sided, double density
2) Double sided, high density
1) Double sided, double density
2) Double sided, high density
360 KB
1.2MB
720 KB
1.44 MB
SECTOR
•
Fig: disk
design
.
OPTICAL DISKS
• TYPES: CD ROM( compact disk Read Only Memory)
o CD RW( compact disk Read / Write)
o DVD RW(Digita Versatile Disk Read / Write)
o BLUE RAY
1) CD ROM( Compact Disk Read Only Memory)
•
•
•
•
•
•
•
These are secondary storage devices.
Once data is recorded it cannot be changed (so called READ ONLY)
It has more memory than floppy.
About 700 MB can be stored on CD.
Now a days even CD Re - Writable also available.
To use CD we need CD Drives.’
Data is stored on this by using LASER.
2) DVD (Digital Versatile Disk)
•
•
•
DVD are high definition optical disks.
These has more capacity than CD
About 4.7 GB data can be stored on to the CD.
3) Blue Ray disks
•
Source: Pradeepkumar. K.
This is an advanced version of optical disk.
WEB SOURCE: www.pradikshana.weebly.com
18
FUNDAMENTALS OF COMPUTER
•
•
•
•
B.Com–II sem.
Few higher storage units are following
Developed by Blue Ray Disk Association.
It uses Blue Violet LASER technology.
It can hold up to 25 GB. Data with single Layer.
It can hold up to 50 GB data with Double Layer.
Sr. No.
1
2
3
4
5
6
7
8
9
FLASH MEMORY
•
•
•
•
•
•
These work on semiconductor technology.
Can be carried easily.
Very small in size.
Which has some limited millions of read or write capacity.
Several GB data can be stored.
Usually comes with USB( Universal Serial Bus).
Unit
0 or 1
4 Bits
2 Nibble or 8 Bits
1024 Bytes
1024 Bytes
1024 KB
1024 MB
1024 GB
1024 TB
Description
1 bit
1 Nibble
1 Byte
1 Kilo Bytes
Kilobyte (KB)
Megabyte (MB)
GigaByte (GB)
TeraByte (TB
PetaByte (PB)
⇒Following are the main memory storage units:
Sr. No.
Unit
1
Bit (Binary Digit)
2
Nibble
3
Byte
4
Word
Description
A binary digit is logical 0 & 1 representing a passive or an active state
of a component in an electric circuit.
A group of 4 bits is called nibble.
A group of 8 bits is called byte. A byte is the smallest unit which can
represent a data item or a character.
A computer word like a byte, is a group of fixed number of bits
processed as a unit which varies from computer but is fixed for each
computer.
The length of a computer word is called word-size or word length and
it may be as small as 8 bits or may be as long as 96 bits.
A computer stores the information in the form of the computer words.
Motherboard
The motherboard serves as a single platform to connect all of the parts of a computer together. A
motherboard connects CPU, memory, hard drives, optical drives, video card, sound card and other
ports and expansion cards directly or via cables. It can be considered as the backbone of a computer.
fig: Motherboard
Features
fig: USB flash drive
•
•
•
•
Motherboard varies greatly in supporting various types of components.
Normally a motherboard supports a single type of CPU and few types of memories.
Video Cards, Hard disks, Sound Cards have to compatible with motherboard to function
properly.
Motherboards, cases and power supplies must be compatible to work properly together.
Popular Manufacturers
•
•
Source: Pradeepkumar. K.
Intel
ASUS
WEB SOURCE: www.pradikshana.weebly.com
19
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
COMPUTER MEMORY
PRIMARY (MAIN)
MEMORY
RAM
CACHE
MEMORY
ROM
SRAM
EROM
DRAM
EEPROM
PROCESSOR
REGISTERS
MAGNETIC DISK/TAPE
SECONDARY
MEMORY
FLASH MEMORY
FLOPPY DISK
ZIP DRIVE/ DISK
OPTICAL DISK
PEN DRICVE
CD-ROM
CD-RW
MEMORY CARDS
HARD DISK
DVD ROM
DVD RW
BLUE RAY DISK
PDA
MMC
SD
OCR
OMR
MICR
VDU
ABBREVATIONS
Personel Digital Assistant
MultiMedia Card
Secure Digital Card
Optical CharacterReader
Optical Mark Reader
Magnetic Ink Character Reader
Visual Display Unit
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
20
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
The following table highlights the major difference between the RAM memory and ROM memory
Options
Elaboration
Accessibility
RAM
ROM
Random Access Memory
Read Only memory
NzÀÄ/§gÀºÀ ¸ÀAUÀæºÀuÉAiÀiÁVzÉ
NzÀÄ ªÀiÁvÀæ ¸ÀAUÀæºÀuÉAiÀiÁVzÉ
The processor cannot directly access the information
In reference with the processor, the information stored in that is stored in the ROM. In order to access the ROM
information, first the information will be transferred
the RAM is easily accessed
into the RAM and then it gets executed by the
processor
£ÉÃgÀªÁV ºÁUÀÆ ¸ÀÄ®¨sÀªÁV ªÀiÁ»wAiÀÄ£ÀÄß ¸ÀAUÀ滸ÀlÄÖPÉƼÀÄîvÀÛªÉ
sEzÀÄ £ÉÃgÀªÁV ªÀiÁ»wAiÀÄ£ÀÄß ¸ÀAUÀæºÀ¹lÄÖPÉƼÀÄîªÀÅ¢®è. ªÉÆzÀ®Ä
ªÀiÁ»wAiÀÄ£ÀÄß gÁåªÀiï UÉ ªÀUÁ𻹠£ÀAvÀgÀ QæAiÉÄUÉƼÀ¥ÀlÖ
ªÀiÁ»wAiÀÄ£ÀÄß ¸ÀAUÀ滸À¯ÁUÀĪÀÅzÀÄ.
Working type (PÁAiÀÄðzÀ
§UÉ)
Storage(¸¸ÀAUÀæºÀuÉ)
Speed(ªÉÃUÀ)
The ROM memory only allows the user to read the
Both the read and write operations can be performed
information. User cannot make any changes to the
over the information that is stored in the RAM
information.
NzÀÄ ªÀÄvÀÄÛ §gÀºÀ ¸ÀägÀuÉAiÀiÁVzÉ. QæAiÉÄAiÀÄ°ègÀĪÀ ªÀiÁ»wAiÀÄ£ÀÄß
NzÀÄ ªÀiÁvÀæ ¸ÀägÀuÉAiÀiÁVzÉ, §¼ÀPÉzÁgÀ£ÀÄ AiÀiÁªÀÅzÉ jÃw §zÀ¯ÁªÀuÉ
¸ÀAUÀ滸ÀĪÀÅzÀÄ.
ªÀiÁqÀ®Ä ¸ÁzsÀå«®è.
RAM memory is only used to store the temporary
ROM memory is used to store permanent information
information.
and cannot be deleted.
EzÀÄ vÁvÁÌ°PÀ ¸ÀägÀuÉAiÀiÁVzÉ
EzÀÄ ¢ÃWÀðPÁ°PÀ ¸ÀägÀuÉAiÀiÁVzÉ. ªÀÄvÉÛ C½¸À®Ä ¸ÁzsÀå«®è.
the accessing speed of RAM is faster, it assist the
processor to boost up the speed
QæAiÀiÁ ªÉÃUÀ ºÉZÀÄÑ
Structure(gÀZÀ£É)
Speed is slower in comparison with RAM, ROM
cannot boost up the processor speed
QæAiÀiÁ ªÉÃUÀ PÀrªÉÄ
The RAM is an chip, which is in the rectangle form and ROMs are generally the optical drivers, which are
is inserted over the mother board of the computer
made of magnetic tapes.
gÁåªÀiï DAiÀiÁvÁPÁgÀzÀ ©¯ÉèAiÀiÁPÁgÀzÀ°è EzÀÄÝ, EzÀ£ÀÄß UÀtPÀAiÀÄAvÀæzÀ
gÉÆêÀiï MAzÀÄ D¦ÖPÀ¯ï r¸ïÌ DVzÀÄÝ, PÁAwÃAiÀÄ ¸ÀÄgÀĽUÀ½AzÀ
ªÀÄzÀgï ¨ÉÆÃqÀð£À°è ¸ÉÃj¸À¯ÁVgÀÄvÀÛzÉ.
ªÀiÁqÀ®ànÖgÀÄvÀÛzÉ.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
21
FUNDAMENTALS OF COMPUTER
Cost(¨É¯É)
B.Com–II sem.
The price of RAMs are comparatively high
The price of ROMs are comparatively low
zÀĨÁj ¨É¯É
PÀrªÉÄ ¨É¯É
Chip size(UÁvÀæ)
Types(¥ÀæPÁgÀUÀ¼ÀÄ)
Physically size of ROM chip is smaller than RAM
Physically size of RAM chip is larger than ROM chip
chip.
gÁåªÀiï gÉÆêÀiïVAvÀ UÁvÀæzÀ°è zÉÆqÀØzÁVgÀÄvÀÛzÉ.
gÉÆêÀiï gÁåªÀiï VAvÀ UÁvÀæzÀ°è aPÀÌzÁVgÀÄvÀÛzÉ
The RAM memory is categorized into two types they are The ROM memory is categorized into three types,
the:
they are:
gÁåªÀiï£À JgÀqÀÄ ¥ÀæPÁgÀUÀ¼ÀÄ
gÉÆêÀiï£À ¥ÀæPÁgÀUÀ¼ÀÄ F PɼÀV£ÀAwªÉ.
Statistic RAM (SRAM) and Dynamic RAM (DRAM)
PROM (Programmable Read Only memory), EPROM
(Erasable Programmable Read Only memory) and
EEPROM (Electrically Erasable Programmable Read
Only memory)
The following table list out some of the key differences between the primary and secondary memory:
Primary memory(¥ÁæxÀ«ÄPÀ ¸ÀägÀuÉ)
Secondary memory(¢éwÃAiÀÄ ¸ÀägÀuÉ)
The memory devices used for primary memory are semiconductor The secondary memory devices are magnetic and optical
memories
memories.
EªÀÅ ¸É«ÄPÀAqÀPÀÖgï ¸ÀägÀuÉUÀ¼ÁVªÉ.
EªÀÅ PÁAwÃAiÀÄ ºÁUÀÆ D¦ÖPÀ¯ï ¸ÀägÀuÉUÀ¼ÁVªÉ.
The primary memory is categorized as volatile and non volatile The secondary memory is always non volatile
memories, RAM is the volatile memory and ROM is the non volatile EªÀÅ ¢ÃWÀðPÁ°PÀ ¸ÀägÀuÉUÀ¼ÁVªÉ.
memory
EªÀÅUÀ¼À°è C®àPÁ°PÀ ºÁUÀÆ ¢ÃWÀðPÁ°PÀ JA§ ¸ÀägÀuÉUÀ¼À£ÀÄß PÁt§ºÀÄzÀÄ . gÁåªÀiï
C®¥ÀPÁ°PÀ ºÁUÀÆ gÉÆêÀiï ¢ÃWÀðPÁ°PÀ.
The primary memory is composed of programs and data that are The secondary memory is enough capable to store huge amount
presently being used by the micro processor
of information
¸ÀÆPÀëöä ¸ÀA¸ÀÌgÀuÉAiÀÄ°è£À zÀvÁÛA±ÀUÀ¼À£ÀÄß £ÉgÀªÁV ºÁUÀÆ C®àPÁ°PÀªÁV ±ÉÃRj¹qÀÄvÀÛzÉ.
EªÀÅUÀ¼ÀÄ ¸ÁPÁUÀĪÀµÀÄÖ ªÀiÁ»wAiÀÄ£ÀÄß ¢ÃWÀðPÁ°PÀªÁV ±ÉÃRj¹qÀÄvÀÛªÉ.
The primary memories are more effective and fast to interact with the
The secondary memories are somewhat slow in interacting with
micro processor
the micro processor, when compared with the primary memory.
EªÀÅUÀ¼À ¥ÀjuÁªÀÄPÁjAiÀiÁV ºÁUÀÆ ªÉÃUÀªÁV ¸ÀÆPÀëöä ¸ÀA¸ÀÌgÀt ©¯ÉèAiÉÆA¢UÉ ¥ÀæwQæ¬Ä¸ÀÄvÀÛªÉ. EªÀÅUÀ¼ÀÄ ¥ÁæxÀ«ÄPÀ ¸ÀägÀuÉVAvÀ ¤zsÁ£ÀªÁV ¥ÀæwQæ¬Ä¸ÀÄvÀÛªÉ.
Primary memory is known as main memory
Source: Pradeepkumar. K.
Secondary memory is known as additional memory or back
WEB SOURCE: www.pradikshana.weebly.com
22
FUNDAMENTALS OF COMPUTER
EªÀÅUÀ¼À£ÀÄß ªÀÄÄRå/¥ÀæzsÁ£À ¸ÀägÀuÉ JAvÀ®Æ PÀgÉAiÀÄĪÀgÀÄ.
B.Com–II sem.
memory
EªÀÅUÀ¼À£ÀÄß ºÉZÀÄѪÀj ¸ÀägÀuÉ JAvÀ®Æ PÀgÉAiÀÄĪÀgÀÄ.
These memories are also called as internal memory
These memories are also called as external memory
DAvÀjPÀ ¸ÀägÀuÉ JAvÀ®Æ PÀgÉAiÀÄĪÀgÀÄ.
¨ÁºÀå ¸ÀägÀuÉ JAvÀ®Æ PÀgÉAiÀÄĪÀgÀÄ.
Primary memory is temporary
The secondary memory is permanent
vÁvÁÌ°PÀ ¸ÀägÀuÉUÀ¼ÀÄ PÀÆqÁ DVªÉ.
¢ÃWÀðPÁ°PÀ ¸ÀägÀuÉUÀ¼ÁVªÉ.
Commonly used primary memory (main memory) available in the range Generally secondary memories range between(¸ÀägÀuÉAiÀÄ ¸ÁªÀÄxÀåð)
of (¸ÀägÀuÉAiÀÄ ¸ÁªÀÄxÀåð) 512 MB to 8 GB RAMs.
80 GB to 4 TB Hard Disc Drives.
The secondary memory devices are connected to the computer
The primary memory devices are connected to the computer through through Cables
“slots”
EªÀÅUÀ¼À£ÀÄß UÀtPÀAiÀÄAvÀæzÀ PÉÃA¢æÃAiÀÄ ¸ÀA¸ÀÌgÀt WÀlPÀ ºÁUÀÆ AiÀÄÄ J¸ï © ¥ÉÆÃmïð
PÉÃA¢æÃAiÀÄ ¸À¸ÀÌgÀt WÀlPÀzÀ ªÀÄzÀgï ¨ÉÆÃqÀð£À°ègÀĪÀ ¸Áèmï UÀ¼À°è eÉÆÃr¸À¯ÁVgÀÄvÀÛzÉ.
ºÁUÀÆ qÉæöʪïUÀ¼À°è eÉÆÃr¸À§ºÀÄzÀÄ.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
23
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Application Software
Software
(s/w)
Application software are the software that are designed to satisfy a particular need of a particular
environment. All software prepared by us in the computer lab can come under the category of
Application software.
⇒ defn:” set of programs “, which is designed to perform a well defined function. A program is a
sequence of instructions written to solve a particular problem.
TYPES OF SOFTWARE
•
•
•
Application software may consists of a single program, such as a Microsoft's notepad for writing
and editing simple text. It may also consists of a collection of programs, often called a software
package, which work together to accomplish a task, such as a spreadsheet package.
Examples of Application software are following
System Software
Application Software
Development s/w
System Software
The system software is collection of programs designed to operate, control and extend the
processing capabilities of the computer itself. System software are generally prepared by computer
manufactures.
These softwares comprise of programs written in low level languages which interact with the
hardware at a very basic level. System software serves as the interface between hardware and the
end users.
•
•
•
•
•
•
•
•
•
Payroll Software
Student Record Software
Inventory Management Software
Income Tax Software
Railways Reservation Software
Microsoft Office Suite Software
Microsoft Word
Microsoft Excel
Microsoft Powerpoint
Some examples of system software are Operating System, Compilers, Interpreter, Assemblers etc.
Features of Application Software are following
Features of System Software are following
•
•
•
•
•
•
•
•
Close to system.
Fast in speed.
Difficult to design.
Difficult to understand.
Less interactive.
Smaller in size.
Difficult to manipulate.
Generally written in low level language.
Source: Pradeepkumar. K.
•
•
•
•
•
•
•
•
It is close to user.
It is easy to design.
More interactive.
Slow in speed.
Generally written in high level language.
Easy to understand.
Easy to manipulate and use.
Bigger in size and requires large storage space.
*Development s/w: used for developing new softwares
Such as: C,C++, java etc
WEB SOURCE: www.pradikshana.weebly.com
24
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
•
” OPERATING SYSTEM “
•
•
•
Defn: “An operating system is a program that acts as an interface between the
software and the computer hardware”.
It is an integration set of specialised programs that are used to manage overall resources
and operations of the computer.
It is specialised software that controls and monitors the execution of all other programs
that reside in the computer, including application programs and other system software.
Objectives of Operating System
•
•
•
•
•
•
•
•
•
•
•
•
Making a computer system convenient to use in an efficient manner
To hide the details of the hardware resources from the users
To provide users a convenient interface to use the computer system.
To act as an intermediary between the hardware and its users and making it easier for the
users to access and use other resources.
Manage the resources of a computer system.
keep track of who is using which resource, granting resource requests, according for
resource using and mediating conflicting requests from different programs and users.
The efficient and fair sharing of resources among users and programs
•
File Management -- Allocates the resources. De-allocates the resource. Decides who
gets the resources.
Security -- By means of passwords & similar other techniques, preventing unauthorized
access to programs & data.
Job accounting -- Keeping track of time & resources used by various jobs and/or users.
Control over system performance -- Recording delays between request for a service &
from the system.
Interaction with the operators -- The interaction may take place via the console of the
computer in the form of instructions. Operating System acknowledges the same, do the
corresponding action and inform the operation by a display screen.
Error-detecting aids -- Production of dumps, traces, error messages and other
debugging and error-detecting methods.
Coordination between other software and users -- Coordination and assignment of
compilers, interpreters, assemblers and other software to the various users of the
computer systems.
Types of O.S.
1: TIMESHARING OS: it allocates resources on time dependent fashion, to serve programs
simultaneously. Each user gets CPU for some short period of time. But user feels that he alone is
using the CPU.
2: ON-LINE OS: the remote terminals and servers working on-line. As Banks , reservations etc
3: REAL TIME OS: controls the operations of a physical systems such as satellite in orbit may be
controlled..
4: BATCH PROCESSING OS: this kind os uses automated job to job transiton. Each user has to
create his own program and gives to computer, here operator collects similar type jobs and makes
BATCH.
O.S. Interaction:
5: JOB CONTROL LANGUAGE: it uses Job Control Language to separate jobs and execute.
Characteristics/ Functions of Operating System
•
•
•
FILE: IS COLLECTION OF RELATED DATA & INFORMATION.
Memory Management -- It keeps tracks of primary memory i.e what part of it are in use
by whom, what part are not in use etc.Allocates the memory when the process or program
request it.
Processor Management -- Allocate the processor(CPU) to a process. Deallocate
processor when processor is no longer required.
Device Management -- Keep tracks of all devices.This is also called I/O controller.
Decides which process gets the device when and for how much time.
Source: Pradeepkumar. K.
FOLDER / DIRECTORY: IS COLLECTION OF FILES.
WEB SOURCE: www.pradikshana.weebly.com
25
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
The following table list out some of the key differences between the Application software
and System software:
Subject
(«µÀAiÀÄ)
Definition
(ªÁåSÉå)
Application Software
C£Àé¬ÄPÀ vÀAvÁæA±À
Application software is computer
software designed to help the user to
perform specific tasks.
§¼ÀPÉzÁgÀ£À CªÀ±ÀåPÀvÉUÉ vÀPÀÌAvÉ gÀa¸À¯ÁzÀ
vÀAvÁæA±ÀUÀ¼ÁVªÉ.
System software is computer software designed to operate the computer
hardware and to provide a platform for running application software.
UÀtPÀAiÀÄAvÀæzÀ°è AiÀÄAvÁæA±ÀUÀ¼À PÁAiÀÄðªÉÊRjUÉ ¸ÀA§A¢üvÀ ¤ªÀðºÀuÉUÁV ªÉÆzÀ¯Éà gÀa¸À¯ÁzÀ
vÀAvÁæA±ÀUÀ¼ÁVªÉ.
Purpose
(§¼ÀPÉ)
It is specific purpose software.
¤¢ðµÀÖ §¼ÀPÉAiÀÄ vÀAvÁæA±ÀUÀ¼ÁVªÉ.
It is general-purpose software.
¸ÁªÀiÁ£Àå §¼ÀPÉAiÀÄ vÀAvÁæA±ÀUÀ¼ÁVªÉ.
Classificati
Package Program,
on
(ªÀVðPÀgÀt)
Customized Program
System Software
ªÀåªÀ¸ÁÜ¥À£Á vÀAvÁæA±À
Time Sharing,
Resource Sharing,
Client Server
Batch Processing Operating System
Real time Operating System
Multi-processing Operating System
Multi-programming Operating System
Distributed Operating System
Environme
Application Software performs in a
System Software Create his own environment to run itself and run other
nt
(gÀZÀ£É)
environment which created by
application.
EzÀÄ vÀ£ÀßzÉà DzÀ gÀZÀ£ÉAiÀÄ£ÀÄß ºÉÆA¢zÀÄ, vÁ£Éà QæAiÉÄUÉƼÀ¥ÀqÀĪÀÅzÀgÀ eÉÆvÉUÉ ¨ÉgÉ QæAiÉÄUÀ¼À£ÀÄß
System/Operating System
C£Àé»PÀ vÀAvÁæA±ÀªÀÅ QæAiÉÆÃvÉÛÃfPÀ ªÀåªÀ¸ÉÜAiÀÄ gÀZÀ£É
QæAiÉÄUÉƼÀ¥Àr¸ÀÄvÀÛzÉ.
ªÀÄÆSÁAvÀgÀ QæAiÉÄUÉƼÀ¥ÀqÀĪÀ vÀAvÁæA±ÀªÁVzÉ.
Execution
Time
(PÁAiÀÄð
It executes as and when required.
CªÀ±Àå«zÁÝUÀ QæAiÉÄUÉƼÀ¥Àr¸À§ºÀÄzÀÄ.
It executes all the time in computer.
EzÀÄ ¸ÀvÀvÀªÁV QæAiÉÄUÉƼÀ¥ÀqÀĪÀÅzÀÄ.
¸ÀªÀÄAiÀÄ)
Essentiality
(CªÀ±ÀåPÀvÉ)
Number
(¸ÀASÉåUÀ¼ÀÄ)
Application is not essential for a
computer.
UÀtPÀAiÀÄAvÀæPÉÌ F vÀAvÁæA±ÀzÀ CªÀ±ÀåPÀvɬĮè.
The number of application software is
much more than system software.
C£ÉÃPÀ C£Àé»PÀ vÀAvÁæA±ÀUÀ¼ÀÄ ªÀåªÀ¸ÁÜ¥À£À
vÀAvÁæA±ÀzÀ ¨sÁUÀUÀ¼ÁVªÉ.
Source: Pradeepkumar. K.
System software is essential for a computer UÀtPÀAiÀÄAvÀæPÉÌ F vÀAvÁæA±ÀzÀ CªÀ±ÀåPÀvɬÄzÉ.
The number of system software is less than application software.
DzÀgÉ C£Àé»PÀ vÀAvÁæA±ÀUÀ¼À°è ªÀåªÀ¸ÁÜ¥À£À vÀAvÁæA±ÀUÀ¼ÁVgÀĪÀÅ¢®è..
WEB SOURCE: www.pradikshana.weebly.com
26
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Symbols are very few
Advantage:
Easy to understand
Easy to learn
Easy to locate errors
Modification is possible
“COMPUTER LANGUAGE”
The language used to communicate with the computers is Binary language.
These are made up of 0’s and 1’s.
2) HIGH LEVEL LANGUAGE:
HLL is a language which uses English like statements for coding. A familiar statements
and words are used for programming.
Eg: C, C++, JAVA, COBOL, VB, .NET, BASIC, FORTRAN ETC.
Basically there are two types:
1. LOW LEVEL LANGUAGE(LLL)
2. HIGH LEVEL LANGUAGE(HLL)
1)LOW LEVEL LANGUAGE:
LLL is machine oriented language and machine dependent language, where each instruction is a
machine code. Its highly known only to machines,
There are 2 types:
1: machine language
2: assembly language.
i)
Machine language:
Language completely written in binary codes( 0 and 1).
Used in 1st gen computers.
It has two parts a) command b) operand
Limitations:
Machine dependent: cannot be used with different designed machine
Difficult to program
Difficult to manage
Experts are required
Error prone
Difficult to modify
Difficult to detect the errors
Advantage
High speed
No translator required
ii) Assembly language
Language which uses the mnemonic or symbolic instructions.
Known as symbolic programming language.
Translators are used to translate the symbols into binary language.
Limitations:
Machine dependent
Takes more execution time as translation process has to done
Knowledge of hardware is needed
Source: Pradeepkumar. K.
Advantage:
Easier to learn
Easier to code
Requires less coding time
Easy to modify, debug
Complexity is reduced
Limitations;
Extra time is taken by converters for translation
Requires a translator software.
TRANSLATORS
•
•
These are s/w used to translate programs written in high level languages to machine level
languages.
Types:
INTERPRETERS
COMPILERS
ASSEMBLERS
INTERPRETER
•
•
•
•
It’s a kind of translator which translates high level language into machine level
language.
It takes a single line at a time.& converts to machine code.
If any error occurs , it stops next line conversion.
Ex: BASIC interpreters, JAVA interpreters
COMPILERS
•
It’s a kind of translator which converts high level language to
machine language.
• It takes complete set of statements to convert at a time.
• If any error occurs, then all errors are listed at once for correcting.
• Ex: c compiler, COBOL compiler etc.
WEB SOURCE: www.pradikshana.weebly.com
27
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Difference between INTERPRETER & COMPILER
•
•
•
•
•
INTERPRETER
Translates one line at a time
Need less memory
Errors are listed suddenly
Execution is slower
Source and machine code both
required for execution
•
•
•
•
•
COMPILER
Translates whole set a time
Need more memory
Errors are listed at once
Execution is fast
Only machine code is required
ASSEMBLER
•
•
It converts assembly language program to machine language
Ex: AUTOCODER, PLAN etc
Difference between High Level Language (HLL) and Low Level Language (LLL)
Subject
High-level Language
Low-level languages
1. Learning
High-level languages are easy to learn. Low-level languages are difficult to
§¼ÀPÉ/PÀ°PÉ
G£ÀßvÀ ªÀÄlÖzÀ ¨sÁµÉ §¼ÀPÉ Cwà ¸ÀÄ®¨sÀ
learn.
PɼÀªÀÄlÖzÀ ¨sÁµÉ §¼ÀPÉ QèµÀÖPÀgÀ
2 Understanding
High level languages are near to
Low-level languages are far from
CxÀðªÁUÀÄ«PÉ
human languages
human languages.
EzÀÄ §¼ÀPÉzÁgÀ¤UÉ ºÀwÛgÀzÀ ¨sÁµÉAiÀiÁVzÉ.
EzÀÄ §¼ÀPÉzÁgÀ¤UÉ CxÀðªÁUÀzÀ ºÁUÀÆ
£É£À¦lÄÖPÉƼÀî¨ÉÃPÁzÀ ¨sÁµÉAiÀiÁVzÉÉ.
3. Execution
Programs in high-level languages are
Programs in low-level languages are
QæAiÉÄ
slow in execution.
fast in execution.
QæAiÀiÁªÉÃUÀ ¤zsÁ£À
ºÉaÑ£À QæAiÀiÁªÉÃUÀ
4. Modification
Programs in high-level languages are
Programs in low-level languages are
§zÀ¯ÁªÀuÉ
easy to modify.
difficult to modify
EªÀÅUÀ¼À£ÀÄß §zÀ¯Á¬Ä¸ÀĪÀÅzÀÄ ¸ÀÄ®¨sÀ
F ¨sÁµÉAiÀÄ£ÀÄß §zÀ¯Á¬Ä¸ÀĪÀÅzÀÄ PÀµÀÖPÀgÀ
5. Language
User Language (just like English)
Binary System ‘0 & 1’
¨sÁµÉ
§¼ÀPÉzÁgÀ¤UÉ ºÀwÛgÀªÁzÀ ¨sÁµÉUÀ¼ÀÄ. GzÁºÀgÀuÉ
¢éªÀiÁ£À ¥ÀzÀÞw ‘0 & 1’
EAVèõï
6. Uses
§¼ÀPÉ
7. Language
Translator
¨sÁµÁAvÀgÀPÀ vÀAvÁæA±À
These languages are normally used to
write application programs
F ¨sÁµÉUÀ¼À£ÀÄß ¸ÁªÀiÁ£ÀåªÁV C£Àé»PÀ
PÁAiÀiÁðPÀæªÀÄUÀ¼À£ÀÄß §gÉAiÀÄ®Ä §¼À¸ÀĪÀgÀÄ.
Compiler and Interpretor Software
«ªÀgÀtPÀvÀð & PÉÆæÃrPÁgÀPÀ vÀAvÁæA±À
Source: Pradeepkumar. K.
ENIAC
EDSAC
UNIVAC
FORTRAN
COBOL
BASIC
MIPS, KIPS, BIPS
USB
CPU
PC
ALU
CU
BCD
EBCDIC
ISCII
ASCII
RAM
ROM
EEPROM
KB, MB, GB, TB
DOS
FAT
NTFS
RPM, CPM, LPM
CD
DVD
CRT
LCD
TFT
LED
ABBREVATIONS
Electronic Numeric Integrator & calculator
Electronic Delay Storage Automatic Computer
UNIV Automatic Computer
FORmula TRANslation
Common Business Oriented Language
Beginners All Purpose Symbolic Instruction Code
Million Instruction Per Second( K: Kile, B:Billion)
Universal Serial Bus
Central Processing Unit
Personal Computer
Arithmetic Logic Unit
Control Unit
Binary Coded Decimal
Extended BCD Interchange Code
Indian Standard Code for Information Interchange
American Standard Code for Information Interchange
Random Access Memory
Read Only Memory
Electronically Erasable Programmable ROM
Kilo Byte (M:Mega, G:Giga, T:Terra)
Disk Operating System
File Allocation Table
New Technology File System
Revolution Per Minute (C: character, L:Line)
Compact Disk
Digital Versatile Disk
Cathode Ray Tube
Liquid Crystal Display
Thin Film Transistor
Light Emitting Diode
These languages are normally used to
write hardware programs.
F ¨sÁµÉUÀ¼À£ÀÄß ¸ÁªÀiÁ£ÀåªÁV AiÀÄAvÁæA±À
PÁAiÀiÁðPÀæªÀÄUÀ¼À£ÀÄß §gÉAiÀÄ®Ä §¼À¸ÀĪÀgÀÄ.
Assembler Software
eÉÆÃqÀuÁPÁgÀPÀ vÀAvÁæA±À
WEB SOURCE: www.pradikshana.weebly.com
28
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
As a computer programmer or an IT professional, you should understand the following number
systems which are frequently used in computers.
⇒ NUMBER SYSTEM
Binary Number System
The number system is writing andmathematical notation system, for expressing and
representing numbers of a given set using dedicated symbols consistently.
Types:
Number system
1
2
3
4
S.N
.
Binary number system
Decimal number system
Octal number system
Hexadecimal system
Binary Number System
Base 2. Digits used: 0, 1
2
Octal Number System
Base 8. Digits used: 0 to 7
4
•
•
•
•
Base
number
2
10
8
16
Uses two digits, 0 and 1.
Also called base 2 number system
Each position in a binary number represents a 0 power of the base (2). Example 20
Last position in a binary number represents a x power of the base (2). Example 2x where x
represents the last position - 1.
Example
Binary Number: 101012
Number System & Description
1
Characteristics
Calculating Decimal Equivalent:
Step
Binary Number
Step
101012
1
Step
101012
2
Hexa Decimal Number System
Base 16. Digits used: 0 to 9, Letters used: A- F
Step
101012
3
Decimal Number
4
3
((1 x 2 ) + (0 x 2 ) + (1 x 22) + (0 x 21) + (1 x 20))10
(16 + 0 + 4 + 0 + 1)10
2110
Decimal Number System
The number system that we use in our day-to-day life is the decimal number system. Decimal number
system has base 10 as it uses 10 digits from 0 to 9. In decimal number system, the successive
positions to the left of the decimal point represent units, tens, hundreds, thousands and so on.
Each position represents a specific power of the base (10). For example, the decimal number 1234
consists of the digit 4 in the units position, 3 in the tens position, 2 in the hundreds position, and 1 in
the thousands position, and its value can be written as
(1x103)+ (2x102)+ (3x101)+ (4xl00). (5x10-1 )
1000 + 200 + 30 + 1 . 5x0.1
Note: 101012 is normally written as 10101.
Octal Number System
Characteristics
•
•
•
•
Uses eight digits, 0,1,2,3,4,5,6,7.
Also called base 8 number system
Each position in a octal number represents a 0 power of the base (8). Example 80
Last position in a octal number represents a x power of the base (8). Example 8x where x
represents the last position - 1.
(1234.5 )10
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
29
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Example
Step
19FDE16
4
10646210
Octal Number: 125708
Calculating Decimal Equivalent:
Step
Octal Number
Step
125708
1
Step
125708
2
Decimal to Other Base System
Decimal Number
4
3
2
1
0
((1 x 8 ) + (2 x 8 ) + (5 x 8 ) + (7 x 8 ) + (0 x 8 ))10
Steps
(4096 + 1024 + 320 + 56 + 0)10
Step
125708
3
•
•
549610
•
•
Note: 125708 is normally written as 12570.
Step 1 - Divide the decimal number to be converted by the value of the new base.
Step 2 - Get the remainder from Step 1 as the rightmost digit (least significant digit) of new
base number.
Step 3 - Divide the quotient of the previous divide by the new base.
Step 4 - Record the remainder from Step 3 as the next digit (to the left) of the new base
number.
Hexadecimal Number System
Repeat Steps 3 and 4, getting remainders from right to left, until the quotient becomes zero in Step 3.
Characteristics
The last remainder thus obtained will be the most significant digit (MSD) of the new base number.
•
•
•
•
•
Uses 10 digits and 6 letters, 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F.
Letters represents numbers starting from 10. A = 10. B = 11, C = 12, D = 13, E = 14, F =
15.
Also called base 16 number system
Each position in a hexadecimal number represents a 0 power of the base (16). Example 160
Last position in a hexadecimal number represents a x power of the base (16). Example 16x
where x represents the last position - 1.
Decimal Number: 2910
Calculating Binary Equivalent:
Step Operation Result Remainder
Step 1 29 / 2
14
1
Example
Step 2
Step 3
Step 4
Step 5
Hexadecimal Number: 19FDE16
Calculating Decimal Equivalent:
Step Binary Number
Step
19FDE16
1
Step
19FDE16
2
Step
19FDE16
3
Example
Decimal Number
((1 x 164) + (9 x 163) + (F x 162) + (D x 161) + (E x 160))10
14 / 2
7/2
3/2
1/2
7
3
1
0
0
1
1
1
As mentioned in Steps 2 and 4, the remainders have to be arranged in the reverse order so that the
first remainder becomes the least significant digit (LSD) and the last remainder becomes the most
significant digit (MSD).
((1 x 164) + (9 x 163) + (15 x 162) + (13 x 161) + (14 x 160))10
Decimal Number: 2910 = Binary Number: 111012.
(65536+ 36864 + 3840 + 208 + 14)10
Source: Pradeepkumar. K.
Other base system to Decimal System
WEB SOURCE: www.pradikshana.weebly.com
30
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Octal Number: 258 = Decimal Number: 2110
Steps
•
•
•
Step 1 - Determine the column (positional) value of each digit (this depends on the position
of the digit and the base of the number system).
Step 2 - Multiply the obtained column values (in Step 1) by the digits in the corresponding
columns.
Step 3 - Sum the products calculated in Step 2. The total is the equivalent value in decimal.
Example
Step 2: Convert Decimal to Binary
Step
Step 1
Step 2
Step 3
Step 4
Step 5
Operation
21 / 2
10 / 2
5/2
2/2
1/2
Result
10
5
2
1
0
Remainder
1
0
1
0
1
Binary Number: 111012
Decimal Number: 2110 = Binary Number: 101012
Calculating Decimal Equivalent:
Octal Number: 258 = Binary Number: 101012
Step
Step 1
Step 2
Step 3
Binary Number
Decimal Number
4
((1 x 2 ) + (1 x 23) + (1 x 22) + (0 x 21) + (1 x 20))10
111012
111012
(16 + 8 + 4 + 0 + 1)10
2910
111012
Binary Number: 111012 = Decimal Number: 2910
Other Base System to Non-Decimal System
Steps
•
•
Step 1 - Convert the original number to a decimal number (base 10).
Step 2 - Convert the decimal number so obtained to the new base number.
Example
Calculating Binary Equivalent:
Step 1: Convert to Decimal
Octal Number
278
278
278
BINARY CODING:
BCD( BINARY CODED DECIMAL)
•
•
•
•
•
It is one of oldest system to represent digits
Each digit is translated to binary
It uses 4 bits for coding.
Ex: (234)10 = (0010 0011 0100) bcd
Here 2 = 0010, 3=0011, 4=0100
ASCII CODES
Octal Number: 258
Step
Step 1
Step 2
Step 3
Binary Number: 101012 = Octal Number: 258
Decimal Number
((2 x 81) + (5 x 80))10
(16 + 5 )10
2110
Source: Pradeepkumar. K.
•
•
•
USA based system AMERICAN STANDARD CODE FOR INFORMATION INTERCHANGE.
Almost all manufacture support it.
ASCII has 128 codes. & needs only 7 bits.
ISCII CODES:
•
•
•
It is INDIAN STANDARD CODE FOR INFORMATION INTERCHANGE.
It is 8 bit system
Allows English and Indian scripts.
WEB SOURCE: www.pradikshana.weebly.com
31
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
EBCDIC:
•
•
•
(UNIT II)
BCD is mere 6 bit system that can represent only 64 characters.
Which is not sufficient for supporting all symbols.
So 2 extra bits are added so EXTENDED B.C.D. INTERCHANGE CODE.
WORKING WITH WINDOWS XP
⇒ WHAT IS DATA?
Data can be defined as a representation of facts, concepts or instruction in a formalized manner which
should be suitable for communication , interpretation or processing by human or electronic
machine.Data is represented with the help of characters like alphabets (A-Z,a-z), digits (0-9) or
special characters(+,-,/,*,<,>,= etc).
What is Information?
Information is processed or organized or classified data so that it has some meaningful values to the
receiver.
Data Processing Cycle
•
•
•
•
•
•
WINDOWS XP is OS developed by Microsoft
XP is short form of eXPerience.
WinXP was launched on 25th oct 2001.
Is has service pack 1, 2 and 3.
It has improved User interface with ..
1) multimedia support 2) music tasks 3) file handling, 4) best security
options available, 5) Remote access, 6) remote assistance 7) multi
programming 8) multi tasking, 9) wireless connectivity,10) net connectivity,
11) power management tools, etc.
SHUT DOWN / TURN OFF SYSTEM
This will closes all opened programs and closes the system.
Step to shut down/ turn off system:
Data processing is the re-structuring or re-ordering of data by people or machine to increase their
usefulness & add values for particular purpose.Data processing consists of basic steps input,
processing and output. These three steps constitute the data processing cycle.
1)
2)
3)
Click on START button
Click on SHUT DOWN button
Again click on TURN OFF icon
LOG ON & LOG OFF WINDOWS
•
•
•
Input - In this step the input data are prepared in some convenient form for processing. The
form will depend on the processing machine. For example, when electronic computers are
used, the input data could be recorded on any one of several types of input medium, such as
magnetic disks, tapes and so on.
Processing - In this step input data are changed to produce data in a more useful form. For
example, pay-checks may be calculated from the time cards, or a summary of sales for the
month may be calculated from the sales orders.
Output -Here the result of the proceeding processing step are collected. The particular
form of the output data depends on the use of the data. For example, output data may be
pay-checks for employees.
Source: Pradeepkumar. K.
When a user enter windows environment he is said to be logged in.
Step to log off system
1) Click on START button
2) Click on LOG OFF button
Note: log off closes current user working,
Turn off closes all user working and closes computer completely
WEB SOURCE: www.pradikshana.weebly.com
32
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
•
DEFAULT
ICONS
1) MY
NETWORK
PLACES
ON DESKTOP:
2)MY
COMPUTER
3)INTERNET
EXPLORER
COMMON TASK: it lists some commonly used tasks such as : system tasks, other places,
details etc.
Control menu
4)RECYCLE
BIN
title bar
Menu Bar
5)MY
DOCUMENT
control box
Std tool bar
MY DOCUMENTS: it has folders MY MUSIC, MY VIDEOS, MY PICTURES.
MY NETWORK PLACES
•
•
It displays the contents and options related to network .
Used to show other systems connected to this computer.
drives
Common
tasks
RECYCLE BIN
•
•
It is system folder, which contains the deleted files and folders from
computer.
Which can be restored.
MYCOMPUTER
It is a system folder that contains all drives, to which our computer is connected.
It also connects to CONTROL PANEL, etc.
•
•
•
•
•
•
•
•
Status bar
DRIVES: it lists all drives of system, as C:, d:, e: etc Removable disks.
CD or DVD drives connected to system.
TITLE BAR: shows the title of opened window
CONTROL BOX: it consist of Minimise button, Maximize button, CLOSE button.
MENU BAR: it has menus as FILE, EDIT, VIEW, TOOLS, HELP
ADDRESS BAR: shows path of opened window
STANDARD TOOL BAR: Shows the most used button shortcuts.
STATUS BAR: it shows some important status of window.
Source: Pradeepkumar. K.
Video device
ICONS:
•
•
•
These are picture which represent different application, or shortcuts of programs,
On clicking on ICON it opens specified application.
CREATING ICON SHORTCUT:
•
OPEN REQUIRED APPLICATION
•
RIGHT CLICK ON IT
•
CLICK ON “CREATE SHORTCUT”
WEB SOURCE: www.pradikshana.weebly.com
33
FUNDAMENTALS OF COMPUTER
•
B.Com–II sem.
DELETE ICON OR SHORTCUT:
SELECT ICON PRESS DELETE BUTTON
START MENU:
⇒
OPTIONS AVAILABLE ARE
PROGRAMS:used to open
applications
MY DOCUMENTS: for
document folder
MY PICTURES: opens picturs
MY MUSIC: opens music
folder
MY COMPUTER: opens all
drives and devices.
MY NET PLACES: opens
network settings.
CONTROL PANEL: for
settings
SETTINGS: for settings
PRINTERS: opens printer
settings
HELP: for offline help
SEARCH: for searching files
RUN: to open applications
Delete folder: (select & press DEL key)
1. Select desired FOLDER
2. Press DELETE button on KEYBOARD
3. It asks a message for confirmation
4. Say YES
Rename folder: ( press F2 key)
1. Select folder
2. Right click on it
3. Select RENAME
4. Change the name
Open folder: ( ctrl + O)
1. Double click the desired folder OR
2. From menu FILE & select OPEN & browse the desired folder
Creating file:
1. Move to desired directory
2. Click on File menu
3. Click on NEW submenu
4. Click on desired type of file
5. Specify name for file
Delete f file:
1. Select desired File
2. Press DELETE button on KEYBOARD
3. It asks a message for confirmation
5. Say YES
Rename file:
1. Select file
2. Right click on it
3. Select RENAME
4. Change the name
Open file:
1. Double click the desired folder OR
2. From menu FILE & select OPEN & browse the desired folder
Move file: ( or CUT file)
1. Select desired file
2. Right click on file, select CUT( ctrl + X shortcut)
3. Open destination area, & Right click
4. Select PASTE(ctrl + V shortcut)
NOTE: CUT & PASTE moves the file
COPY & PASTE copies the file and creates a duplicate of same.
WORKING WITH FILES AND FOLDERS:
Creating folder:
(1) Move to desired directory
(2) Click on File menu
(3) Click on NEW submenu
(4) Click Folder
(5) Specify name for file
Source: Pradeepkumar. K.
ACCESSORIES
This option is available in START → ALL PROGRAMS → ACCESSORIES
The option under this are
1. ACCESSIBILITY:
i) MAGNIFIER: is used for zooming the onscreen items.
ii) NARRATOR: is used to get text to voice programs, which gives text guide
iii) ON SCREEN KEYBOARD: this displays on screen “keyboard”.
WEB SOURCE: www.pradikshana.weebly.com
34
FUNDAMENTALS OF COMPUTER
iv) UTILITY MANAGER: used to configure all accessibility tools.
ENTERTAINMENT:
i) VOLUME CONTROL: displays master volume control dialog box.
ii) SOUND RECORDER: Is used to record sound by mic.
3) ADDRESS BOOK: it displays address book , which stores address and other details.
4) CALCULATOR: it opens calculator for calculating.
5) COMMAND PROMPT: it is MS-DOS environment.
6) NOTEPAD: is a text editor software.
7) PAINT: is a simple graphics editing software.
8) WORDPAD: is a rich text editing software.
9) COMMUNICATION: It opens communication related tools. as
i) HYPER TERMINAL: it is a program used to connect to other computer.
ii) NETWORK CONNECTION: displays network connections
iii) REMOTE DESKTOP WIZARD: used to share desktop remotely.
10) SYSTEM TOOLS:
i) BACKUP: is used to backup system data
ii) CHARACTER MAP: shows all characters of system
iii) DISK CLEANUP: is used to free disk space.
iv) SCAN DISK: it is used to scan errors of disk.
v) SYSTEM RESTORE: is used to set setting to earlier time.
B.Com–II sem.
2)
MENU BAR
CONTROL BOX
TOOL BOX
DRAWING AREA
TITLE BAR
COLOR BOX
STATUS BAR
CONTROL PANEL:
This is a system folder, which lists all system settings.
Steps: START → CONTROL PANEL
Settings under this are,
1) Accessability options: is used to change settings of keyboard, mouse, display, sound.
2) Add hardware: is used to add new H/W to computer.
3) Add/Remove Programs: used to add new program or remove installed program.
4) Date and Time: used to set time or date of system.
5) Display: used to change the display related settings.
6) Folder options: displays folder related options
7) Fonts: lists all fonts installed in system
8) Mouse: used to set mouse related options.
9) Keyboard: used to change keyboard settings.
10) Printer & Faxes: used to add or remove printer or fax machines
11) Power management: setting related to power schemes.
12) User accounts: used to add or delete users, their password etc
13) Sound & Audio devices: used to change how sound signals are used
14) Mail: used to setup services related to mail.
15) Regional & language options: used to set language of system
TOOL BOX
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
13)
14)
15)
MS PAINT
16) ROUND RECTANGLE: draws rounded rectangle
It is a simple graphics editing software, comes with windows operating system.
Steps to open:
START → PROGRAMS → ACCESSORIES → PAINT
Source: Pradeepkumar. K.
FREE FORM SELECT: used for selecting freely
ERASER: used to erase
PICK COLOR: used to pick color
PENCIL: used for drawing with pencil
AIRBRUSH: used to spray color
LINE: used to draw straight line
RECTANGLE: used to draw rectangle
ELLIPSE: used to draw ellipse or circle
SELECT: used to select
FILL WITH COLOR: used to fill with color
MAGNIFIER: used to zoom the diagram
BRUSH: used to paint by brush
TEXT: used to type text.
CURVE: used to draw curved line.
POLYGON: used to draw polygon
WEB SOURCE: www.pradikshana.weebly.com
35
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
DESKTOP & ITS COMPONENTS
1)
2)
3)
4)
START BUTTON: allows to access all programs
DEFULT ICONS: these are only icons which are available on desktop, when computer is
freshly installed with OS.
TASK BAR: bar which is available on desktop, which has some parts such as
•
Minimized applications,
•
Notification area: which allows to set date and time.
•
Start button.
•
Quick launch buttons.
SHORTCUT ICONS: which are created to open program, directly from desktop.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
36
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
RFC-822 ADDRESSING:
Its an addressing format for emails. It contains 2 parts local and domain parts as: username@domain
name: ex: pradeep_kurdekar@rediffmail.com
ELECTRONIC MAIL(UNIT III)
COMMON E MAIL SERVICE PROVIDERS:
Definition: Electronic Mail is mailing system for sending and receiving messages electronically
WORKING OF E-MAIL
Email allows to create, send, and receive messages from one system to other system. An email
contains USER AGENT, MESSAGE STORE, & MESSAGE TRANSFER divisions.
1)
USER AGENT: (UA): it allows to generate the actual message or mail. It
involves all user tasks such as typing, editing, sending new messages,
viewing letters, forwarding, replying, etc INBOX, OUTBOX, DRAFTS,
THRASH, SENT folders are helpful here.
2)
MESSAGE TRANSFER AGENT ( MTA): This is responsible for routing the
mails to their destination. Collections of interconnected MTAs form a
message transfer system. Message received from originator is delivered to
MTA by MTS.
3)
sender
•
MESSAGE STORE: (MS): here electronic mail can be stored till the recipient
picks it up.
U.A.
M.S
M.T.A.
M.S
.
U.A.
X.400 based message handling system supported by OSI standards.
2)
System Mail Transfer Protocol (S.M.T.P.)
basis with objective of enabling a standard message format .
X.435 Message Handling System: it helps in business communication as EDI.
Simple Mail Transfer Protocol (SMTP): it is member of TCP/IP protocol, that governs the
Source: Pradeepkumar. K.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
EASY TO USE: sending and receiving message is easy
HIGH SPEED: fastly it sends the messages.
HUGE SPACE: save lots of mails in the inbox
BULK MESSAGING: single message can be sent to many users.
TIME SAVING: easy use and instant transfer saves the time.
LOW COST: saves the money. As mailing is free of cost.
VERSATILITY: many kinds of messages including multimedia can be transferred.
ACKNOWLEDGEMENT: suddenly we get the delivery or pending message.
ADDRESS BOOK: can store address need not to remember.
ACTIVE ALERTS: we even can get messages on mobiles.
DIS-ADVANTAGES OF EMAIL:
1)
2)
3)
4)
5)
6)
Harmfull virus or data may be sent.
Un necessary data and messages may irritate the user.
Physical things can not be sent.
Must use email regularly.
Long day gap may delete or blocks the mail account.
If password is stolen, there may be chance of data miss use.
receiver
1)
X.400 Message Handling System: it enables users to exchange messages on a store & forward
exchange of electronic mail between MTAs. This protocol is used in TCP/IP networks for
transferring email between end user & mail servers.
ADVANTAGES OF EMAIL:
CREATING EMAILS
Two most popular e-mail system are:
1)
Gmail.com, yahoo.com, rediffmail.com, msn.com, hotmail.com, india.com, etc.
First have the access to internet with all basic requirements( as PC, NET connection,
I/O device)
2) Open the web browser( Firefox, Chrome, internet explorer etc)
3) In address bar type any desired email provider web address.( ex: www.yahoo.com,
gmail, rediffmail, etc)
4) Find the option to create new email ( ex: sign up, create mail etc)
5) It opens detailed application form
6) Fill details such as FIRST NAME, MIDDLE NAME, LAST NAME, DOB, MOBILE
NUMBER, ADDRESS,
7) Enter the email address of your wish in USERNAME@DOMAIN.COM format.
8) Usually user name is in lower cases.
9) Enter password, Re- confirm password.
10) And click on “SUBMIT” button, further details may be asked enter duly.
11) Mobile confirmation, photo upload may be also asked.
12) Refer below figure.
WEB SOURCE: www.pradikshana.weebly.com
37
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
SENDING MAIL:
•
•
•
OPENING MAIL BOX
1)open web browser
In mail box we have options to create mails.
Select “COMPOSE” or “WRITE” mail option.
( Below diagram shows complete idea of an mail box.)
2)enter web address of
your mail provider
3)now find LOG IN or
SIGN IN option
4)enter Username &
password
TO:
CC:
BCC:
SUB:
Compose
button
5)if data is correct, it
opens the mail box
Received
mails
6)it will have all options
related to emailing.
As inbox, compose,
mail, draft etc
folders
Send button
•
•
•
•
•
Fig: Creating e-mail
Source: Pradeepkumar. K.
•
•
•
Attaching files
It open a compose box with TO field, CC field, BCC field, mail area, send button, attach button,
and other options.
Here TO: is recipient to whom we want to send mail
CC: carbon copy (used to add multiple recipients list, but all people will know to whom same
message has been sent )
BCC: Blind Carbon Copy(used to add multiple recipients list, other people will not come to
know to whom same message is sent)
SUBJECT: add subject of mail.
Message Area: here we write the mail text.
If we want to attach file, then follow these steps
1. Prepare the file which you want to send. For ex: ORDER.XLS,
LETTER.doc,PHOTO.jpg etc
WEB SOURCE: www.pradikshana.weebly.com
38
FUNDAMENTALS OF COMPUTER
2.
3.
4.
5.
•
•
•
B.Com–II sem.
Click on attach button ( usually a pin symbolic)
Now it opens a FILE UPLOAD box.
Select required file.
If multiple files has to be uploaded then follow steps 2-4 repeatedly. (MAX 25 MB can
be uploaded)
6. Finally say DONE.
7. It will add your files to mail.
Now make any other changes required.
Finally click on SEND button.
A copy of sent mail will be saved in your sent folder
INTRODUCTION TO
INTERNET (UNIT IV)
Defn: it stands for : INTERconnectedNETwork
“Network of networks” or “ interconnection of computer networks through communication
systems where information flow is controlled by some protocols”
READ,FORWARD, DELETE
1)
2)
3)
Open mail box, go to INBOX, click on MAIL to read mails.
Select FORWARD button to forward selected mail.
Select mail, & click on DELETE button to delete mail.
History of INTERNERNET
First it was developed by US army as ARPANET(Advanced Research Project Agency Network).
“Tim Berners Lee” is called as Father of Internet.
Internet in India
Its started in 15th August 1995 by VSNL with speed 56 Kbps
Internet Organization &Committees
1. ISOC(internet society)
2. IETF(internet engineering task force)
3. IAB(internet architecture board)
Functions of IAB
Reviewing internet standards.
Managing the publication process.
Performing strategic plan for the internet.
Acting as an international technical policy liaison & representative.
Resolving technical issues that cannot be treated within IETF, IRTF
National organizations:
The ministry of information & broadcasting.
Communication and IT.
National informatics Centre(NIC).
Internet & Mobile Authority of India.
Basic Terms of NET
•
HTML(Hyper Text Markup Language)
Its formatting language used to design the weg page.It’s a protocol used to access the web
contents that are linked to hyper links on web page.
•
HTTP(Hyper Text Transfer Protocol)
Is protocol which helps to access hyper text& transfer.
•
Hyper TEXT: is underlined linkable text.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
39
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
•
Home page:
The first page of any web page. It links to all other pages of the web site.
•
Website:
Collection of web pages makes website. Which is placed on server and can be accessed any
time.
•
Protocol:
Its set of rules or regulations used for communication, data transmission etc. each protocol
has its own set of rules and task.
Eg TCP/IP , SMTP etc.
•
TCP/.IP: Transmission Control Protocol / Internet Protocol
Is most common reference to internet . its responsible for end to end transmission.
•
Upload:
The process of transferring data from private system to public server or net user can
upload data on net.
•
Download:
The process of receiving data from other system to our system. We can download
software,music, etc.
•
Gateway:
A special software or hardware which allows different electronic networks to communicate each
other on internet. It connects different networks.
•
DomainName:
Its mechanism for providing addresses for computers on the internet. These are of two forms 1)
human understandable 2) machine understandable.
Eg: www.google.com, www.kud.ac.in etc
GEOGRAPHICAL DOMAINS
Name of country domain name
India
.in
United States
.us
United Kingdom
.uk
Etc
INTERNET SERVICES:
⇒E-MAIL
⇒WORLD WIDE WEB
⇒SEARCH
⇒TELNET
⇒FTP
⇒CHAT
⇒NEWSGROUP
⇒BLOG
⇒SOCIAL NETWORK
WORLD WIDE WEB:
Its large collection of web sites, interconnected by HTTP, FTP and other protocols.
Its also known as “web”, “w3”, “www”
FILE TRANSFER PROTOCOL(FTP):
It’s helps in file transferring across the internet from one computer to other.
To download , to upload , to send , to receive we need compulsorily FTP.
•
Sub Domains:
These are part of domain name which used to classify the geographical or types of
networks.
These are two types 1) Geographical and 2) Non- Geographical
Eg. .com, .org, .net etc
TELNET:
It’s a protocol that allows our computer to logon to a remote computer and use that computer as if we
are physically present at that terminal.
It helps one computer to communicate with other computer.
Remote access is possible .
•
Domain Name System(DNS):
Is a database of domain names and their related IP’s .
A DNS server converts the name into its equivalent IP address.
NEWSGROUP:
These are internet discussion group devoted to specific topics. In which people can post comments or
information.
NON-GEOGRAPHICAL DOMAINS
DOMAIN TYPE
PURPOSE
1. .COM
used for COMMERCIAL purpose
2. .net
used for NETWORK related purpose
3. .org
used for NON-COMMERCIAL
4. .edu
used for EDUCATION purpose
5. .gov
used for GOVERNMENT purposes
6. .mil
used for MILITARY purposes
Source: Pradeepkumar. K.
EX: www.facebook.com
EX: www.satyam.net
EX:www. htvss. Org
EX: www. brtcollege. Edu
E X:www. nasa .gov
EX: www.af.mil
VIDEO CONFERENCE:
Its two way communication between people at different places with the help of video.
Here people see faces of each other on video screen an through multimedia.
Some special equipments such as audio, video and multimedia devices are required.
CHATTING:
It’s a form of interaction online. It allows us to communicate at real time, even we stay far away. As
we use phone for calling in same manner we can chat on time with text messages.
Some chatting providers are msn messenger, yahoo messanger, indiatimes, rediffmail, facebook etc.
WEB SOURCE: www.pradikshana.weebly.com
40
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
INTERNET RELAY CHAT(IRC):
It’s a series of networks that enables us to chat in real time with other people in other parts of the
world through internet.
When we talking on IRS whatever we type is instantly transmitted around the user who are online.
IRS is multi user, multi channel network.
MESSANGER SERVIECE:
This is similar to chatting service but in a restricted manner. Only some predefined friends can chat
with each other, not others here.
Eg: facebook messager, rediffbol, yahoo messangers.
BLOG:
It’s a collection of thoughts , ideas, facts quotes etc. posted on website.
The term blog came into existence in 1991. Its short form of web blog. Blogs are usually maintained
by blog owners.
Some blog sites are: blogger.com, tumblre.com , wordpress.com, squarespace.com posterous.com
etc.
GOPHER:
It’s a first web browser.
Its the web application or a protocol service or browser that was used to distribute, search on the
internet.
It was created by Paul Linder and Mark P McCahil in 1991.
It was showing the menus or list for linking.
Using gopher the well organized files can be brought from servers all over the world.
Gopher is well suited for text based information access.
Later “Hypher Gopher ” was developed to display the graphics on web page
WIDE AREA INFORMATION SERVER(WAIS):
WAIS is a client server text searching system that is used to search index databases on remote
computers. WAIS provides an interface for answering questions posted by a user on the information
in large databases which may physically remote from one another and the user.
WAIS was developed as a join project of Thinking Machines, Apple Computer, Draw Jones, KPMG
Peat Marwick in 1989. Since 1989 WAIS servers have been established in the US an other countries.
SOCIAL NETWORKS:
This is latest popular internet service that resembles news group and chatting. In this service a user
can become member of a social network site and can create his own profile or account. Social
networking site provides a platform to project oneself. People can find friends, create groups, etc..
Generally these sites are linked to email or phone no. the sites offer to share photo, albums,
comments, messages videos, etc.
Some social networking sites: facebook, nimbuzz, orkut, twitter etc.
CONNECTING TO THE INTERNET:
⇒ REQUIREMENTS:
•
Computer with serial or parallel port.
•
Modem
Source: Pradeepkumar. K.
•
•
•
Telephone line
Internet service provider
Web browser
MODEM:
it’s a hardware device, which is connected to a computer either as an external or internal device.
MODEM stands for Modulator and Demodulator.
Modulation is the process of converting digital electronic data into analog signals that can be
transmitted through telephone lines.
Demodulation is process of converting analog signal into digital signal.
INTERNET SERVICE PROVIDER (ISP)
An ISP is the” Software stored in a high speed 24 hour online PC that has facility to read
requests sent by the remote client and to send required webpage back to the user computer”
Its run by a group which provides access to user on pay basis.
Eg: BSNL, VSNL, MSN, Sathyam Reliance Infocom, etc.
WEB BROWSER:
Its software that opens web pages and display them in proper manner.
It understands URL and provides a graphical interface.
Eg: internet explorer, netscape navigator, Hotjava, opera , Mozilla’s Firefox, Google Chrome, etc.
HOW TO CONNECT PC TO INTERNET?
Follow the below steps
1) We need a standard modem, an active phone line
2) Then create link a as below
•
Click start button, point to program- accessories-communication and click new connection
wizard.
•
Follow the instructions in the wizard and provide details like type and method of
connection.
•
Click finish button to close. Now we will see dial up icon on desktop.
•
Click this dial up connection to connect.
•
Click dial button , automatically system gets connected.
•
Now start using the internet.
TYPES OF INTERNET CONNECTION:
1) DIAL UP CONNECTION
2) BROAD BAND CONNECTION.
⇒DIAL UP NETWORKING:
The dial up connection contains analog and digital communication method
a) Dial up connection: it is most common and widely used method of connecting. This service
is actually a low speed method of connecting to internet through an analog telephone line.
There are 3 kinds of modems available for dial up- internal, external, and onboard.
WEB SOURCE: www.pradikshana.weebly.com
41
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
b)
ISDN( integrated services digital network):
ISDN service actually involves a high speed digital telephone line installed by any
telephone company.
ISDN connection is much faster than normal dialup connection.
ISDN may have internal or external modem.
BROADBAND CONNECTION:
Broadband is high speed network connectivity service allowing data flow of 256Kbps of
higher.
Broadband service includes DSL modem or cable modem as follows
a) Cable connection: it uses a broadband connectivity device used by cable television
Infrastructure. It is capable of exchanging high capacity of data. External or Internal
adapter is required.
b) Digital Subscriber Line(DSL) Connection: It is also kind of broadband connection
involving DSL modem and Standard telephone line.
c) Asymmetric Digital Subscriber Line(ADSL): It is a high bandwidth digital transmission
technology that uses existing phone lines and also allows voice transmission over the same
line.
INTERNET APPLICATION OR USES
•
E-Shopping is possible.
•
E-fund transfer or online banking can be done.
•
Find the information about any topics.
•
Communication, mailing, chatting is possible.
•
Download or upload the required data.
•
All field all data can be accessed.’
•
Web site can be launched.
•
We can book train, airways, movies, rooms, etc online only.
•
We can apply for any work online.
•
Online help can be taken from the experts about any topics.
INTERNET SECURITY
•
Better to use firewalls.
•
Using good antiviruses.
•
Using passwords.
•
Filter and block unwanted sites.
•
Enforcing cyber acts.
•
Using cryptography
“SEARCH ENGINES” (UNIT V)
⇒ SURFING:
Defn: Surfing is process of working with WWW or navigating the web pages for some specific
reason.
Hyperlinked pages are main object of surfing.
Ex: opening & searching information in Wikipedia, watching youtube videos, etc.
⇒ Search Engines
These are web pages which helps the user to get information about any thing what user wishes.
These usually have the search tool, which accepts a word or phrase or query for searching. And
searches details in webpages about it.
Some search engines are:
Google.com, ask.com, yahoo.com, khoj.com, rediff.com, amazon.com, etc.
⇒ Indexing
It is the process of creating indexes to help researches for finding information easily.
Web indexing: is the process of creating a list of keywords or phrases present in a website to make
search easy for search engines.
Meta data: is structured information which describes, locates, makes easier to retrieve
information.
It is also known as data about data.
⇒
⇒
1)
2)
3)
⇒
1)
2)
3)
4)
5)
⇒
1)
2)
3)
Types of metadata:
Descriptive metadata.
Structural metadata.
Administrative metadata.
Functions of metadata:
Resource discovery: is which helps to find out resources.
Organizing web based resources.
Promoting interoperability: some information generated are understood by both humans
and machines.
Digital identification: metadata uses digital identifier to locate resources.
Archiving and preservation: metadata keeps data for future use.
Categoris of metadata
Technical metadata: it defines the data model & data structure. Such as display, reports
etc.
Business metadata: deals with the type of data, its location, its purpose, its meaning.
Process metadata: deals with the operations. Such as start time, end time etc.
⇒ Some search engines
1) Yahoo!
It’s a popular search engine, launched in 1994 by jerry yang & david filo in USA.
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
42
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
It provides: email service, search, finance, advertisements, entertainment, social media, etc.
2) Google:
A very famous and widely used search engine in the world.
Larry page & Sergey Brin of USA developed a search engine as BACKRUB in 1996.
In 1997 same was named as Google( name ref by GOGOL= 1& 100 zeros)
Features:
•
Allows user to search on different criteria.
•
A word, phrase, images, maps, news, videos, shoppings, books,places, blogs can
be searched.
•
It supports many indian languages as kannada, hindi, marati, telugu etc.
•
Allows advertisements.
•
Allows mail service(known as gmail).
•
Allows social networking.
•
It supports even handheld systems as mobiles.
•
Offers a browser “google chrome”.
•
Google earth is application of google to route earth maps.
SERVICES OF GOOGLE:
1)google Alerts: provide google e mail notification services, to send messages.
2)Google Finance: provides financial services and assistance.
3)Google news: provides automated news service.
4)Gmail: it is free email service used very popularly.
5)Picnik: it is google’s online photo editing service.
3)
4)
5)
⇒
Khoj
Its an Indian search engine. Developed by sify technologies ltd.
It offers searching information based on the www, sify, finance, celebrities, local, friends,
jobs, educations, movies, reviews, blogs, travel, etc.
It supports many Indian languages.
India4you
It’s an authentic online marketing website for Indian handicrafts.
Customers can buy articles using electronic payment systems.
It has mission called SRCM to promote Indian handicrafts.
The product categories available here are: clothing, dolls, decorative items, Indian
ethnics, jewelry, paintings, pooja ornaments, handmade cards etc.
Youtube
It’s a popular video search engine.
As google searches text and image youtube searches videos for given phrase or word.
Here anybody can upload or share or download the available video.
For downloading you must use application known as “youtube downloader”.
SOME IMPORTANT WEBSITES
1) Related to education:
www. schooleducation.kar.nic.in: Karnataka state edu services.
www.ncert.nic.in :
National council for education training & research
Source: Pradeepkumar. K.
www.cbse.nic.in :
www.ugc.ac.in :
www.kud.ac.in :
www.aieee.edu :
www.aicte.ernet.in :
www.aima-ind.org :
central board of secondary education
University Grant Commission.
karnatak university, dharwad.
All India Engineering Entrance Examination.
All India Council of Technical Education.
All India Management Association.
2)
Related to companies:
Amazon.com, rediff.com, yahoo.com, onsale.com, deil.com, smarts.com, etc.
3)
Related to library:
www. nationallibrary.gov.in: India govt. website
www. Myonlinelibrary.co.in:
www. Vlib.org: virtual library
www. Kannadalibrary.com: kannada documents
Related to stock market:
www. Nseindia.com, www. bscindia.com, www. nasdaq.com, etc.
4)
Related to News papers:
♣ Kannada: www. epaper.samyukthakarnataka.com, www. prajavani.net., www.
sanjevani. Com, www. vijaykarnataka.indiatimes.com, www. udayavani.com, etc
♣ Hindi: www. bhaskar.com, www. amarujala.com, www. jagran.com, www.
dainikbhaskar.com, etc,
♣ English: www. timesofindia.com, www. thehindu.com, www.
indianexpress.com, www. deccanherald.com, etc.
5)
⇒ Online Encyclopedia:
www. britanica.com, www.encyclopedia.com, www. worldbook.com, www. Wikipedia.org, www.
reference.com, www. indiavideo.org, etc.
⇒
Britanica.com
Its an online Encyclopedia launched in 1999. Its headquarters is at Chicago, USA. It’s a
global leader in educational publishing and its products are found in several media such as
the internet, cell phone, books, etc. for learners of all ages.
⇒
Thefreedictionary.com
The worlds most popular dictionary that offers dictionary services in 14 languages. It
covers all field information.
⇒
Wikipedia.org
It’s the most popular, multilingual , web based free content encyclopedia, operated by the
Wikimedia foundation. And is based on openly editable mode. In this site any body of the
world can edit the content and share it. Its almost considered as worlds top 10 web site for
information seeking.
Brainpop.com
⇒
WEB SOURCE: www.pradikshana.weebly.com
43
FUNDAMENTALS OF COMPUTER
B.Com–II sem.
Its an animated educational site for kids founded in 1999, that is aligned with USA state
education. It has about 1000 short animated movies for students which covers subjects like
science, English, mathematics etc.
ARPANET
ISOC
IETF
HTML
HTTP
SMTP
ABBREVATIONS
Advanced Research Project Agency NETwork
Internet SOCiety
Internet Engineering Task Force
Hyper Text Mark up Language
Hyper Text Transfer Protocol
Simple Mail Transfer Protocol
TCP/IP
FTP
ISP
ISDN
DSL
POP
Transmission ControlProtocol/ Internet Protocol
File Transfer Protocol
Internet Service Provider
Integrated Services Digital Network
Digital Signal Line
Post Office Protocol
CC
Bcc
Carbon Copy
Blind Carbon Copy
9) expln 5 I/P devices ,
10) expln 5 accessories in windows,
11) explain internet & uses ,
12) creating e-mail and attaching file case study
13) write notes on OMR, Google,
control panel
☺☺☺ good luck ☺☺☺
♣♣♣♣♣♣♣♣♣♣♣♣
Question paper : 2013
I answer for 2 M
1)Define computer, 2) write any 2 impact printers, 3) what is s/w
4) any 2 o/p device
5) what is Recycle bin,
6) what is MODEM, 7) Rqrmnts of internet,
8) any email providers,
9) expand CC & Bcc,
10) what is Search engine, 11) any 2 stock market webs,
12) how to create new folder
II answer for 5 M
2)charcters of computer,
3)Explain Application s/w ,
4) Explain desktop,
5) Explain internet browser,
6) expln email benefits,
7) explain facebook, orcut
III answer for 15 M
8)expln Generation,
Source: Pradeepkumar. K.
WEB SOURCE: www.pradikshana.weebly.com
44
Download PDF
Similar pages