First Semester (PGI ABM) Course No.:ABM-513 (Computer for Managers) Course Teacher: Prof. A.D. Kalola INTRODUCTION TO COMPUTER Definition of Computer : Computer is an electronic device, which can input, store and manipulate data and output information in the desired from. A computer, small or big, is basically a device used for processing of data (numbers) and text (words). It performs essentially, Receives data or text (as instructions) Processes data (as per the instructions) Produces results (information) The above three operations are in a sequence and is known as INPUT-PROCESSING OUTPUT (IPO) cycle. It is also called Data Processing cycle. INPUT PROCESS OUTPUT Credit : 1 + 1

Characteristics of computer : 1. Speed 4. 2. Accuracy 5. 3. Versatility 6. Characteristics of computer:1.

Storage and retrieval of information Consistency Automation

Speed: Speed is the rate at which a computer can process instructions per

second. Computer can perform millions of calculations and operations in a second.2.

Accuracy: Computers are not only fast but it always gives accurate result Versatility: Most of the digital computers are general purpose computers

provided programs and data should be correct. It gives errorless results.3.

because they operate with numbers. So it can do any types of work provided the data and programs should be correct.4.

Storage and retrieval of information: Computer can store huge amount of

information. Such information can be retrieve within a fraction of second for further use.

1

5.

Consistency: When performing highly repetitive work, like human being, do

not become bored or tired as lose concentration. If it has to compute a million numbers, it will compute each with equal diligence. 6. Automation : Computer is much more than a calculator hence a program is in the computer memory, the individual instructions are transferred, one by one, to the control unit for execution till the end. Hence the human operations are very limited.

Uses of Computers : 1. Many calculations that were previously beyond contemplation have been now become possible due to computers. For example, the landing on the moon and the despatch of different satellites would not have been possible without the help of the computers. 2. The automation that has now been achieved in many industries and business organizations is due to the use of computers. In addition, this automation has helped in manufacturing and processing industries, airlines and railway reservation system, transportation and banking systems etc. 3. Modelling and simulation is another area where computers are increasingly used. They are used in physical science, medicine, astrology, meteorology etc. 4. Business and commercial organizations need to store voluminous records and use them for various purposes, such as inventory control, sales analysis, payroll, accounting, management reports. A computer can store and maintain the files, sort, merge, update, delete and produce them whenever necessary. 5. With the introduction of word processors, computers are now extensively used in offices in clerical and managerial staff with increased efficiency and accuracy 6. Computers are also used widely in libraries, documentation centres, employment exchanges, police departments, hospitals and other establishments. They are also used in game and Olympic. 7. Computers are also used in teaching. This process is known as computer-assisted learning (CAL). Here, learners can sit at a typewriter, like terminals and communicate directly with a computer. This will help the learner to learn at his own time and speed.

2

8. Another type of learning used with the computer is computer management learning (CML). Here computer can store students responses, evaluate his performance and then direct him to the next learning unit. History and evaluation of computers : Around 3,000 B.C. the Chinese developed a mathematical device called ABACUS used for to facilitate arithmetical computation. ABACUS used beads strung of wires to aid arithmetical computation and is believed to have been in use till recently. The first mechanical Computer called Analytical Engine designed by Charles Babbage between 1830 and 1850 marked the birth of computer age. This was the first mechanical computer capable of performing basic arithmetical functions. Charles Babbage designed his Analytical engine around five components, namely. a STORE in which to hold numbers an ARITHMATIC unit to performs arithmetical operations a CONTROL unit to control and coordinate various activities in the correct sequence an INPUT device to pass both numbers and instructions into the computer an OUTPUT device to display the results obtained from the calculations. Electronic Digital Computers : The first electronic calculator called ENIAC (Electronic Numerical Integrator And Calculator) was developed by Dr. John Machauly, J Presper Eckert and their associates at University of Pennsylvania between 1942 and 1946. This computer weighted 30 tonnes, contained more than 18,000 vacuum tubes and required more than 1500 square feet of floor place. It could perform 5,000 addition in one second. John Von Neumann, renowned as one of the worlds great mathematicians, gives the idea of Stored Program to replace the cumbersome and complicated wired control panels of ENIAC one of the first computers using this concept was built by the Mooney school Personnel and the Ballistics Research Laboratory of the U.S. army in 1948, at the university of Pennsylvania. This computer was called EDVAC (Electronic Discrete Variable Automatic Computer) and had a storage capacity of 1024 words of 44 bits each. Remington Rand built the first commercially available computer UNIVAC (UNIversal Automatic Computer) in 1951 was used by the U.S. Census Bureau. Generation of computers :

3

Distinguish between varying hardware technology is generation of computer. Based on the technology they are classified as first, second, third, fourth and fifth generation computers. Generati on 1st Gen. 1940-52 Electronic component Vacuum tubes e.g. ENIAC Comments/ Examples Vacuum tubes Large size, Use machine lang. were the only generated heat, instructions. ENIAC, electronic A.C. required, EDSAC, EDVAC components Unreliable UNIVAC, IBM-650 available constant maintenace Transistors Small size, less As above Development of e.g. heat generated, assembly lang. IBMIBM 1401 more reliable 162,CDC-3600, RCA501, IBM 1401 Integrated Even smaller Initially, Higher level languages Circuits on size, Even lower problems with were used for silicon heat generation, manufacture instructions. chips (IC) less power Development of required, even software side. IBMmore reliable, 360 Series, ICL-1900, faster still ICL-2900, PDP-11, HONEYWELL-6000 Series Large Hardware sizeRemarkable Scale very development of Integrated compactable, software side, Circuits Internal storage Development of netdeveloped capacity working,word (LSIC) increased processing INTEL-4004, APPLE Series I & II, DCMs TANDY,TRS-80,DCMs SPECTRUM-7 Very Large Japan and many countries are working on "Expert System" will Scale considerably the man-machine interaction would facilitate Integrated computer-aided problem solving with the help of organised Circuits information in many specialised area and Development using VLSIC ideas of artificial intelligence will be known as fifth Advantages Disadvantage

2nd Gen. 1952-64 3rd Gen. 1964-72

4th Gen. 1972-84

5th Gen. 1984 and above

First generation (1940-1952) : This generation computers were developed in the year 1945-46. These computers use vacuum tubes. Vacuum tubes as basic component for memory and4

CPU. It was made up of electronic valves. The first category of the computer was ENIAC. The first generation computers were more costly (expensive) and occupied more space. Vacuum tubes produce lot of heat and were prone to frequent fusing. Such computers afforded only very large organization. Second generation (1952-1964) : made up of semiconductors (transistors, diodes etc.,). some high level Computers were

So vacuum tubes were replaced by transistors. In this period

languages are also developed. BASIC, FORTRAN, COBOL. To store the program and data, magnetic disks were developed. The second generation computers which used transistors instead of vacuum tubes consume less power and are less expensive. Third generation (1964-1972) : In this generation the computers were made up of small scale integrated circuits (I.C) on silicon cheap. Later it was developed using medium scale integrated circuits with the capacity of main memory as much as 4 mega bytes. The speed of computing is one million operations per second. Due to IC technology significant reduction in size and cost. Fourth generation (1972-1984) : These computers were made up of large scale integrated circuits (LSIC). These IC, packing nearly 10,000 transistors are grouped in a single silicon chip, Known as microprocessor. These computers are classified as micro computers. The memory capacity is very high (more than 100 megabytes) Fifth generation (1984 onwards) These computers were made up of large scale integrated circuits (VLSIC). These computers use the technique called Artificial intelligence. It is a technique by which we make the computer machine to think by interpreting the information given to the machine and then producing the appropriate output. Size of these computers is very compact.

Classification of Computers : 1. DIGITAL Computer: It operates by counting numbers i.e. it operate directly on numbers expressed in binary numbering system. It represents information in discrete form (0s and 1s).

5

-

Digital computers produce more accurate results than analog computer. Perform complex and repetitive calculations rapidly and accurately. It storage large amount of data. Provide information in textual and graphical manner.

2. Analog computers: Operates on data in the form of continuously variable physical quantities such as pressure, temperature, revolutions, speed or voltage. An analog computer is essentially a measuring device. Examples are the automobile speedometer and the slide rule. Since the analog computer measures and compares quantities in one operation, it has no storage. It is derived from the Greek word ANALOG. 3. Hybrid Computers : A combination of digital and analog computers is known as hybrid computers. Types of Computer: Depending upon the cost and performance capability of machines, the computers may also classified as follows 1. 2. 3. 4. 5. Microcomputer Mini Computer Mainframe Computer Super Computer Laptop Computer (Note book)

1. Micro computer: A micro computer is the smallest general purpose processing system that can execute program instructions to perform a variety of task. Micro computer is cheap in cost and easy to use. It can be used for different application. Personal computers (PC) are the examples of micro computer. e.g. PC, PC-XT (Extended Technology), PC-AT (Advanced Technology), 386, 486, 586 Pentium.

2. Mini computer: A mini computer may be defined as small general purpose computer that is capable of handling large amount of data from multiple users working simultaneously. These systems are costlier than micro computer. It has large storage capacity, very fast (speed) in arithmetic operations and ability to support a greater variety of faster operating device as compared to PC.

6

PC system remains oriented towards single user whereas mini systems are usually designed for multiple users. 3. Mainframe computer: Mainframe computers are more powerful and costlier than mini computers. It possess the capability of handling a large number of application programs. It support hundreds of users at a time. Most of the packages designed in the past have been written for mainframe computer. All high level programming languages can be used on available for mainframes. 4. Super Computer: Super Computers are the most powerful and most expensive computers so far made. Only few of these computers are produced each year. The calculations needed in some scientific research and development area where simply can not do with out Super Computer. Generally, super computers are used in energy sector, space exploration and weather forecasting areas. In India, Centre for Development of Advanced Company (C-DAC), Pune has developed the super computer PARAM. Now-a-days less than 500 conventional super computers are available in the world.

Basic structure of Computers:

7

INPUT DEVICE

MEMORY UNIT CONTROL UNIT

OUTPUT DEVICE

ARITHMETIC and LOGIC UNIT (ALU)

CENTRAL PROCESSING UNIT or PROCESSOR (CPU) They are classifying in mainly three units. (1) (2) (3)(1)

Input unit Central Processing unit (CPU) Output unit INPUT Unit: Computers needs to receive data and instructions in order to solve any problem. Therefore through input unit, information are fed into the computer. The inputs are data, program or their related things. The keyboard, mouse, card, tape etc. are used as input devices.(2)

Central Processing Unit (CPU): It is the main part of computer system like

the heart or brain of human being. It interprets the instructions in the program and executes one by one. The three units, the memory, the arithmetic and logic unit and control unit, are collectively known as central processing unit. Arithmetic and logic Unit (ALU): It performs all the arithmetic and logical operations. Arithmetical operations are addition, subtraction, multiplication and division. Logical and relational operations are AND, OR, NOT, , , . This unit is capable of comparing two numbers and decides whether one number is less/greater/ equal to other numbers. Memory Unit: It is used to store the information like program, data etc. No any computation can take place in this unit. Control Unit: It controls and directs the transfer of program instructions and data between various units. It co-ordinates the activities of the input-output, arithmetic and logic unit and memory units by timing and directing the flow of informations from one unit to another.(3)

OUTPUT Unit: It is used to print /display the results which are stored in the

memory unit. Input devices:

8

(1)

Key Board : The most common input device is the keyboard. It is used to Punched Card Reader : Punched card is a input medium for computer.

input letters, numbers and commands from the user.(2)

Instructions and data punched on cards are transmitted into a computer through card reader.(3)

Magnetic Ink Character Reader (MICR) : MICR is an input device used to

read characters printed using a special magnetic ink. Cheque number and amounts written in magnetic ink are read by MICR. This ensures accurate data entry to the computer.(4)

Optical Mark Reader (OMR) : OMR is an input device used to read marks on

a paper form. These pre-printed forms are designed with boxes which can be marked in dark pencil or black ink. OMR converts these marks into electrical pulses which are transmitted to computers. OMR are used in objective type tests, mark surveys, population surveys etc.(5)

Optical Character Reader (OCR): OCR is an input device used to read any

text either in handwritten or printed form. The text is scanned by OCR and converted to a machine readable form. This text can then reformatted, stored and printed. It is expensive and used in situations where large quantities of documents (typed or hand written) are to be entered in the computer.(6)

MOUSE: Mouse is a small pointing device held in hand and pushed along a

flat surface. It can move the cursor in any direction. In a mouse a small ball is kept inside, when the mouse is moved, the ball rolls. This movement of the ball is converted into electronic signals and sent to the computer. Mouse is very popular in the modern computers that use windows application.(7)

Scanners: Under the control computer software, a scanner translates what is

sees on a page into a format the computer can use. This process is known as digitizing or scanning. Output devices: Output devices are used to get results from the computer.(1)

Monitor or Video Display Unit (VDU) :

Monitor provides a visual display of data. It looks like a television. It gives a soft copy of output. There are different types of VDU available. Monochrome Graphic Adapter (MGA) Very High Resolution Graphic Adapter (VGA) Colour Graphic Adapter (CGA) Enhanced Graphic Adapter (EGA)9

(2)

Printer:

The printer is output device which allows a hard copy of the output which can be stored for later reference. There are two types of printers. (A) Impact printers: In this printers image is created by pressing a typeface against an inked ribbon which makes mark on the paper (physical contact). These printers are DMP (Dot Matrix Printer), line printer and Daisy Wheel printer. i) Dot matrix printer: Printer may be of 9 or 24 pins with line width 80 or 131 columns. It prints 180 to 400 characters per second (CPS). ii) Line printer: It prints one line of information at a time. It speed is 300 to 1200 line per minute (LPM). Line printers are faster than DMP.iii)

Daisy Wheel Printer: It is a character printer. It prints character with the help of character wheel. It produced excellent quality output than above two printers.

(B) Non-Impact printers: Non-impact printers are those which print information without any physical contact with paper e. g. Laser printer, ink jet printer, plotter. i) Laser printer : This type of printers make the use of characteristics of heat. The method of printing the characters is some what similar to dot matrix, except that the impression is produced thermally. An electronically controlled laser beam traces out desired character to be printed on a photoconductive drum. The drum attracts an ink toner on the exposed areas. This image is transferred to the paper, which comes in contact with the drum. This printer prints 4 to 16 pages per minute. ii) Ink jet printer : This printer consist of a print head, which has a number of small hole or nozzles. An integrated circuit resistor can heat individual holes very rapidly. When the resistor heats up, the ink near it vaporizes and is ejected through the nozzle and makes a dot on paper placed near the head. Memory The computer needs a storage area for keeping its results for CPU or externally added. The basic unit of storage in memory systems is a bitable device, i.e. a component having two stable states. Conventionally these stable states are used to represent a zero or a one and hence the storage unit is known as BInary digiT or BIT. Since a bit can represent only two values, we need a group of BITs to store a meaningful instruction or data. The standard unit adopted for such group is eight and a group of eight bits is known as a byte. Using standard coding systems known as10

further

processing. This is called as memory. The memory can be placed as a part of the

(ASCII) (American Standard Code for Information Interchange) character (any keyboard character).

or EBCDIC

(Extended Binary Coded Decimal Interchange Code), a byte is used to store a The capacity of the memory is measured in Kilo-Bytes (KB), Mega-Bytes (MB) and Gigas Byte (GB). 1 KB = 1024 Bytes, 1 MB = 1 Million Bytes=1024 KB, 1 GB =1024 MB = 1024x1024 KB = 1 thousand Million Bytes Accordingly it can be classified into two types. They are 1) Primary memory or Main memory 2) Secondary memory or Auxiliary memory Primary memory The memory which is built as a part of the CPU is called the primary memory or main memory. While purchasing a computer, one looks desirably for the main memory capacity. Usually while specifying a computer, the capacity of the main memory is also given (like 256K, 640K where K= one kilo byte = 1024 bits). The main memory can be classified in to types as magnetic core memory and semiconductor memory. Random Access Memory (RAM) A read/write memory is called as random access memory. As the name implies, data can be read or written into this memory. To write the data, the address is placed on the address bus and the chip is informed that a writing operation is going to take place, by enabling the WRITE pin. Then the data is placed at the data bus which is then stored. Similarly to read the data, the address and the READ pin are enabled and the data is retrieved without disturbing the actual content. The data stored is said to be volatile, which means that once the power supply is removed, the contents of the memory are lost. Read Only Memory (ROM) It is possible to read the data stored in this type of memory. The data is stored by the manufacture of by the user by using special equipments. This is called programmable read only memory (PROM). The information stored in such memory can not be over write or erased and its content to be read only. These are termed as nonvolatile memories. This memory contains utility programs supplied by manufacturers. Difference between RAM and ROM Sr. No. 1 RAM ROM

The informations are stored Constructed by the manufacturer and retrieved by the Informations stored in this memory programmer's choice can not be modified by the programmer (in EPROM) and PROM modifications11

2 3

Permanent functions like sin x, cos x etc are stored for further uses 4 Simplest and cheapest type of memory 5 ROMs are expensive to change and produce in small quantities Secondary memory (Secondary storages) This is also called external or auxiliary memory. Since the primary storage (RAM) offers limited capacity and temporary, it is essential to have auxiliary or secondary storage where large volume of information can be conveniently stored for future retrieval. Generally program and data files are stored into this memory. The two types of secondary memory are (i) serial access memory It provides only a serial access to retrieve the information stored in it (e.g. magnetic tape) (ii) random access memory - It provides random information stored in it (e.g. magnetic disk) 1) Magnetic Tapes It is extensively used as secondary storage It permits the sequential storage and access and stor large amount of data. Magnetic tapes are plastic types coated with magnetic material such as ferrous oxide. The tape is divided into number of tracks. As the number of tracks increases the data storage capacity also increases. The records are stored in block forms and are separated by an identification gap called, Inter Record Gap (IRG) or Inter Block Gap (IBG). Hence the IRG is a gap that exists between two consecutive records stored in a magnetic tape. A standard tape reel is 2400 feet long and inch wide and stores 20 MB to 150 MB information. Information recorded in the form of binary digit 0s and 1s. 2) Magnetic Disk Since much time is wasted in reading and writing the data on the storage devices, there is a constant need for devices with less access time. With this end in view, magnetic disks are developed. A disk coated with magnetic material is used as the media in this type. A read, write head moves across the surface while the disk is kept constantly rotating the high speed. fixed disks or hard disk. (a) Floppy Disk - Also known as diskette.12

Volatile memory (i.e. information will be lost of the failure of power Used to store intermediate results Most complex and expensive memories Easiest to change

are possible Non-volatile memory

access to retrieve the

The disk is divided into number of tracks and

also into sectors. Magnetic disk can be categorised in two types viz., floppy disks and

It is a single flexible disk used for stored and retrieval purpose of information. The floppy disk have nearly 70 tracks on which information is stored with capacity of 3,00,000 to 5,00,000 characters. A magnetic head is used to record and retrieve the information. Disk are permanently sealed in a plastic jacket known as cartridge. When the disk is inserted in the slot of the floppy drive and locked, it is fixed on the hub, which rotates at a constant speed of 300 RPM. It is available in 8.0", 5.25", 3.5" diameters. Similarly there are different capacity drives also. Size Capacity Track Sector byte/second 5.25" 360 KB 40 9 512 DSDD 1.2 MB 80 15 512 DSHD 3.5" 1.44 MB 80 18 512 DSHD DSDD (double side double density) Fixed Disk (Hard Disk) In floppy disks, where one can keep changing the disks. In fixed disks are stacked together and they are not removable. They are also called Winchester or hard disk. The principle of reading/writing is same as floppy disks. As the number of disks are more, they have much higher storage capacity. As the disks are permanently fixed and enclosed, the speed at which the rotate is also high (in the order of 300 RPM i.e. 10 times that of floppy disks). This enables higher storage capacity and faster access.3) 4) 5)

Compact Disk (CD) : CD can store data upto 700MB Digital Versatile Disk (DVD) : DVDs can store data from 4.7 GB to 17 GB. Flash drive (Pen drive) : Use just like floppy disk. Available in different capacity 700MB, 1 GB, 2 GB, 4 GB

Program : The set of instructions/information arrange in some logic or sequence for a computer to perform any task is called program. software is a collection of computer programs, procedures and documentation that perform given set of tasks on a computer system or software is the set of instructions or data that can be stored electronically is software. The software are two types System software : The facilities for better utilization of system resources is called system software. Any operating system is example of system software. Application software : A software developed for specific needs is called application software. The financial accounting software, SPSS, MS Office are example of application software. Hardware : The physical components that form the computer are called hardware. Monitor, Printer, CD-ROM13

COMPUTER LANGUAGES / PROGRAMING LANGUAGES: As we know CPU executes instructions stored in main memory and these instructions will have to be in binary in the machine language of the CPU. However, it is difficult to give instructions in the machine language to solve even the simplest of our normal problems. We can express our problems batter in English like language. Considering this fact, the software developers have designed higher level computer language and developed translators which translate instructions given in higher language are difficult and developed translators which translate instructions given in higher languages into machine language (machine language being the level language). (1) MACHINE LANGUAGES: Machine Languages are written in the machine code. The computer can interpret and execute these codes directly. Each type of computer has a unique set of machine code. A program written in one machine language cant be executed on another computer. Also machine language are difficult and tedious to learn.

14

(2)

ASSEMBLY LANGUAGE : An assembly language uses mnemonic (symbolic)

codes rather than numeric codes (as used in machine language). For example, ADD or A used as a symbolic operation code to represent addition and SUB or S is used for subtraction. Memory locations containing data are given names such as TOTAL MARKS, TIME etc. As the computer understands only machine-code instructions, a program written in assembly language must be translated into machine language before the program is executed. A computer program referred to as an assembler does this translation. The assembly language is again a machine-oriented language and hence the program has to be different for different machines. The programmer should remember machine characteristics when he prepares a program. Writing a program in assembly language is still a slow and tedious task. (3) COMMON HIGH-LEVEL LANGUAGES : Many high-level languages have been developed during the last two decades. The most common high-level languages are FORTRAN, BASIC, COBOL AND PL/1. Although they are less efficient than the machine or assembly languages, they relieve the programmers of the tedious task of remembering numeric codes for storage locations, operations etc. In addition, these languages are easier to learn and use.

Commonly used high-level languages for various applications are : (1) FORTRAN (2) COBOL (3) BASIC (4) ALGOL (5) PL-1 FORmula TRANslation Common Business Oriented Language Beginners All purpose Symbolic Instruction Code ALGOrithmic Language Programming Laguage-1 etc.

The American National Standards Institute (ANSI) has also developed standard specifications for these languages. In addition to these a language called PASCAL (named after the scientist) was developed by computer scientist for structured programming. The language PROLOG (PROgramming LOGic) has become popular for artificial intelligence applications and the language C has become popular for developing applications involving the use of basic system resources. To be able to use any of these languages, we need to have the language translator software or say language processors. LANGUAGE PROCESSOR OR TRANSLATORS :

15

It is a system software which will translate a computer program written by into machine understandable form. This translation is done either through compilers or through interpreters. A COMPILER : is a translator which reads an entire program (called source program) written in a high level language and convert it into machine language codes (object program). AN INTERPRETER : is a translator which interpreters statement by statement any program written in a high level language. Booting up Computer : In computing, booting is a bootstrapping process that starts operating systems when the user turns on a computer system. A boot sequence is the set of operations the computer performs when it is switched on which load an operating system. OPERATING SYSTEM (OS) : OS is the most important system software and O.S. makes the computer to accept commands in English (rather than in binary, the native language of the machine), and execute them to offer various services. The services offered by O.S. include the acceptance of instructions and data from several types of input devices, present the results on various types of output devices, organize the storage space on auxiliary storage devices in the form of files, load the specified software from these devices into main memory and execute them, i.e. the basic operations required to work with different devices are all performed by O.S. Similarly several software packages can be stored on the discs/tapes can be executed by giving simple instructions to the O.S. In large computer system they also provide the multi -user working environment. On PCs the MSDOS (Micro Soft Disk Operating System) and MS Windows and on MINI the UNIX is the standard OS. Operating System : Operating system is a set of programs which helps the users to interact with the hardware. The user communicates their needs to the operating system in the form of commands and operating system performs the activities. OR The operating system (OS) is the first things loaded onto the computer, without the operating system, a computer is useless. The purpose of an operating system is to organize and control hardware and software so that the device it lives in behaves in a flexible but predictable way. The operating system is a interface between user and computer. There are so many operating system are available in a market:16

1. 2. 3. 4.

MS-DOS WINDOWS 95 / 97 / 98 / 2000 / NT / XP UNIX, ZENIX VAX, OS/2

Boot Also known as boot up, booting is the process of powering on a computer causing it to load the operating system or other platform. During the boot process the computer will perform a self diagnostics also known as a POST as well as load important data or programs to help in the operation of the computer. Warm boot One method of resetting a computer system that is already powered on, commonly used to recover from errors that cannot be recovered, or when a computer locks. A warm boot can be accomplished by pressing the CTRL - ALT - DEL keys simultaneously, or by selecting the restart command from an operating system menu. Warm boots run faster than turning a computer off and on again. Cold boot Also known as a hard boot a cold boot is a term used to describe the process of turning on the computer after it has been powered off. For example, when you first turn your computer on after being off for the night that is referred to as cold booting the computer. What is a computer virus? A computer virus is a software program that has been intentionally created to cause a user grief, spread to other computers, or destroy data on an individual's computer. To help prevent a computer from becoming infected by a virus, software developers have developed antivirus programs that stay active on the computer helping to protect it. It is important to realize that many computers do not come pre-loaded with these already installed and that if computers do come with these programs, the programs may expire within 90 days. How computer viruses are contracted In the past the majority of computer viruses were contracted from users sharing data using floppy diskettes. However, with the increased popularity of the Internet most computer viruses are contracted today through e-mail and by downloading software over the Internet or P2P sharing. What viruses may do to a computer Below are different issues you may experience when you are infected with a virus. Keep in mind that you also may be experiencing any of the below issues by another computer related issue and not a virus.17

Deleted files. Various messages in files or on programs. Changes volume label. Marks clusters as bad in the FAT. Randomly overwrites sectors on the hard disk. Replaces the MBR with own code. Create more than one partition. Attempts to access the hard disk drive, which can result in error messages such as: Invalid drive specification. Causes cross-linked files. Causes a "sector not found" error. Cause the system to run slow. Logical partitions created, partitions decrease in size. A directory may be displayed as garbage. Directory order may be modified so files, such as COM files, will start at the beginning of the directory. Cause Hardware problems such as keyboard keys not working, printer issues, modem issues etc. Disable ports such as LPT or COM ports. Caused keyboard keys to be remapped. Alter the system time / date. Cause system to hang or freeze randomly. Cause activity on HDD or FDD randomly. Increase file size. Increase or decrease memory size. Randomly change file or memory size. Extended boot times. Increase disk access times. Cause computer to make strange noises, make music, clicking noises or beeps. Display pictures randomly. Different and/or undocumented types of error messages.

Virus

18

A software program first written Rich Skrenta in 1982 who was a 15-year old high school student. Known as The Elk Cloner this virus spread to other computers by monitoring the floppy drive and copying itself to any floppy diskette that was inserted into the computer. Once a floppy diskette became infected it would infect all other computers that disk was inserted into, each computer that was infected would then infect every floppy diskette inserted into it. A computer that was infected would also display a short poem on every 50th boot. Fred Cohen in 1983 later coined the term virus in a 1984 research paper as "a computer program that can affect other computer programs by modifying them in such a way as to include a (possibly evolved) copy of itself." Today a computer virus is a software program, script, or macro that has been designed to infect, destroy, modify, or cause other problems with a computer or software programs. Users can protect themselves and remove any viruses on the computer by installing an antivirus protection program, which is designed to detect, protect, and clean any computer viruses. Worm1.

First developed by John Shoch and Jon Hupp at Xerox PARC in 1978, a worm is a destructive software program containing code capable of gaining access to computers or networks, and once within the computer or network, causes that computer or network harm by deleting, modifying, distributing, or otherwise manipulating the data.

2.

Short for Write Once Read Many, WORM is a type of CD that can be written to and then read from thereafter. See CD-R for additional information.

What are the current available antivirus programs? Below is a complete list, in alphabetical order, of companies who provide antivirus programs and the platforms they provide protection for. Clicking on the company link will take you to information about that company, including their web page. You can also purchase many of the below virus protection programs through our products page. Company AntiVir AVG ClamWin F-Prot Microsoft Windows Yes Yes Yes Yes Apple Macintosh No No No No19

Linux / Unix Yes No No Yes

Palm WinCE Other No No No No No No No No No No No Yes

McAfee Network Associates Panda Software RAV Sophos Symantec Trend Micro

Yes Yes Yes Yes Yes Yes Yes

Yes Yes No Yes Yes Yes No

Yes Yes Yes Yes Yes Yes No

Yes Yes No No No Yes Yes

Yes Yes No No No No Yes

Yes Yes Yes Yes Yes Yes No

VaccineAnother name for a software utility designed to protect computers from computer viruses. These software programs are more commonly known as a antivirus program. Antivirus program Also known as Antivirus Software, AVS, or just AV; an antivirus program is a type of software that is designed to protect your computer and/or network against computer viruses. If and when a virus is detected, the computer will generally prompt you that a virus has been found, and ask what action should be done such as deleting the virus. Introduction to W I N D O W S Usually the interface between users and computer consists of the screen and keyboard. Users interact with computer by typing DOS commands to do work. Some times DOS command can be confusing and difficult to remember. But with windows, user can run programs, enter the data, move the data/file and perform DOS related tasks by simply using the mouse to point at objects on the screen. FEATURES : (1) (2) (3) (4) (5) (6) Windows supports longer file names rather than limited eight digit letter file name. Windows run more than one programs at a time and move easily between programs whereas DOS does not allow to perform more than one task at a time. Easy to use : Windows can be use easily. Navigating around the computer is easier than DOS In windows users have not remember the different commands like DOS. Windows application is faster than DOS and thereby improve the speed and efficiency. Windows system is more entertaining and interesting. Windows support Digital audio and video, so user can play high quality of digital movies and audio on computer. (7) Windows support the accessing the internet. Graphical user interface (GUI) :

20

The term interface refers to the communication between the user and computer. It is the medium and format through which a user interact with the computer. In GUI the user need not remember a series of commands to perform an action. When the computer is switch on, windows starts automatically. Windows Components : Desktop : The desktop is the first view of the windows operating system after entering the password in the login screen. The desktop contains icons, shortcuts and task bar. Icons : Icons are small bitmap picture files or the picture on the desktop are referred to as an Icons. When icons are clicked programs or applications are launched. These icons arranged in any order in the desktop. They can be drag from one position to another. Start Button : The start button normally appears on the left side of the task bar. All applications are accessible through the start button. Some commands on the start menu have a right facing arrow, which means additional choices are available on a secondary menu. If user place pointer over an item with arrow, another menu appears. Task Bar: It is bar present at the bottom of the screen by default. The position can be sifted according to the users requirement. It provides access to open application. Files : Data stored in the disk in the form of files for the later use. Files are identified by their unique name which allows faster access. Files : the files in the computer are similar to the files that are used in real life. Just as you store document in the file for further use, similarly the data can be store in a computer through file. A file in the computer can not exist without a name. By giving the file a meaningful name you can retrieve the file easily when require. Storage of file : The file needs to be store in a folder, otherwise retrieval become difficult; all the files pertaining to a particular head should be stored in a folder under the name. This organizes the file in the computer. Folders : As in real life the files are stored in a cabinet, similarly in the computer, files can be store in a folder. That is uniquely named corresponding to the file it contained. Files are organized in folders. All related files are clubbed together in a folder. A folder can have many files and also other folders. Renaming files and folders :

21

The name given to the file or folder can be changed. Renaming a file will not create a duplicate copy of the file. A folder can not have duplicate folder or file name. To rename a file or folder select a file or folder and select rename from file menu. Deleting files and folders : The files and folders that are not required can be removed from the hard disk by deleting them. When a file is deleted, it is move to recycle bin. Searching for files or folders : If the location of the files or folder is not traceable, window provides a find feature through which a file or folder can be located. The find facility can be evoked from window explorer or from the start menu. Short cuts : Short cuts provide an easy access method to folders, programs or files. User can place a short cut on the desktop or in a folder. A short cut for the document/ program/ folder can be created. Similarly a program can be started by choosing it from the start menu or by starting it from windows explorer. A short cut can be created to start the program to avoid the large number of steps otherwise required. My Computer : My computer contains or it display all the resources available in the computer. It provides the view of computer contents and manages all files and folders. Ideally it contains 1. 2. 3. all the drives available in the computer the control panel the printer folder

Network Neighborhood : A network is a group of computer connected to each other for sharing the resources like files, folders, printers. It display the group of members computer present in the network. Double click to it gives the browse through other files and folders of other computers on your network. Recycle Bin : It is the storage place for all deleted files. The files which are deleted by users goes to Recycle bin. It acts like a wastebasket that helps to keep all our deleted files and used to restore files. So, the recycle bin is allows deleted files to be recovered by restore command, but files deleted from DOS prompt are not stored in recycle bin. Internet Explorer : It open the internet explorer to surf through the internet. Launching an application : The start button provide the entry point to start any application. The program option in the start button provides access to all the application in the computer. Moving the mouse pointer over programs brings of a sub menu, which contain the name of all the applications and programs group in the computer. Clicking on any of these names with left mouse button start the application.22

An application is currently occupying your desk top and you do not require the application temporarily, click minimize button it will be minimize on the task bar. When you want to start the another application, normally you close the current application. Click on the close button. To maximize an application click on maximize button (Please see the above figure). To scroll the screen click on scroll bar. Using the Start Menu : All the software programs and utilities on your computer are accessed via Windows' start menu. You display the Start menu by using your mouse to click the Start button, located in the lower-left corner of your screen. As you can see in Figure, the Windows XP Start menu consists of two columns of icons. Your most frequently used programs are listed in the left column, basic Windows utilities and folders are listed in the write column. To open a specific program or folder, just click the icon. To view the rest of your programs, click the All Programs arrow. This displays a new menu called the programs menu. From here you can access various programs, sorted by type or manufacture. (When more programs are contained within a master folder, you'll see an arrow to the right of the title, click this arrow to display additional choices.) Lunching a Program Now that you know how to work the Start menu, it's easy to start any particular software program. All you have to do is follow these steps : 1. Click the Start button to display the Start menu. 2. If the program is displayed on the Start menu, click the program's icon. 3. If the program isn't visible on the main Start menu, click the All Programs buttons, find the program's icon , and than click it. Switching between program : After you've launched a few programs, it's easy to switch between one program and another. To switch to another program (and send all other open programs to the background) you can do one of the following: * * Click the application's button in the taskbar Click any visible part of the application's window-including its title bar. window you want is selected. (This cycles through all open windows.) When you're at the window you want , release the Alt key. If you have multiple windows open at the same time, you can determine which is currently the active window by its title bar. The title bat for the active program is23

To switch between applications. * Hold down the Alt key and than press the Tab key repeatedly until the application

brighter, and the title bar text is bright white. An inactive title bar is more dull, with offwhite text. If you have overlapping windows on your desktop , the window on top is always the active one. The active application's Taskbar button looks like it's pressed in. Shutting Down Windows- and Your Computer Windows starts automatically every time you turn on your computer. although you will see lines of text flashing onscreen during the initial startup, windows loads automatically and goes on to display the windows desktop. Do not turn off your computer without shutting down Windows. You could lose data and settings that are temporarily stored in your system's memory. To shut down Windows and turn off your PC, follow these steps : 1. Click the Start button on display the Start menu. 2. Click the Turn off Computer button. 3. When the Turn off Computer dialog box appears, click the Turn Off button. 4. Manually turn off your monitor, printer and other peripherals.

24

WIDOWS ALONG WITH MOUSE What is Mouse ? A Mouse is a hand held device that controls the movement of a pointer on your screen. It can be use to perform various task on your computer. As move the mouse on a pad the mouse pointer moves on the screen to perform different action on the abject. Position the pointer over an object then press the mouse button. For Example : (1) A Double Click :- To open & work in files. (2) Click and drag :- To move files click and drag object means pick up the object by pressing pick up the object by pressing & holding down the left mouse button and droping it on desire position. (3) Click to select files. CLICK ACTION : Click, press & releas the left mouse button ones. (1) Double Click : quickly press & releas the left mouse button twise. (2) Right Click : press & release the right mouse button ones. A sort cut menu display. Introduction : Once windows is started, you will first see the window screen, where password for using the net work service has to be intered on intering the correct password, the user will be able to use network service. If you click on cancel batton you will still be able to work, with windows but you will not be able to use net work services. WINDOWS COMPONENT :- Each time when opens a programme or an application, the work area is defiend within a windows. Window is moveble, resizable and many components of windows are : (1) Title bar - It is located at the top of the window structure. Minimize : Maximize/Restore : Close button :These button are located at the top right corner of the title bar.

25

Close button (cross button) :- It close the windows or end an applicaton. Maximize button (square button) :- It maximise the windows. button) :- If window is maximise restore button

Restore button (Double square gives its original size.

Minimize button : It will put the open window on the taskbar. Menu bar :- The menu bar is located just below the title bar which takes name of pulldown menu like File, Edit, View, Help etc.. Tool Bar :- It has command button with pictures. Scroll Bar :- There are two types of scroll bar : (1) Horizontal (2) Vertical . Use the scroll bar to view different parts of the window document screen. Status Bar :- Window display certain information like page no, how much the hard disk space is left or what objects are currently selected in ststus bar. How to create folder and Short cuts ? Folder : A folder is a organization of many files and folders. All related files are clubbed together in a folder. Each folder has its own icon name. Steps for creating folder: 1. 2. 3. mouse. 4. 5. once. Place the pointer on the blank space of the desktop by using mouse. Click right button of mouse once. A new menu displays on the desktop. Select the New option from this menu by clicking left button of Then another new submenu displays on the desktop. Select the Folder option from this sub menu and press left button

6. So, new folder will create on the desktop and give the suitable name to this folder. SHORT CUTS : Short cuts provide an easy access method to folders, programs or files. User can place a shortcut on the on the desktop or in a folder. Steps for creating Short Cuts: 1. Place the pointer on the blank space of the desktop by using mouse. 2. Click right button key of mouse once. A new menu displays on the desktop. 3. mouse. 4. 5. once. Select the New option from this menu by clicking left button of Then another new submenu displays on the desktop. Select the Shortcut option from this sub menu and press left button

26

6. So, another page (dialog box) display in which press the Brows option by clicking left mouse key. 7. Then select require folder or program from the program files. Then press next option and finally finish option by mouse. At last a new short cut key display on the desktop with given name.

MICROSOFT WORDWHAT IS A WORD PROCESSOR ? A Word Processor is a program that lets you enter, edit, format, store, and print text. It can be used to type letters, reports, etc. and to do other work you were doing using a type writer. SOME FEATURES OF MS-WORD Buttons on the toolbars to make complex tasks easy A number of ways to view a document Easy editing and formatting Finding and replacing Changing case Spell checking, Thesaurus and Grammar Character formatting Changing margins and paper size Page numbering Inserting special Characters, objects, pictures and drawings Creation of Tables Auto text and Auto correct Creation of Equations using mathematical symbols. Mail merge WHAT YOU SHOULD KNOW ? Simple Operation of Windows Use of pull-down menus Use of dialogue boxes Use of buttons on Tool Bars Using mouse Single Click Double Click Dragging STARTING MS-WORD Do any one of the following : Click the MS-WORD Icon on MSOffice Tool Bar Click Start Move the pointer to Programs Move the pointer to MSOffice27

Move the pointer to MSWord Click once If Tip of the day dialogue box is displayed, click OK. Using word commands A commands is an instruction that tells word to do something. You can quickly choose the most common word commands by using the mouse to click buttons on toolbars. In word, commands are also grouped on menus. Some commands carry out an action immediately; others display a dialog box so that you can select options. To choose a command from a toolbar click the appropriate button on the toolbar. To interrupt a command, Press ESC. MS-WORD SCREEN Microsoft Word Screen consists of the following : Title Bar Displays the title(name) of the document. The default name is DOC1.DOC. However you can change it.It is located across the top of the screen below the Title Bar. Menus are accessed by clicking a menu name with the mouse. Once a menu is pulled down, you can select one of the selections with the mouse. Includes buttons to perform the most frequently used editing Standard Tool Bar operations.

Menu Bar

Formatting Tool BarTyping Area Scroll Bar Status Bar This is the blank part of the screen on which you enter your document. The scroll bars are used to move your display horizontally and vertically. The status bar is located at the bottom of the screen. Here, you can view the page and section number and the position of the pointer on the screen. Includes buttons to change font, font size, type style , alignment, etc..

Creating a new document When you start word, a new blank document named document1 opens. To begin working on it, just start typing. A blinking vertical bar called the insertion point indicates where text will appear when you reach the right margin. Word automatically warps text to the next line. You press enter only when you want to start a new paragraph. Most of your document will contain more text than you can see at one time. To view parts of a document that you cannot see, use the mouse or the keyboard to scroll through the document.

28

Saving document Click save button on standard tool bar to save the document. Word displays save as dialog box for saving file contest for the first time only. You specify the name, and location of the active document. The name of the document must consist of at most 8 charters followed by 3 character extension. Dos extension by default. For your convenience, you give a meaningful name to your document reflection in the contest of the document. Quitting word To quit word do one of the following : 1. Click the close button on the top right corner of the word window. 2. From the file menu choose exit. Opening an existing documents When you open a document, word copies it from the disk and displays it in a document window. To open an existing document, click the open button on the standard toolbar or use the open command in the file menu. The open dialogue box appears on the screen. In the file name box, click the name of the you want to open and then click OK. Make the desired changes in the document, if required and save it. In word you can open several documents at a time. Printing a document On the standard toolbar, click the print button word prints one copy of the document. Setting printing options 1. From the file menu, choose print 2. Do one of the following : Do this To print Only the page containing the insertion point The current selection A range of contiguous pager Noncontiguous pages Under page range, select the current page option button. Under page range, selection option button. Type a range with a hyphen between the page numbers. In the pages box, under page range type the page number separated by commas. For example to print pages1 and 6 type 1,6 In the print box select odd pages or Even pages. In the print what box select document and under page range select the all option button.

Only odd or even pages An entire document

29

Multiple copies of the entire document

In the copies box type or select a number of copies. To sort the pages by page number, select the collate copies check box

3. Choose the OK button. Selecting text and graphics by using the mouse To select Any item or amount of text A word A graphic A line of text Multiple lines of text A sentence A paragraph paragraph, Multiple paragraphs An entire document Do this Drag over the text you want to select Double click the word. Click the graphic Click in the selection bar to the left of the line. Drag in the selection bar to the left of the line. Double-click anywhere in the sentence. Double-click in the selection bar next to the or triple-click anywhere in the paragraph. Double-click and drag in the selection bar. Triple-click in the selection bar.

Canceling a selection You can cancel a selection by using either the keyboard or the mouse. Using the mouse click anywhere outside the selection in the document window. Using the keyboard press any arrow key. Deleting text and graphics You can delete text and graphics in two ways : you can remove them permanently or insert them in another location. If you accidentally delete text, you can restore it with th undo button. To delete text and/or graphics, select it using the mouse and click cut button on the standard tool bar. To restore deleted text and graphics To restore deleted text and graphics immediately after deleting them, click the undo button on the standard toolbar. To undo multiple actions, click the down arrow next to the undo button on the standard toolbar, and then drag to select the actions you want to undo. If you undo an action you decide was correct after all, you can reverse the undo action by clicking the redo button.

30

Replacing a selection with new text 1. Select the text you want to replace. 2. Type the replacement text. The text you type entire selection. Changing the capitalization of text You can quickly change the capitalization of text without retyping making selected text all lowercase or all uppercase letters, capitalizing only the first letter of each word, capitalizing the first word of a selection, or switching existing uppercase letters to lowercase letters or vice versa. 1. Select the text you want to change. 2. From the format menu choose change case. 3. Select the option you want, and then choose the ok button. Moving or copying text and graphics by using the standard toolbar Select the and graphics you want to move or copy. To move the selection, click the cut button on the standard toolbar. To copy the selection click the copy button on the standard toolbar. Word places the text on the clipboard. Position the insertion point in the new location. On the standard toolbar click the paste button. Inserting symbols Position the insertion point where you want to insert the symbol. From the insert menu choose symbol. Double click the symbol character you want word inserts the character in the text that precedes the inserting point. When you finish inserting symbol choose the close button. Finding and replacing text and formatting 1. Form the edit menu choose replace. 2. In the find what box type the text. 3. In the replace with box type the text. 4. Select the other options your want to use to control the search. 5. Do one the following: 6. To close the dialog box choose the cancel or close button. ToReplace the text or formatting and find the next occurrence Change all occurrences without confirmation Leave the text or formatting unchanged search for the next occurrenceChoose

The replace button

The replace all button

7. To close the dialog box choose or close button. FORMATTING TEXT To apply or remove character formats31

Select the text. To change the font or font size, select a font name or font size in the font box or the font size box and then press Enter. To add or remove bold, italic or underline format click the bold italic or underline button.

To change text color Select the text you want to change. From the format menu, choose font. In the color box, select the color you want. Word comes with 16 predefined colors. Choose the OK button. Centering or aligning text Word is preset to align text flush life with the life margin, producing a ragged right edge. However, you have the option of centering text, aligning it along the right margin or expanding the spaces in each line to align text at both the life and right margins. The alignment you select affects all text in the selected paragraphs. To center or align text Select the paragraphs you want to center or align. On the formatting toolbar click the button for the alignment you want. Changing line spacing Word is preset to use single line spacing. When you change line spacing it affects all lines of text in the selected paragraphs or the paragraph that contains the insertion point. To change line spacing Select the paragraphs whose line spacing you want to change. From the format menu, choose paragraph. In the line spacing box under spacing, select the type of line spacing you want. Choose the OK button Inserting page numbers From the insert menu choose page numbers. Select a location in the position box. Select a location in the alignment box. Choose the OK button. TABLES A table consists of rows and columns of cells that you can fill with text. Within each cell, text wraps just as it dose between the margins of a document. The cell expands vertically to fit the amount of text you type. Creating a table 1. Position the insertion point where you want to create a table. 2. On the menu bar, click table. 3. Click insert table on the pull down menu. 4. Type the number of rows and columns in the dialogue box. 5. Click OK. 6. The gridlines that you see help you enter data into the cells but they dont print.32

7. You can move around the cells using the mouse. Selecting rows and columns 1. For selecting a row click the row selection bar. 2. For selecting a column click just above the top of it. 3. For selecting a cell click the cell selection bar. 4. For selecting a group of cell rows or columns, drag across cell rows or columns. 5. For canceling the selection, click any where on the table. Adding rows to a table Select the row or below where you want to insert a new row or rows. From the table menu, choose insert rows. Word inserts a row above the rows you selected. Adding columns to a table Select a column to the right of where you want to insert a new column or columns. From the table menu choose insert columns. Word inserts a column to the life of selected column or columns. You can have a maximum of 31 columns in a table. Deleting cells, rows, or columns To delete cells in a table, select the cells you want to delete and press Del key. To delete rows or columns in a table, select the rows or columns you want to delete and press Del key. You can also delete rows or columns by using the cut button on the standard toolbar. Changing column width in a table Position the mouse pointer over the column boundary. When the mouse pointer changes, double-click the column boundary to automatically resize the column Or drag the column boundary to the right or life. Merging or splitting cells To merge cells in the same row of a table, select the cells you want to merge. You can select in the same row of cells, but cells will only be merged horizontally. From the Table menu, choose Merge Cells. To split cells, select the cells you want to split. From the Table menu, choose Split Cells. From the Table menu of columns you want to split cells. Type the number of columns you want to split each cell into, and then click OK button. Sorting formation 1. Select the rows you want to sort. 2. From the Table menu, choose Sort. 3. Under Sort By, select a column number, field number, paragraphs, or name. 4. Select the Ascending or Descending option button. 5. Choose the OK button.

33

Performing calculation in a table To sum a row or column of number position the insertion point in the cell where you want the sum to appear. From the table menu choose formula. Word analyzes the table proposes the appropriate formula in the formula in the formula box. Choose the ok button. EQUATIONS You can build complex equation by picking symbol from a toolbar and typing variable and numbers. As you build an equation editor automatically adjusts font size spacing and formatting. Easy-To-use toolbar symbol and templates The top row of the equation editor toolbar has button for inserting more than 150 mathematical symbols, many of which are not available in the standard symbol font. The bottom row of the equation editor toolbar has buttons for inserting about 120 templates or frameworks that contain such symbol as fraction radicals summation integrals products matrices and various fences Creating an equation Click the Equation Editor button on the tool bar or Select Microsoft Equation 2.0 from Object, Insert Menu Choose a template from the bottom row of the toolbar and fill in the slots. Choose symbols from the top row of the toolbar. Type the text you want. When you have built the equation, click anywhere outside the Equation Editor window to return to your document. Editing an equation Double-click the equation. Select Microsoft Editor toolbar displays and its menu bar temporarily replaces the application menu bar. Make the changes you want. When you have finished editing, click anywhere outside the Equation Editor object.

MS-EXCEL Electronic Sheet- working with work34

Spread Sheet: A Spreadsheet is application software, which is divided in to rows and column. It is mostly use for calculation purpose like preparing salary sheet balance sheet It provide for automatic calculation which menus if any data is change the result automatically changes It also you to perform detail analysis or data spread sheets are first and accurate roots for performing complete data analysis. The spreadsheet also allows up to represent the data with the help of a graph. Some of the popular spreadsheets packages are lotus123, FoxPro, excel etc. MS excel is window base spread sheet It can be use for a verity applications. Features of Excel :(1) Automatic number formatting. Automatic summation and calculation. (2) Automatic work sheet formatting (4) Variety of Built in spell checking (8) "What if " analysis database management. Workbooks and worksheets: When you launch Excel, the Excel application window opens with a new Excel workbook. A workbook is a multi-page Excel document. Each page in the workbook is called a worksheet, and the active worksheet is displayed in the document window. At the left end of the horizontal scroll bar are sheet tabs and navigation button. Use the sheet tabs to move to another worksheet and the navigation buttons to scroll the sheet tabs. Work Sheet:A work sheet is large planning form made up of row, columns and cells separated by a grid lines. The horizontal section is called row. There are rows numbered from 1 to 65356 and The vertical division is called column. Columns named as from A to Z double AA to AZ. the last column is IV. Total columns are 256. The intersection of a column and a row is called a cell a dark rectangle dialog box is seen on the screen which show as the active cell on the dark sheet the active is the cell in which we can started typing a data in excel in initials 3 work sheet are available additional work sheet can be added as necessary sheet to sheets 3 display on the action screen each work sheet is independent all the others although the values in the different sheet can be combined. Work Book (3) Function wizard. (5) Short cut menus

(6) Drag and drop work sheet rearrangement (7) Chart

35

In MS-Excel the file in which for and store you data is called a work book each work book consists of verticals sheets the sheet tap at the button of the screen allows us to shift but when the sheet in work book, one work book can consist of any number of excel sheets. Starting Excel The start excel steps are (1) Click on the start button. (2) Select program action from the start up menu. (3) Select Microsoft excel from the another menu. Working With In Work Sheet Data entering to a cell the steps to the data in to a cell are (1) (2) (3) Select the cell by clipping on it. Type in the value. Press enter key.

Type Of Data : Three types of data can be entered in a worksheet numbers, formulas, and text Numbers are values you may want to use in calculations, including dates. Dates are often used in calculations to determine, for example, how many days to charge for an overdue video or how many months of interest you have earned on a deposit. Formulas are calculations. Text is any entry that isnt a number or a formula. To enter data in a cell, first activate the cell, then begin typing the data. As soon as you begin entering characters from the keyboard, three things happen: an insertion point appears in the cell, the text you are entering appears in the cell and the formula bar, and the formula bar buttons are activated. You can enter and types data in a work sheet. (1) (2) (3) A Numeric value : constants value does not change unless you select the cell and edit the value. A text : Title or name, address etc. (Non numeric items) A Formula :- It is a simple soft values names formula a longs being with and excel size numbers some numbers and some characters like +,-,),(,$,%,&,etc. (4) Date : Selection Techniques To select Cells Range of cells Click the cell. Click the cell of the range to the require cell.36

Do this

All cells An entire row An entire column Selecting Multiple cells:

Click the select all button from edit menu or Ctrl + A Click on the row heading. Click on the column heading.

In Excel, at least one cell is always selected: the active cell. A group of cells is called a range. To select a range, move to the first cell in the range (check to be sure the mouse pointer is the large cross used for selecting), hold down the mouse button, and drag to the last cell you want to select before releasing the mouse button. To select all the cells in a column or row or column headers to select them , be sure that your mouse pointer looks like the fat selection cross as you do this, not a thinner black cross. To select the entire worksheet, click the Select All button, the gray rectangle at the upper left corner of the worksheet above the row headings. If the cells, columns, or rows you want to select are noncontiguous (not next to each other), select one of the ranges you want to select , then hold the Ctrl key on the keyboard down while selecting the others. Inserting and Deleting Rows and columns: To insert a column between the current columns A and B, begin by selecting column B Right-click and select Insert from the shortcut menu or choose Insert Columns from the menu bar to insert a column. To insert multiple columns simultaneously, select more than one column before inserting. For example, you can insert three columns by first selecting B,C, and D. You can inset rows in the same fashion. Edit part of the information Within the cell steps to edit the value are:(1) Select the cell whose value need to the edited. (2) Double click the cell to edit it. (3) If you need through replace entire value type in the new value with out double clicking the cell while editing you want to retain the previous value click on the cancel current button on the formula bar. The steps to clear cell content are :(1) Select the cell. (2) Select clear content option from short cut menu. After natively you can select the clear option from the edit menu from the sub menu select content option.

37

Copying & Moving Cell You can change the location of cell on a work sheet by copying or moving cell to a different part of the same work sheet within workbook or to another application. There are two ways to copy and move cell (1) By using cut, copy and pest. (2) By dragging with mouse. (1) Cut, Copy and Pest method: (i) Select the cell you want to copy and choose the copy command from the edit menu. the copy area is marked with moving a border. (ii) Select the destination cell now Choose the pest command from edit menu. The moving border indicates you to cancel the border pest the escape key. (2) Dragging method :Position the mouse pointer over the border of selection hold down control key and drag the folder in a new location and than release the mouse button and than control key and contains are copy to their new location. Moving :(1) Cut, Copy and Pest Method :(i) Select the cell you want to Move and choose the Cut command from the edit menu. The Cut area is marked with moving a border. (ii) Select the destination cell Choose the pest command from edit menu. Dragging method :Position the mouse pointer over the border of selection hold down control key and drag the border in a new location and than release the mouse button and than control key and contains are move to their new location. Inserting and deleting cells, rows and columns. You can enter blank cell row and column any where on work sheet you can also delete cells entire rows and column from work sheet.

Deleting cells, Rows and Columns: In excel you can insert or delete cell, rows and columns with out affecting surrounding rows and columns the step to delete a cell or group of cell are: (1) Select the cell or range of cell that you want to delete. (2) Select the delete option from the edit menu. The delete dialog box is displayed. In delete dialog box select the direction you want to surrounding

38

cell to move you can also select the entire row or column option to delete row or columns. (3) Select the appropriate option and click on the ok button to delete the cell. Inserting Cells Rows and Columns :The steps to insert cells rows and columns are (1) Select the cells rows and column where you need to insert new cell column or rows. (2) Select the insert option from the edit menu. Formulas :Formula are powerful feature is spread sheet formula establishment relationship between two or more cells you can use formula for performing calculation involving addition subtraction multiplication and division formula are also the key to performing complex scientific and statistical operation formulas are store in cell like data however they display the result of the calculation in the cell rather then data. Entering Formulas :Formulas in excel always begin with equal sign and can include numeric and text value constant operate and cell retunes by combined this components you can calculate the result you want from data store in double sheet you can enter formula in cells in the same way you enter normal data values. (1) Double click on the cell. (2) Type the equal sign. (3) Type in the formula including cell reference and operation like + or -, / or *. (4) Press the enter key or click on the enter cursor value button e.g. To calculate the total of the value in the cell A1 to A5 and store the result in A6 perform the following steps (i)(ii)

Double click on the cell. Enter the formula like equal to =A1 + A2 + ...... + A5 press enter key the total in the value of the cell from A1 to A5 is displayed in A6.

Function: There are readymade function in excel, you can select it by using pest function for total use auto sum button and give range of data. Saving a Worksheet: To save active work sheet select the save command from file menu or click the save button from standard tool bar. If you haven't save the work sheet previously the save as dialog box appear so that you can type name for a work sheet you can select the drive directory or a folder where you want to save your work sheet.39

You can save the workbook in another file format such as lotus 123 just choose a format in the save file as type box of save as dialog box. Printing a Worksheet :The steps to print a work sheet (1) Select the print option ion the file menu. the print dialog box is displayed. (2) Select the printing option from print dialog box. (3) Click on ok button. The work is printed on selected printer. If data in as work sheet does not fit in to a single sheet on paper excel prints on multiple pages you can also print the entire work book option in the dialog box. CHART: A Chart provide a visual representation of the value contain on work sheet chart can help in decision making and for comparison you create several kind of chart in such as bar, column, line, pai etc. CREATING CHARTS The steps to create a chart (1) (2) (3) (4) Select the cells that you want to contain the data that you want to appear in tool bar a chart. Click on chart wizard button from the standard tool bar it will display dialog box of chart type. Select the main chart type and select the chart sub type on the right hand side. Click on next when you have select the chart type. It will display dialog box of chart either in column or row wise it will take a range which we have selected as me range of chart series will in the columns if the field of the data list are of the different column and series will be in rows if the field of the data list are in the different rows. (5) Click on next when you give the chart source data it will display the title table and give and various titles like chart X axis and Y axis titles click on the axis option if you want to give / remove the value shows on X and Y axis the show on X and Y axis. The grid line option table will allow you to give / remove the grid lines from the chart. The legend allow to give or remove legend to the chart can be place bellow above on left right of the chart depending on the option you have selected. Data Table :If the option is on the data base on which the chart is down will also displayed along with chart.40

Click on next :- Choosing option It will display the dialog box chart location you can select weather you want the chart to appear different sheet or as object on the already existing sheet the existing sheet may can be selected from drop from list. Once this is done click on finish the chart will appear when a work you have selected the option Changing the Chart Type :You can change the type of chart of choose different sub type of the save type. The stapes to change the chart type (1) (2) (3) (4) (5) Select the chart. Select the chart option from menu bar. Select the chart type option from the format mark the chart type dialog box is display. Select the main chart type and select the chart sub type. Click on ok button the chart type is change according to the selection

WWW- World Wide Web : The Internet application that is currently drawing the most attension is the World Wide Web (WWW), WWW is a series of servers that are interconnected through hypertext. Hyertext is a method of presenting information in which cretain text is highlighted that, when selected , displays more information on the particular topic. These highlighted items are called hyperlinks and allow the users to navigate from one document to another that may be located on different servers. The user can use the browser software like, Internet Explore, Mosaic or Netscape Navigator to navigate the Web. A browser is a software that helps the user to navigate the WWW. The web is a graphic medium with most Web pages having some amount of images. The term home page commonly refers to the index page of any organization or information source. The home

41

page can have links that take the user futher levels of information within the same topic, or there can be links to other home pages. Common Terminologies : Some of the most commonly-used terminologies related to WWW are : * Browser : - is client software that allows the user or display and interact with a hypertext document. * Web server : - is a place where pages reside. It is a program that responds to requestes from Web browsers to retrive resources. It is also used to refer to the computer that runs the server programs. Some popular Web servers available are Internet Information Server (IIS) from Microsoft, Fast Track from Netscape and Intra Netware from Novell. Home Page : - is the first hypertext document displayes when the user follow a link to the Wev server. Hypertext Markup Language (HTML) : - is the encoding scheme used to creat a web document. Hypertext Transfer Protocol (HTTP) : - is a protocol used on the Web to transfer hypertext documents. A protocol is a set of rules that the computers use to communicate logically. Uniform Resource Locater (URL) : - is a Web addressing scheme that spells out the exact location os an Internet resource. When the user liicks on a link, the browser reads the like to the document. The information about the link is provided to the browser by the URL. Any link from one gocument to another is always implemented by using URL. Web Browsers : The browser is the program which is necessary for surfing the Internet. Following are some examples of web browsers, Internet Explorer 6 is the dominating browser, XP is the most popular operting sysytem, and most users are using a disply with 800 x 600 pixels or more, with a color depth of at least 65K colors. 1. Internet Explore : Interet Explore (IE) by Microsoft is the most popular Internet browser today. IE was introduced in 1995 and passed Netscape in popularity in 1998. 2. Netscape : Netscape was the first commerical Internet browser. It was introduced in 1994. Netscape has gradully lost its popularity to Internet Explore. 3. Mozilla :

42

The Mozilla Project has grown from the ashes of Netscape. Browsers based on Mozilla code is the second largest browser family on the Internet today, representing about 20% of the Internet community. 4. Firefox : Firefox is a new browser from Mozilla. The browser is a very promising and expected to gain a high market share. 5. Opera Opera is a Norwegian Internet browser. It is known to be fast and small, standards compliant and available for many operating systems. OPera is the perferred browsers for a number of small devices like mobile phones and hand-held computers.

43