D.G Subramanya BE (CS)

LecturerSahyadri Arts and Commerce CollegeShimoga

Computer Application in Business

Definition: Computer is an electronic device used for information processing. It accepts data and instructions, stores in its memory, processes and gives the results to the user. The term computer derived from the Latin word compute, which means to calculate or manipulate. Therefore computer is a calculating machine.

Characteristics of Computer: High speed: A computer is a fast information-processing device. It carries out all sorts of

computations within a fraction of seconds. The speed of computer is measure in millions of instruction per seconds.

Accuracy: Computers operate at a very high degree of accuracy. It gives accurate results for correct input data. Here accuracy means the correctness of processed data.

Reliability: It gives consistent result, even though it is running on electrical connections and electronic circuits.

Versatility: It is used for different fields of human endeavor ranging from business, education, technology, engineering, law, commerce, agriculture, medicine, sports.etc it can perform different types of tasks provided such tasks can be stated in logical way for the computer to execute.

Memory: Secondary storage devices are the key for the data storage. They store the data for which the user wants to retrieve these data for future use. The examples for various secondary devices are Floppy disk, Optical disks.

Diligence: Computers never get tired as the humans do. If there are surplus amount of executions to be made then each and every execution will be executed at the same time. They can perform their assigned task without taking any refreshment. (It does not feel tired. It can be used for number of days without stop.)

Automation: Computer can calculate the results automatically once the formula given. It may execute the process without any intervention of user once they are assigned to a work.

Programmability: The computer can be programmed to do all forms of activities of man. Limitation: A computer cannot think and find the results its own as a human being. It cannot

make the decision of its own. It needs a guidance to enhance the process.

1

Applications of Computers in various fields

Science: One of the most important advantages of computers is in the field of science for research and development. The satellites, the telescopes and almost all the research tools make use of computers in some or the other way. The huge calculations required for space science, storage of all the gathered information are some of the computer uses in science and technology.

Medical: The important use of computers in the medical field is for research and development. The high end machines used for diagnosis and cure of many diseases. Even many surgical procedures need the help of computers. Web conferencing helps doctors treat people remotely. 

Education: Computer uses in the field of education are infinite. The Internet is a huge source of information. There are online universities that deliver online degrees and distance learning is spreading far and wide. Many schools and colleges have started making use of audio-visual ways of imparting knowledge.

Banking: The banking sector has improved with the help of computers. Most of the banking operations can be done online, known as Internet banking. We can withdraw money from ATMs and deposit money in any branch

Crime Investigation: High end computer devices have ensured that justice is more effective. CCTV cameras and other computer operated security systems have reduced the amount of crime.

Entertainment: The field of entertainment has been revolutionized by computers. Animation, graphic image manipulation etc has made the entertainment experience hundred times better. Movie making, editing, music composition etc everything needs computers. 

Industry: Computers are finding their greatest use in factories and industries of all kinds. They have taken risky jobs like welding to highly complex jobs such as process control. Moreover, quality control tests and the manufacturing of products, which require a lot of refinement, are done with the help of computers. Not only this, Thermal Power Plants, Oil refineries and chemical industries fully depend on computerized control systems.

Transaction: Transaction processes in important for accurate accounting and for immediate availability on line information. Indian railways have introduced computerized ticket reservation. The computer stores all necessary details such as train number, distance, number of seats available on each train, fare etc. Computer are also used for reservation tickets for airlines and transportation.

Remote sensing applications: Super computers in satellites are used for remote sensing to locate crude oil and other natural resources inside rocks, sea and desert inside and also weather forecasting applications, Military application, Agriculture application

2

Generations of Computer

Each generation of computer is characterized by a major technological development that fundamentally changed the way computers operate, resulting in increasingly smaller, cheaper, more powerful and more efficient and reliable devices.

First Generation Computer (1946-56)These are developed during 1946-56, and were built with Vacuum tubes for circuitry

and magnetic drums for memory. They were very expensive to operate and in addition to using more electricity and generated a lot of heat.

First generation computers used on machine language they could solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts. The UNIVAC (Universal Accounting Computer) and ENIAC (Electronic Numerical Integrator and Calculator) are examples of first-generation computing devices.Advantages

These computers were fastest of their time They were programmed using machine language

Disadvantages Larger in size Consumed large amount of energy More hear generated and air conditioning was required Non portable Very slow in speed It was difficult to programming Limited commercial use

Second Generation computer (1956-1963) TransistorsTransistors replaced vacuum tubes in the second generation of computers. The transistor

was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than first generation. Transistor still generated heat that subjected the computer to damage. Punched cards for input and printouts for output.

Second generation computers moved from machine language to assembly language. High-level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology. The first computers of this generation were developed for the atomic energy industry.Advantages:

Smaller in size Less heat generated Consume low power Fast in speed Used for commercial purpose Assembly language was introduced

Disadvantages: Air conditioning required Commercial production was difficult and these were very costly Only used for special purpose

Third Generation computer (1964-1971) Integrated Circuits

3

The development of the Integrated Circuit was the main components of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which increased the speed and efficiency of computers.

This generation computers use keyboards, mouse and monitors and interfaced with an operating system, which allowed the device to run many different applications. The concept of operating system, multi-programming, parallel processing were introduced. They are used in weather forecasting, airline reservations and banking services. Advantages:

Smaller in size Less heat generated Consume low power More reliable Hardware failure was very low Easy to operate Easily portable Magnetic disk used for external storage More storage capacity Very fast in computational power Widely Used for commercial purpose High level language was introduced

Disadvantages: Air conditioning required Highly sophisticated technology required for the manufacture of chips

Fourth Generation (1971-80) MicroprocessorsThe Microprocessor used in the fourth generation of computers, as thousands of

integrated circuits were built onto a single silicon chip. It reduced the size and price of the computers at the same time increasing power, efficiency and reliability. The Intel 4004 chip, developed in 1971, located all the components of a computer.

(Very Large Scale (VLSI) and Ultra Large scale(ULSI) ensured that millions of components could be fit into a small chip.)

In 1981 IBM introduced its first computer for the home user. As these small computers became more powerful, they could be linked together to form networks and development of the Internet. This generation also development of GUIs, the mouse and keyboard.

Advantages: Smaller in size Air conditioning is not compulsory Consume low power More reliable Hardware failure is negligible Easy to operate Easily portable More storage capacity Very high processing speed Very large internal and external storage capacity Widely Used for commercial purpose Used advanced input and output devices such optical reader, laser printers,

CD-ROM/DVD drives etc

4

Disadvantages: Highly sophisticated technology required for the manufacture of Microprocessor chips.

Fifth Generation (1980-since) (Present and Beyond) Artificial IntelligenceThese computers will be under Artificial Intelligence (AI). They will be able to take

commands in a audio visual way and carry out instructions. Parallel Processing is coming and showing the possibility that the power of many CPU's can be used side by side, and computers will be more powerful.

Supercomputers are fastest type of computer, very expensive and are employed for specialized applications that require immense (huge) amounts of mathematical calculations. For example, weather forecasting requires a supercomputer. Other uses of supercomputers include animated graphics, fluid dynamic calculations, nuclear energy research, and petroleum exploration (searching).

Features: Having their own thinking power Making decisions themselves Having capability of learning Large capacity of internal storage Very high processing speed Capabilities of parallel processing

5

CPU

Arithmetic and Logic Unit

Control Unit

Memory unit

Main memory

Secondary memory

Input Device

Output DeviceData and

Instruction

Block diagram of Digital ComputerSystem Unit

Input Device: Input device is an external device that is connected to the CPU. It is used to transfer data and instructions for solving the problem. The control unit sends signal to this unit to receive data and instructions from the user and communicated to the CPU. The most commonly used input devices are keyboard, mouse, joystick, disks, light pen, microphone etc.Output Device: It is used to display the result after execution of a program. The control unit sends the signal to this unit to be ready to accept processed data from memory and display it. The most commonly used display unit is monitor, printer, plotter, disks, voice output (speaker) etc.System Unit: Once the data and instructions are received from input unit they are stored and processed in the system unit. The system unit further consists of two sub units. They are Central Processing Unit (CPU) and Memory Unit (MU).Central Processing Unit: It is generally called CPU. Once the data and instructions are received from the input unit, they are to be processed in this unit. So, it can be considered as heart and brain of the computer system. Further, the CPU consists of two important functional units. They are Control unit and Arithmetic logic unit.Control Unit: It is an important unit in a computer. It controls and coordinates the activities of all the units of a computer system. It sends control and timing signals to various units to coordinate for the specific operation. The following some function performed by the control unit.

Fetching a data and instructions from main memory. Interpreting these instructions. Controlling the transfer of date and instructions to and from main memory. Controlling input and output devices.

Arithmetic and Logic Unit: All calculations are carried out in Arithmetic and logic unit. An ALU consists of electronic circuitry, which performs basic arithmetic operations such as addition, subtraction, multiplication and division. It also consists of logic circuitry, which performs logical operations either true or false. ALU receives signals from the control unit to coordinate for the above operations.Memory Unit: It is a storage device. The memory of computer is measured in terms of bits, bytes and words. Computer memory classified into main memory and secondary memory.

6

Main Memory: This is a temporary memory. This is also referred to as primary memory. It is made up of semiconductor material. It consists of RAM and ROM main memories.Secondary Memory: Secondary memory is a permanent memory it is also called as Auxiliary memory. It can be used for storing system program, application program, assembler, compilers, large data files and other programs. It is made up of magnetic materials. Magnetic tape, magnetic drums and magnetic disk are the secondary storage devices.

Types of Computers

Based on the principles of operation, computers are classified into three types Analog computer, Digital computer and Hybrid computers.

Analog Computer

The word ‘Analog’ means continuously varying in physical quantity, the analog computers accept input data in continuous form and output obtained in the form of graphs or analog signals and it is measured on a scale. The voltage, current, pressure, temperature, speed, sound etc are the values are examples of analog data. These values continuously increase and decrease.

The analog computers have low memory size and used in limited functions. These are very fast in processing but output is not accurate. These are used in industrial units to control various processes and also used in engineering field.

Digital computer

The word ‘Digital’ means numbers. It refers to binary system, which consists of only two digits i.e 0 and 1. Digital data consists of binary data represented by OFF (low) and ON (high) electrical pulses. A digital computer operates by counting numbers or digits and gives output in digital form. Digital computers can give results with more accuracy and at a faster rate.

Since many complex problems in engineering and technology are solved by the application of numerical methods. Hence digital computers used in the field of design, research and data processing.

Hybrid computer

A hybrid computing system is a combination of desirable features of analog and digital computers. It is mostly used for automatic operations of complicated physical processes and machines. Now-a-days analog-to-digital and digital-to-analog converters are used for transforming the data into suitable form.

For example in hospital’s analog devices might measure the patient’s temperature, blood pressure and other vital sign. These measurements which are in analog then converted into numbers and supplied to digital components in the system. Hybrid computers are mainly used for specialized tasks.

7

Classification of computers based on configuration

Based on performance, size, cost and capacity, the digital computers are classified into four types: Micro, Mini, Mainframe and Super computers.

Microcomputer: Microcomputer is at the lowest end of the computer range in terms of speed and storage capacity. These are general-purpose computers. The name microcomputer is due to the use of a microprocessor as its CPU. Microcomputers are often referred to as personal computers (PCs) because they are used by one person at a time. Basically these are 8 bit or 16 bit computers. Now a day, microcomputers of 32 bits or 64 bits are available. Mini Computer: This is designed to support more than one user at a time. It possesses large storage capacity and operates at a higher speed. The mini computer is used in multi-user system in which various users can work at the same time. This type of computer is generally used for processing large volume of data in an organization. They are also used as servers in Local Area Networks (LAN). Mainframes: These types of computers are generally 64-bit microprocessors. They operate at very high speed, have very large storage capacity and can handle the work load of many users. They are generally used in centralised databases, banks and airlines reservations. They are also used as controlling nodes in Wide Area Networks (WAN). Example of mainframes are HP and IBM series. Supercomputer: They are the fastest and more expensive machines. They have high processing speed compared to other computers. They have also multiprocessing technique. One of the ways in which supercomputers are built is by interconnecting hundreds of microprocessors. Supercomputers are mainly being used for weather forecasting, biomedical research, remote sensing, aircraft design and other areas of science and technology. Examples of supercomputers are CRAY and PARAM.

8

CPU

PRINTEROS

MOUSE KEYBOARD

MONITOR

FLOPPY/HARD DISK MODEM APPSOFTWARE

CHAPTER 2COMPUTER HARDWARE AND SOFTWARE

Computer hardware: The physical component of the computer system is called hard ware, which are visible to the user. The user can directly operate these devices. Computer hardware includes input devices, output devices, processing devices and other peripheral devices. e.g.: keyboard, mouse, monitor, printers, scanners, hard disk, floppy drives etc.

Computer Software: A set of programs written to a computer is called software. It is any prepared set of instructions that controls the operations of the computer, which deals with the codes, coded instructions according to which the computer operates. Software generally classified into two types 1). System software 2). Application software

System Software: System software is a set of one or more programs, which are designed to control the operation and extend the processing capability of the computer system. It is acts as intermediatory between hardware and application programs. Ex: Ms-Dos, Unix, Windows, Assembler, Compiler, Interpreter.

Application Software: Application software is a set of one or more programs designed to do a specific task such as processing of student admission, examination result, pay calculation, etc. The most widely used general purpose application packages are EXCEL, WORD, ORACLE, DTP packages and etc.

OPERATING SYSTEMS

An operating system is a master control program that runs the computer and as a scheduler. It controls the flow of signals from the CPU to various parts of the computer. It is the first program loaded (copied) into the computer’s memory after the computer is switched ON.

An operating system is a program designed to run other programs on a computer. A computer’s operating system is its most important program. It is considered the backbone of a computer, managing both software and hardware resources. Operating systems are responsible for everything from the control and allocation of memory to recognizing input from external devices and transmitting output to computer displays. They also manage files on computer hard drives and control peripherals, like printers and scanners.

As per the number of users, there are two types of the Operating Systems. They are1. Single user Operating System.2. Multi-user Operating System.

9

Single user Operating System: At a time, only one user can operate the system. MS Disk Operating System is an example of single user Operating System.

Multi-user Operating System: More than one user can operate the same system simultaneously. The multi-user Operating System is based on the concept of time-sharing. Unix is an example of multi-user Operating System.

Functions of Operating Systems Loads and Executes programs and Utilities. Schedules and controls input and output operations and jobs. Allocates peripherals to programs after checking their availability. Controls storage space for their allocation and de-allocation. Supervises the overall operation of the computer. Searches and destroys viruses. Allocates memory to programs.

10

Input and Output DevicesKeyboard

The keyboard is the most conventional of all input devices. It is used to enter data directly into the computer. The keyboard provides different keys to perform various operations. The arrangement of keys is similar to the typewriter, but it has additional keys. The computer keyboard has three categories of keys. Alphanumeric keys, Special keys and Function keys.

The alphanumeric keys consist of alphabets and numbers and other symbols. The special keys perform specific tasks. Some of the special keys on the keyboard are Enter key, Tab key , Alt key, Ctrl or Control key, Del key, Insert key, Shift key, Num lock key, Caps lock Key and so on.

The function keys are used to perform a set of operations by a single keystroke. The function keys can be used for various functions and depend on the application in use.

Mouse [Mechanically Operated User Serial Engine]: One of the most popular input devices. The mouse is used as a pointing device. It is a

small device, which was developed at the Stanford research institute. There are basically two types of mouse: Mechanical Mouse and Optical mouse

Mechanical Mouse has a small rubber ball in bottom (underneath) that moves against two rollers as it passes across a flat surface. Mechanical sensors detect the movement of the rollers as in X and Y-axis and the cursor on screen is moved accordingly.

Optical Mouse is an advanced computer pointing device that uses a light-emitting diode (LED), optical sensor, and digital signal processing. Movement is detected by sensing changes in reflected light.

Joystick: A joystick is a pointing device with a vertical lever mounted on a base. The lever usually includes buttons called triggers, which activate certain events when pressed. Joysticks are mainly used for computer games and ultrasound scanners in hospitals.

Scanner: A scanner is a light-sensing input device that converts printed text and graphics into a digital form that can be further processed by the computer. It can read image or text printed on a paper and translate the information into the computer. That is, it is used to convert images and text into a stream of data. They are useful for publishing and multi-media applications.

Output DevicesMonitors

It is the most commonly used output device. The monitor is a soft copy output device, it means we can modify contents and data is temporarily on the screen. A monitor technically termed as a visual display unit that transmits information from the computer onto a screen. At present, computer monitors are available in a variety of shapes, designs and colors. However, based on the technology they can be broadly categorized into two types. These include CRT (cathode ray tube) and LCD (Liquid Crystal Technology).

In the recent times, LCD monitors are becoming increasing popular with consumers. Some advantages of using a LCD monitors are compact, light in weight and consume less space. Secondly, these monitors do not consume much electricity and even be operated by using batteries. (TFT is Thin-Film-Transistor, and LCD is Liquid-Crystal Display)

PrintersPrinter is an output device that prints text or images on paper. There are different kinds of

printers, which vary in their speed, cost and printing quality. The two main types of printers are impact printers and non-impact printers.

11

Dot matrix Printer: It is an impact printer use a printer head containing a number of metal pins which strike an inked ribbon placed between the print head and the paper. Characters are formed from a matrix of dots. The speed is usually 30 - 550 characters per second (cps). This is the cheapest and noisiest of the printer family. The standard of print obtained is poor quality. Some print heads have only 9 pins to make the dots to build up a character; some have 24 pins which produce a better resolution.

Laser Printers: It is non-impact printer. The mechanism of laser printer works is similar to photocopier. Laser printers are also known as page printers because they process and store the entire page before they actually print it. Most laser printers can print text and graphics in very high quality resolutions. Laser printers use a laser beam and dry powdered ink to produce a fine dot matrix pattern. It can produce very good quality of graphic images.

Desktop PC: Desktop computer refers to the personal computer and it is most widely used computer in the home and offices. It comes in different styles like vertical tower case and desktop case.  The term desktop refers to the horizontal case and the monitor is usually placed on the top of it.   It has the advantage over the laptop because of the easily availability of the spare parts, lower prices and the greater availability. It can easily upgraded and different components like the hard disk, RAM, optical drive, CD-ROM and the cards can be replaced. 

Laptop PC: A laptop, also called a notebook, is a personal computer. A laptop integrates most of the typical components of a desktop computer, including a display, keyboard, mouse, web camera and speakers into a single unit. A laptop is powered by mains electricity via an AC adapter. A laptop computer has a low power requirements, it requires only a little work space compare to desktop. The unit is portable and you can carry it anytime anywhere, that’s why businessmen, student, and field scientist like the feature of this unit. Laptop computer does not require UPS unit since it has a built-in battery.  Laptop computer is not easy to repair this will require a certified technical person and sophisticated tools.

12

Chapter -5MS-WORD

What is word-processing?Word Processor is a Software package that enables you to create, edit, print and save

documents for future retrieval and reference. Creating a document involves typing by using a keyboard and saving it. Editing a document involves correcting the spelling mistakes, if any, deleting or moving words sentences or paragraphs.

Important features of Ms-wordMs-Word not only supports word processing features but also DTP features. Some of the

important features of Ms-Word are listed below: Using word you can create the document and edit them later, as and when required, by

adding more text, modifying the existing text, deleting/moving some part of it. Margins and page length can be adjusted as desired. Paragraphs or text can be copied /moved throughout the document. Font size and type of fonts can also be changed. Page numbers, Header and Footer can be included. Spelling can be checked and correction can be made automatically. Text can be formatted in columnar style as in the newspaper. Text boxes can be made. Tables can be made and included in the text. Word also allows the user to mix the graphical pictures with the text. Multiple copies of letters can be generated with different addresses through the mail-merge

facility. (Word also provides the mail-merge facility.) Multiple document/files can be merged. Word also has the facility of macros. It also provides online help of any option.

13

Ms-word screen as follows

Important components of the screen

a) Title Bar: The title bar displays the name of the currently active word document.b) Tool Bars: Word has a number of tool bars that help you perform task faster and easier. Two of the most commonly tool bars are the formatting tool bar and the standard tool bar. These two toolbars are displayed just below the title bar.c) Ruler Bar: The Ruler Bar allows you to format the vertical alignment of text in a document.d) Status Bar: The Status Bar displays information about the currently active document. This includes the page number, the column and line number of the cursor position and so on.e) Scroll Bar: The Scroll Bar helps you scroll the content of document.f) Workspace: The Workspace is the area in the document window were you type the text of your document.g) Main Menu: The Word main menu is displayed at the top of the screen as shown in the Figure. The main menu further displays a sub menu.

Shortcut Keys in Microsoft WordShortcut Keys DescriptionCtrl + A Select all contents of the page.Ctrl + B Bold text.Ctrl + C Copy selected text.Ctrl + E Selected text to the center of the screen.

14

Ctrl + I Italic highlighted selection.Ctrl + J Aligns the selected text or line to justify the screen.Ctrl + L Selected text to the left of the screen.Ctrl + P Open the print window.Ctrl + R Selected text to the right of the screen.Ctrl + U Underline text.Ctrl + V Paste.Ctrl + X Cut selected text.Ctrl + Y Redo the last action performed.Ctrl + Z Undo last action.Ctrl + 1 Single-space lines.Ctrl + 2 Double-space lines.Ctrl + 5 1.5-line spacing.F7 Spellcheck and grammar check.Ctrl-O Open a document

Standard Toolbar

New ZoomOpenSave ColumnsPrint Insert tablePrint preview

Spelling Redo Undo

CutCopyPaste

Function of commonly used buttons

Creates a new blank document Opens or finds a file

Saves the file with its current file name Prints the active file

Print preview - Shows how the document will look when you print it.

Spelling, grammar and writing style checker

Cut - Removes the selection from the document and places it on the clipboard

Copy - Copies the selected item(s) to the clipboard

Paste - Places the content of the clipboard at the insertion point

Columns - Changes the number of columns in a document

Undo - Reverses the last command Redo - Reverses the action of the Undo button

15

Displays the Tables and Borders Insert a table into the document

Displays or hides the Drawing toolbar Zoom - Enlarge or reduce the document

Formatting Toolbar

Style ColorFont Highlight Font size BorderBold text Increase indentItalic Decrease indentUnderline BulletsAlign left NumberingCentre Justify

Align right

Function of commonly used buttonsSelect the style to apply to paragraphs

Changes the font of the selected text

Changes the size of text Makes selected text bold

Makes selected text italic Underlines selected text

Aligns to the left Centers the selected text

Aligns to the right Aligns the selected text to both the left and right margins

Makes a numbered list Add, or remove, bullets in a selected paragraph

Decreases the indent Indents the selected paragraph

Adds or removes a border around selected text or objects

Marks text so that it is highlighted and stands out

Formats the selected text with the color you click

16

MAIL MERGE

What is a mail merge?A mail merge is a method of taking data from a database, spreadsheet, or other form of structured data, and inserting it into documents such as letters, mailing labels, and name tags. It usually requires two files, one storing the variable data to be inserted, and the other containing both the instructions for formatting the variable data and the information that will be identical across each result of the mail merge.

Mail Merge requires three types of documents: (a) Main DocumentMain Document is the common letter, which contains the common information for each of the merged document. It also contains the field names, which contain the instructions for carrying out the merge.

(b) Data Source: Data source is a file that contains the names and addresses or any other information that vary with each version of a mail-merge document. For example, a list of names and addresses for a form letter you want to send to a list of clients or other people.

(c) Merge Document: When you merge the main document with data source, a third document called merge document will be produced. The merge document can be merged to the screen to view letters along with addresses;

Mail Merge HelperThe Mail Merge Helper guides you through the process of doing a mail merge. This involves creating and editing main document; creating a new data source or opening an existing data file; and merging the data source with main document. To use Mail Merge Helper, select Tools -> Mail Merge command on the menu bar. The Mail Merge Helper dialog box appears.

MS EXCELMS-Excel is a Windows based application package. It is quite useful in entering, editing, analysis and storing of data. Arithmetic operations with numerical data such as addition, subtraction, multiplication and division can also be done with Excel. You can sort the numbers/characters according to some given criteria and solve simple financial, mathematical and statistical formulas.

What is spreadsheet

A spreadsheet, also known as a worksheet, contains rows and columns and is used to record and compare numerical or financial data. Spreadsheets can be used in any area or field that works with numbers and are commonly found in the accounting, budgeting, sales forecasting, financial analysis, and scientific fields.

The advantage of using computerized spreadsheets is their ability to update data and perform automatic calculations extremely quickly. On a computerized spreadsheet, the intersection of a row and a column is called a cell. Rows are generally identified by numbers - 1, 2, 3, and so on - and columns are identified by letters, such as A, B, C, and so on. The cell is a combination of a letter and a number to identify a particular location within the spreadsheet, for example A3.

17

Features Automatic number formatting Auto summation Auto formatting Spell checking Drag and drop worksheet rearrangement Auto fill Powerful toolbar Macros Scenario manager Excellent charting features

Excel FormulasABS: Returns the absolute value of a number. The absolute value of a number is the number without its sign.

Syntax: ABS (number)Eg: ABS (2) equals 2

ABS (-2) equals 2

SUM: Adds all the numbers in a range of cells.Syntax: 1. SUM (number1, number2, ...)

2. SUM (Cell range)

Eg: a) SUM (3, 2) equals 5b) If cells A2: E2 contain 5, 15, 30, 40, and 50 =SUM (A2: C2) equals 50

AVERAGE: Returns the average of the arguments.Syntax: 1. AVERAGE (number1, number2, ...)

2. AVERAGE (Cell range)AVERAGE (A1: A5) equals 11

PRODUCT: Multiplies all the numbers given as arguments and returns the product.Syntax: PRODUCT (number1, number2, ...)

Eg: If cells A2: C2 contain 5, 15, and 30:PRODUCT (A2: C2) equals 2,250

MAX: Maximum value in the cell rangeEx: MAX (23,76,34) Returns 76

MIN: Minimum value in the cell rangeEx: MIN (23,76,34) Returns 23

18

Introduction to DBMS

The motivation for studying DBMS is provided by the huge growth in the amount of information that has to be managed on a daily basis by almost every organization. Banks have to keep track of numerous financial transactions, airlines have to ensure that all the travel agents have access to the current status on flights, universities have to keep track of student records, and various scientific organizations have to keep track of very large databases. One option for managing this data is to keep information in flat files. However, this does not turn out to be very efficient if you want functions such as safe, concurrent access of the data, different security levels for individual records, various types of queries, efficient searches, etc. A Database Management System is a collection of software that enables users to create and manage databases.

DBMS is a centralized system which provides a common interface between the data and the various front-end interface programs in the application. It also provides a central location for the whole data in the application to reside.

Database Management System (DBMS)

When all the required data of an organization is integrated along with the required details for proper interpretation it constitutes a database system The integration of the required data varies and depends on the organization and the various applications which use this data

In order to satisfy the overall requirement of the user a special kind of software tool called Database Management system (DBMS) is required

Thus a DBMS is software which helps the user to perform all related operations such as defining storing retrieving and modifying information from a database. Database management systems have a variety of functions

Advantages of a Database Management system are:

Minimal Data Redundancy: Since the whole data resides in one central database, various programs can access data in different data files. Hence data present in one file need not be duplicated in another. This reduces data redundancy.

Data Consistency: Since data redundancy is reduced it leads to better data consistency as conflicting operations will be completed avoided.

Data Integration: Since related data is stored in one single database, enforcing data integrity is much easier. Moreover, the functions in the DBMS can be used to enforce the integrity rules with minimum programming in the application programs.

Data Sharing: Related data can be shared across programs since the data is stored in a centralized manner. Even new applications can be developed to operate against the same data.

Enforcement of Standards : Enforcing standards in the organization and structure of data files is required and also easy in a Database System, since it is one single set of programs which is always interacting with the data files.

19

Application Development Ease : The application programmer need not bother about issues like concurrent access, security, data integrity, etc. The programmer only needs to implement the problem. This brings in application development ease.

Better Controls : Better controls can be achieved due to the centralized nature of the system. Data Independence : The architecture of the DBMS can be viewed as a 3-level system

comprising of the internal or the physical level, the conceptual level and the external level which is the level of the application programs or the end user. Operations at one level do not affect the functioning at other levels.

Reduced Maintenance: Maintenance is less and easy, again, due to the centralized nature of the system.

What is database?

A database is a common terminology used in day to day environment. A database is a collection of a large amount of related data organized and recorded in a format that establishes a relationship in a form that can be handled by a computer.

A database may also be defined as a collection of interrelated data stored together to serve multiple applications; the data is stored so that it is independent of programs which use the data; a common and controlled approach is used in adding new data and modifying and retrieving existing data within the databasease. The data is structured so as to provide a foundation for future application development.

A database is a data structure that stores organized information. The database is organized by fields, records and files. Most databases contain multiple tables, which may include several different fields. For example, a company database may include tables for products, employees, and financial records. Each of these tables would have different fields that are relevant to the information stored in the table.

Field: A space allocated for a particular item of information, for example, one for your name, income, and so on. In database systems, fields are the smallest units of information you can access.

Record: A record is a collection of fields. Records are composed of fields, each of which contains one item of information. A set of records constitutes a file. For example, a personnel file have three fields: name, address, phone number field

Table: It refers to data arranged in rows and columns. In relational database management systems, all information is stored in the form of tables.

Types of Table RelationshipsA relationship works by matching data in columns, usually columns with the same name in both tables. In most cases, the relationship matches the primary key from one table, which provides a unique identifier for each row, with an entry in the foreign key in the other table.

There are three types of relationships between tables. One-to-One Relationships One-to-Many Relationship

20

Many-to-Many Relationships

One-to-One RelationshipsIn a one-to-one relationship, a row in table A can have no more than one matching row in table B, and vice versa. A one-to-one relationship is created if both of the related columns are primary keys or have unique constraints.

For example, an MP can have only one constituency, and a constituency can have only one MP

One-to-Many RelationshipsA one-to-many relationship is the most common type of relationship, a row in table A can have many matching rows in table B, but a row in table B can have only one matching row in table A.

For example, a mother can have more than one child, but a child can have only one biological mother

Many-to-Many RelationshipsIn a many-to-many relationship, a row in table A can have many matching rows in table B, and vice versa. You create such a relationship by defining a third table, called a junction table, whose primary key consists of the foreign keys from both table A and table B.

For example, an author can write more than one book and a book can be written by more than one author

21

Cyber laws and Information Technology ActIntroduction

Information technology has been playing an important role in improving business performance. Now a day, business transactions are being made with the help of computers, In fact, computers have been using in large scale in business to create, transmit and store information in the electronic form, instead of traditional paper documents. Because, it is easy to create document, store business data, retrieval of any unwanted information and speedy communication of business information. Apart from these advantages, there are innumerable benefits from use of computers in business.

But, unfortunately, there was no proper legal frame work for the use of computers in business. However, In recent days, the government has been making attempts to enact suitable laws to facilitate electronic commerce and also to facilitates electronic governance by means of reliable electronic records. Thus, this law provides legal recognition for transactions carried out by means of electronic commerce which involves electronic communication and storage of information to facilitate electronic filing of documents with the government agencies. It is also called as cyber law.

Meaning of cyber lawCyber law means laws which are concerned with communication and automotive control

system. In other words, it is a law which governs the use of computers and the internet.

Advantages of cyber lawThe following are advantages of cyber law.

It gives legal recognition to transactions carried out by means of electronic data. It provides legal recognition to electronic means of communication. It facilitates electronic filing of documents with government departments. It provides legal sanction to electronic fund transfers between banks and financial

institutions. It gives legal recognition to digital signatures for authentication of any information. It facilitates electronic storage of data. It provides legal sanction for keeping books of accounts by banks in electronic form.

Cyber CrimesCyber crimes may be defined as “any crime committed with the help of computer and

telecommunication technology with a view to influencing the functioning of computers or computer systems”.

Kinds of cyber crimesFollowing are the some types of cyber crimes committed by the cyber criminals.

1) Hacking: It is the most common type of cyber crime which is committed all over the world. Hacking with computers is a cyber crime committed by a person with the intention to cause wrongful loss or damage to the public or any other person through destroy or delete or alter any information residing in a computer resource. So, a hacker is a person who breaks in or trespasses a computer system.

Any person who commits hacking is punishable with imprisonment upto three years or with a fine upto two lakh rupees or with both.

22

2) Cracking: Means ‘illegal access’ it is a cyber crime which includes unlawful gaining entry into instructing or communicating with the logical, arithmetical or memory function resources of a computer, computer system or computer network.

Cracking also includes the entering of another computer or computer system where it is connected with public telecommunication net work or to a computer system on the same net work like LAN [ local Area Network] or internet with are organization.

3) Fraud on the internet: Fraud on the internet is a form of white collar crime. The internet provides an opportunity to business firms and individuals for marketing their products on the net. In this method, It is easy for the persons with fraudulent intention to make their messages look real and credible and cheat. Most of the frauds on the internet relate to investment schemes.

4) Online investment newsletters: News letters on the internet provide the investors with free advice recommending securities in which they should invest. But, sometimes, such news letter contains completely bogus recommendations and cause great loss to the innocent investors.

5) E-mail scans: E-mail containing useless and bogus information known as junk mail. Fraudulent people very often create such junk mail and spread information about bogus investment schemes with the intention on to cheat investors.

6) Security related crimes: Network security is becoming a major concern with the growth of the internet. Sometimes, private confidential information can be made available easily to the public on internet. Confidential information resides on the network. The users of network attack on the internet and get such information.

7) Tampering with computer source document: It is a cyber crime committed by a person through intentional concealment, destroy code or alteration of any computer source used for a computer, computer programme, computer system, or computer net work.

Any person who commits such crime shall be punishable with imprisonment upto three years or fine upto two lakh rupees or with both.

8) Internet protocol spoofing: An internet protocol attack takes place when an attacker outside the net work pretends to be a trusted computer either by using an internet protocol address which is within its range or by using an external internet protocol address to which need to provide access to specified resources on net work. Normally, an internet protocol spoofing attack is confined to the insertion of data or commands into an existing stream of data passed between the client and the server application.

9) Password Attacks: There are several methods which can be used for committing cyber crime in the form of pass word attacks. These methods are such as brute force attacks, Trojan horse programmes etc. Usually, pass word attacks refers to repeated attempts to identify a user password or account. Such repeated attempts are known as brute force attacks.

The main object of password attacks is to distribute sensitive information to computers or others who use it to the disadvantage of the owners. Such pass word attacks are made mostly for theft of information.

10) Credit card fraud: Credit card also known as plastic money. Credit card is most likely to be misused by the fraudulent persons who cause a great loss to the credit card owners.

11) Publishing false digital signature: If, any person who knows that a digital signature certificate is erroneous in material particulars and publishes it, he is under the guilt of cyber crime, such a person is punishable with imprisonment for a term that may extend to two years or with a fine of one lakh rupees or with both.

23