DEFINE COMPUTER.pdf

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DEFINE COMPUTER

Computer is an electronic device that manipulates data, accepts and stores the input

data for further use, processes the data and produces the output data in required

format.

HISTORY

Charles Babbage is called as “Father of Computer”.

Alan Turing is regarded as the father of modern computer science .Electronic Numerical

Integrator and Calculator (ENIAC) is considered to be the first purpose electronic digital

computer.

Atanasoff Berry Computer (ABC) was the world’s first unprogrammable electronic digital

computer

Speed, Reliability and Storage are the parameters on which the power of the

computer is judged.

COMPUTER GENERATIONS

First Generation (1946-1959)

Vacuum tubes were used.

Batch processing operating system was used.

Machine and Assembly languages were used.

Used for scientific; later simple business system.

Some computers of this generation were: ENIAC ; EDVAC; UNIVAC; IBM-701 ; IBM-650

Second Generation (1959-1965)

Transistors were used.

Multi-Bag remaining, Time sharing operating system were used.

Magnetic cores were used as primary memory and magnetic tape and magnetic disks as

secondary storage devices. Main memory was 100KB.

Assembly language and high-level programming language like FORTRAN, COBOL, Algol were

used.

Used for extensive business applications, engineering design optimization scientific research.

Some computers of this generation were: IBM 1620; IBM 7094 ; CDC 1604 ; CDC 3600 ;

UNIVAC 1108

Third Generation (1965-1971)

Integrated circuits were used in place of transistors.

Remote processing, Time-sharing, Real-time, Multi-programming Operating System were

used.



High-level languages FORTRAN-II TO IV, COBOL, PASCAL PL/1, BASIC, ALGOL-68, etc were

used.

Used for Database management system and online systems.

Some computers of this generation were: IBM-360 series; Honeywell-6000 series; PDP

(Personal Data Processor); IBM-370/168; TDC-316.

Fourth Generation (1971-1980)

Very Large Scale Integrated (VLSI) circuits were used.

Semiconductor memory and Winchester disk were used as the memory devices.

Time sharing networks were used

Fortan 77, Pascal, Cobol high level languages were used.

Concept of internet was introduced, computers became easily available.

Some computers of this generation were: DEC 10; STAR 1000; PDP 11; CRAY-1 (Super

Computer); CRAY-X-MP (Super Computer)

Fifth Generation (1980-till date)

VLSI technology became ULSI (Ultra Large Scale Integration) technology

Introduced AI(Artificial Intelligence) concept which is an emerging branch of Computer

Science that interprets means and methods of making computers think like human beings.

C, C++, Java, .Net -higher level languages are used.

Some computers types of this generation are: Desktop ; Laptop ; NoteBook ; UltraBook ;

ChromeBook

TYPES OF COMPUTER

1. PC (Personal Computer) or Micro Computer: A PC can be defined as a small, relatively

inexpensive computer designed for personal use. Personal computer is referred to as a

micro computer, a computer that uses a microprocessor for its processing. PCs are used in

Businesses for word processing, a desktop publishing, and for running spreadsheet and

database management applications. The most popular use for personal computers at home

is for playing games and surfing the Internet. Market for personal computer is extending

very fastly.

2. Mini Computer: The use of mini computers has become less popular. It was designed to

perform specific tasks. It is a midsize computer. Personal computers have replaced mini

computers.

3. Mainframe: Main Frame computers are expensive and large sized. Mainframe computers

has time sharing and Multi tasking Techniques due to which it is capable of supporting

hundreds, or even thousands, of users simultaneously. A specific type of environment is

required for the working of the computer.

4. Super Computer: They are very powerful, expensive as well as the fastest computers.

Supercomputers are used for the applications that require large amounts of mathematical



calculations. For example, weather forecasting, scientific simulations, (animated) graphics,

fluid dynamic calculations, nuclear energy research, electronic design, and analysis of

geological data.

BASIC COMPUTER OPERATIONS

1. Input- The process of entering the data into the system. Data are the raw facts entered into the

computer. Input can be in the form of Programs, Commands and User’s Response.

*Programs-Set of Instructions.

*Commands-Special codes or keywords entered by the user to perform a specific task.

*User’s Response- User’s response to the computer in the form of yes or no.

2. Storage-The process of saving the data and instructions permanently.

*Instructions-It is the type of action taken on the input data.

3. Processing- The process of performing arithmetic, logical operations on the data in order to

convert it into useful information.

* Information- It is the meaningful data or the final result which has been processed.

4. Output- The process of displaying the useful information to the user.

FUNCTIONAL UNITS

1. Arithmetic Logical Unit (ALU): ALU performs arithmetic and logic operations like Addition,

subtraction, multiplication, division, logic and comparison. It is a part of execution unit.

2. Control Unit (CU): Control unit controls the operations for all parts of computer. It does not

perform any data processing operations. It gives command to transfer data from the input device

into memory and from memory to ALU. It performs various functions

Fetch-It gets an instructions from the main memory

Decode-Translates instructions into computer commands Execute-It processes the commands Store- It stores the result into the main memory

Functions of this unit are:

Controls and transfers the data and instructions to the other parts of a computer.

It manages and coordinates all the units of the computer.

It obtains the instructions from the memory, interprets them and directs the operation of

the computer.

It communicates with Input/output devices for transfer of data or results from storage.

It does not process or store data.



3. Central Processing Unit: CPU processes whatever input is entered into the computer. It is the part

of the computer where the entire work is performed. It is also known as the brain of the computer.

The ALU and the CU of a computer system are jointly known as the Central Processing Unit.

Machine cycle

Fetch-In a machine cycle, instructions is fetched from the main memory.

Decode-The fetched instruction is translated into computer commands.

Execute-The command is actually processed.

Store-In this cycle, the result is written into the main memory.

Processor Speed-

Processor speed is measured in megahertz (Mhz) or in gigahertz. Processor speed is affected by

system clock rate. The rate of an electronic pulse is used to synchronize processing.

Components of Computer

INPUT Devices: The data into computer is entered through the Input devices. It translates the data

into computer understandable form. Below are the examples of the Input devices-

1. Keyboard-The keyboard is the most common and popular input device.

Usually Keyboards are of two sizes 84 keys or 101/102 keys, but now 104 keys or 108 keys keyboard

is also available for Windows and Internet.

Computer Keys

-Typing Keys: Includes letter A-Z and digits 0-9.

-Numeric Keypad: It is used to enter numeric data or cursor movement. Generally, it consists of a set

of 17 keys.

-Function Keys: Arranged in a row along the top of the keyboard. Each function key has unique

meaning and is used for some specific purpose.

-Control keys: Provide cursor and screen control. Includes Home, End, Insert, Delete, Page Up, Page

Down, Control (Ctrl), Alternate (Alt), Escape (Esc).

-Special Purpose Keys: These are Enter, Shift, Caps Lock, Num Lock, Space bar, Tab, and Print Screen.

2. Mouse- Mouse is the most popular pointing device. It has two buttons called left and right button

scroll bar is present at the mid. Mouse can be used to control the position of cursor on screen, but it

cannot be used to enter text into the computer.

*Pointing Device-Any human interface device which allows a user to input spatial data into a

computer.



3. Track Ball: It can be used as an alternative to the mouse. In trackball, ball is half inserted and by

moving fingers on ball, pointer can be moved. The user just rolls the track ball only.

4. Joystick – Joystick is a pointing device which is used to move the cursor on the monitor. It is used

in Computer Aided Designs (CAD) and Playing games.

5. Scanner- It is uses to capture a page and converts it into digital form.

6. Digital Camera

7. Microphone-It is used as a sound input to input sound. It can be used to enter text to any word

processing application with the voice recognition software in the computer.

8. Touch Screen-Input is given by touching the screen. Touch screen is used in many mobile phones.

They are used in cash machines and shopping centres.

9. Magnetic Ink Card Reader - MICR input device is majorly used in bank to process a large number

of cheques. The bank's code number and cheque number printed on the cheques with a special ink

consisting of particles of magnetic material which are machine readable. MICR is fast and less error

prone.

10. Optical Character Reader (OCR) - It is used to read a printed text. OCR scans text optically

character by character and converts them into a machine readable code.

11. Bar Code Reader- It is used for reading bar coded data (light and dark lines) Bar. Bar Code Reader

scans a bar code and converts it into an alphanumeric value.

Output Devices-Output devices translate the computer's output which has been processed into

useful information.

1. Visual Display Unit (VDU) Or Monitor-It is the main output device of the computer. The output

displayed on screen is called soft copy. There are two kinds of viewing screen used for monitors:

-Cathode-Ray Tube

-Flat-Panel Display

2. Printers - Most common Input device which is used to print information on paper. The output

printed on paper is known as a hard copy.

There are two types of Printer:

-Impact Printer

-Non-impact Printer

Impact Printers - The printers that print the characters by striking against the ribbon and onto the

paper are called impact printers.

Characteristics of Impact Printers are the following:



Low consumable costs

Very noisy

Useful for bulk printing due to low cost

There is physical contact with the paper to produce an image

Types of Impact Printers

Dot Matrix Printer

Daisy Printer

Line Printer

Drum Printer

Chain Printer

Non-Impact Printer - These printer prints the characters without striking against the ribbon and onto

the paper is called Non-impact Printers. These printers print a complete page at a time. They are also

called as Page Printers.

Characteristics of Non-impact Printers:

Faster than impact printers.

They are not noisy.

High quality.

Support many fonts and different character size.

Types of Non- Impact Printers

Laser Printer

Ink-jet Printers

3.Data Projectors- It projects the image onto a wall screen. Watching a movie in a theatre is an

example of projector.

4. Speaker- It gives you the same output from your computer.

5. Headphones- They are similar to speakers, they are worn on to ears.

6. Floppy disk- Floppy disk is used to record information. The information recorded can be used

later.

COMPUTER MEMORY-

Computer’s internal storage area which holds the data and instruction during processing is called the

Computer Memory. Both programs and data are stored in the binary form. The memory is divided

into large number of small parts called cell. Each location or cell has a unique address, which varies

from zero to memory size minus one. The memory of computer is measured in Byte, Kilobyte,

Megabytes and Gigabytes.



Types of Memory

1. Primary Memory

When the data is entered into a computer, it gets stored in the Primary memory. Primary Memory

holds the data and instruction on which computer is currently working and the intermediate results.

When power is switched off it lost all data this happens due to its limited capacity.

-It is also known as main memory. It is also known as the temporary memory.

-It is volatile memory as the data is lost when the computer is switched off.

-It is faster than Secondary memory.

The two basic kind of Primary Memory are:

1. RAM (RANDOM ACCESS MEMORY)

All the active data and programs are stored in RAM so that they are easily available and accessible by

the CPU.

It is volatile which means it lost its data when the power is switched off.

RAM can hold only small amount of data.

It is also known as read and write memory.

RAM is of two types

Static RAM: The static RAM retains its memory contents as long as power is applied.

Dynamic RAM: D-RAM continually needs to be refreshed in order for it to maintain the data.

2. ROM (READ ONLY MEMORY)

ROM is a non-volatile memory; it retains its contents even without a power source. The data written

on ROM is permanent. The data stored in ROM cannot be changed.

Bootstrap is an operation that is required to start computer, during this process instructions are

loaded from the ROM.ROM is more reliable and cheaper than RAM.

Following are the various types of ROM:

MROM (Masked ROM) -The first ROMs were hard-wired devices which contained a pre-

programmed set of instructions. They were known as masked ROMs. They were inexpensive

ROM.



PROM (PROGRAMMABLE ROM) - PROM is read-only memory which can be modified only

once by a user. The data is entered by user in the blank PROM using a PROM programmer.

PROM is not erasable.

EPROM (ERASABLE AND PROGRAMMABLE ROM)-The EPROM can be erased by exposing it to

ultra-violet light for duration of up to 40 minutes.

EEPROM (ELECTRALLY ERASABLE AND PROGRAMMABLE ROM)-The EEPROM is programmed

and erased electrically. It can be erased and reprogrammed about ten thousand times.

Both RAM and ROM make up the primary memory of the computer.

2. Secondary Memory or Auxiliary Memory

Secondary Memory is a non volatile which means data is stored permanently even if the power is

switched off. It is used for storage of the data in computer.

The Information in the secondary memory is not directly accessible to CPU, as it is moved from the

secondary memory to the primary memory first and then to the CPU. It is also known as the

permanent memory.

Common Examples of secondary Memory are:

Magnetic Tape: Long plastic tape coated with magnetic material. The speed of data access

can be slow, when the tape is long. This is used for mainly major backups of large amounts

of data.

Floppy Disk: It is plastic disk coated with magnetic material on which the information stored

and is directly accessible.

Hard Disk: A hard disk can store data from 10 megabytes to several gigabytes.

Cache Memory- Cache memory acts as a buffer between memory and CPU. A cache is a

temporary storage area where regularly accessed data is stored for speedy access. It is faster

than the main memory and consumes less access time. The space in cache memory is limited

and it is very expensive.

Optical disk

In an optical disk, data are arranged in a spiral groove on starting from the centre of the disk.

The different types of optical disk use different materials and methods to absorb and reflect the light.

Digital data is in the form of ‘0’ and ‘1’.

Disk Format Tracks- A track is a circular ring on one side of the disk and each track has a number.



Sectors- A disk sector is a wedge shaped piece of the disk. A track sector is the area of intersection of a track and sector. Clusters- A cluster is a set of track ranging from 2 to 32. 1 cluster is the minimum space used by any read or write. Cylinders- A cylinder is a set of matched tracks.

Flash memory- They are solid state devices that read and write data electrically, instead of magnetically. The devices like digital cameras, digital camcorders and cell phones use compact flash, smart media or another flash memory card.

USB drive- They are known as flash drive, flash pen, thumb drive, key drive and mini- USB drive. They are small in size and can plug into a USB port on the computer. They have storage capacities from 8GB to 1GB.

Removable Hard drives- They are special drives that compress data. They are regular external hard drive that can be used for backup.

Optical cards- A chip on this type of card holds information like health records and other auto repair records. They can hold more data than the smart cards as they don’t need to do any processing.

MEMORY UNITS

The data is stored in the storage unit. The storage capacity is expressed in terms of Bytes.

Following are the main memory storage units:



1. Bit One binary digit

A binary digit is logical 0 & 1 representing a passive or an active state of a

component in an electric circuit.

2. Nibble4 bits

A group of 4 bits is called nibble

3. Byte8 bits

A group of 8 bits is called byte. A byte is the smallest unit, which can represent a

data item or a character.

4. Word16 to 64 bits

The length of a computer word is called word-size or word length and it may be as

small as 8 bits or may be as long as 96 bits .A computer stores the information in the

form of the computer words.

5. Kilobyte(KB)1024Bytes

6. Megabyte(MB)1024 KB

7. Gigabyte(GB)1024 MB

8. Terabyte(TB) 1024 GB

9. Petabyte(PB) 1024 TB

Physical Components:- Many physical components are involved in processing. They

are:-

1. Microprocessors

2. Memory Devices

3. Motherboard

Microprocessor- The CPU, ALU and memory is contained in a single silicon chip known as the

Microprocessor. It is located on a large circuit board, known as the motherboard. The

microprocessor is very small in size.



Memory Devices- Memory devices include Vaccum tubes, core and Semi Conductor.

MOTHERBOARD

The motherboard has a number of ports to connect all of the parts of a computer together. A motherboard connects CPU, memory, hard drives, optical drives, video card, sound card and other ports and expansion cards directly or via cables. It can be considered as the backbone of a computer.

Motherboard contains ports to connect all of the internal components.

Port-A computer port is a physical docking point using which an external device can be connected to

the computer.

Following are the various types of important ports

Serial Port-It is used for external modems and older computer mouse.

Parallel Port-It is used for scanners and printers. It is also known as the printer port.

PS/2 Port-It is used for old computer keyboard and mouse. It is also called a mouse port.

Universal Serial Bus (or USB) Port-It connects all kinds of external USB devices such as external hard

disk, printer, scanner, mouse, keyboard, etc.

VGA Port-Connects monitor to a computer's video card.

Firewire Port-Transfer large amounts of data at very fast speed.Connects camcorders and video

equipments to the computer

Modem-Connects a PC's modem to the telephone network.

Ethernet Port-Connects to a network and high speed Internet.Connects network cable to a

computer.

Game Port-Game port connects a PC to a joystick. It is now replaced by USB.

Digital Video Interface, DVI port connects a Flat panel LCD monitor to the computer's high-end

video graphic cards. Very popular among video card manufacturers.

Sockets-Connect microphone, speakers to sound card of the computer

Connectors-Connectors is used to connect hard drives, floppy drives and CD- ROM

Memory Slot- There are four short slots for the semi conductor memory.

Power connection-This is the slot where power supply connects to the motherboard.

Processor Socket- This is the slot where the processor plugs into the motherboard.



SOFTWARE

Software is a set of instructions that guides computer to process its job. Computer software

cannot be touched. The functions like controlling the hardware, performing computations,

human interactions etc, are performed by computer software.

Types of software: A. System Software

B. Application software

C. Utilities Software

SYSTEM SOFTWARE:

System software is a collection of programs designed to operate, control and extend the processing

capabilities of the computer itself. Operating System, Compiler, and Interpreter etc are the examples

of system software.

APPLICATION SOFTWARE

Application software is a setoff programs designed for a particular application.

Examples of Application software are: Microsoft word, Microsoft Excel, Railway reservation

software.

UTILITIES SOFTWARE

This software is requested by other application programs. Example of utility software- Antivirus etc.

Hardware

Hardware is the part of computer that can be seen and felt by touching. The other computer

equipments are called peripherals. Printer, Modems, scanners etc are the examples of hardware.

OPERATING SYSTEM

An operating system is a set of programs which performs various types of functions to manage and

organize files.

Operating system acts as a link between the software and the computer hardware.

It is specialised software that controls and monitors the execution of all other programs that reside in the computer, including application programs and other system software.

Common Operating System: MS DOS, Windows XP, Windows 7, UNIX, LINUX.



Operating system can be categorised as-

Multi-user- Allows two or more programs to run at the same time.

Multi-tasking-Allows one or more program to run simultaneously

Multi processing- Allows a program on more than one CPU.

Multi threading-Allows different part of a single program to run simultaneously

Real time processing-It responds to the input instantly. Real time processing is use to control

machinery, scientific instruments and industrial systems.

Functions of Operating system:-

-Processing commands

-Controlling and execution of programs

-Managing devices (storage and retrieval of files)

The functions involved in the management of resources are as follows-

Process Management

Memory Management

Input/Output Management

Information management

User interface



MICROSOFT WORD FEATURES MICROSOFT WORD

Microsoft word is an excellent word processor that allows the user to create letter, resume, report and announcements. File Extension for MS Word : .doc or .docx . A word processor is similar to a conventional type writer with some additional features. It provides a general set of tools entering, editing and formatting text.

MICROSOFT WORD FEATURES Header and Footer: Header and footer is text or graphics that appear on the top and

bottom of a page. Header and footer contains the page number, the date of a company logo that is usually printed at the top or bottom of each page in a document.

Title Bar: The Title bar shows the name of the file on which you are working. In this there are three buttons on the right hand side: Minimize (reduces the window down), Maximize (to make the window full size) and Close (to close the window).

Menu Bar: The Menu Bar is placed below the Title bar and it consists of various options.

File Menu: From File menu user can perform the functions such as Create a new document, open existing file, save files and print.

Home Tab: It provides options that can change the font, size, colour, alignment, bullets and numbering, organization and style of the text.

Insert Tab: It provides the options to insert Tables, links picture, clipart and symbols. Page Layout Tab: It includes Themes, page setup, Page Background. Ruler: It shows the width of the document which can be increased or decreased. Workspace: It is the area where the text can be entered. Thesaurus: It is used to find the synonym for a word in the document. Spell check: It is used to check the spelling and grammar mistakes and also provide

the possible alternative for incorrectly spelt word.

List of Commonly used key that have special functions in MS Word : 1. Backspace key: This deletes letters backward. 2. Delete key: This deletes letter forward. 3. Shift key: This when press with another key will perform a secondary function. 4. Spacebar key: This enters the space between the words or letters. 5. Tab: This will indent what user type, or move the text to right. The default indent distance is usually ½ Inch. 6. Caps Lock : This key when pressed , will capitalized every letter 7. Control (Ctrl): This when pressed WITH another key, performs a shortcut. 8. Enter: This either gives a new line, or executes a command. 9. Arrow Keys: Used to navigate through a document or page.



MICROSOFT WORD SHORTCUTS

Function Keys

NAME OF

THE KEY Function key

Ctrl +Function

key Shift+ Function key Alt+ Function key

F1

Open the help

Window -

Display the reveal

formatting pane Go to next field

F2

Move text or

graphics

Switch to print

preview view Copy text -

F3 - Cut to the spike

Change the case of

letters Creating a new building block

F4

Repeat the last

action Close the window

Repeat a find or go to

action Exit word

F5

Display the Go

To dialog box -

Move to the last

change Restore the Word Window size

F6

Go to the next

pane or frame

Go to the next

window

Go to the previous

pane or frame

Move form an open dialog box back to the

document ,for dialog boxes as such as find and

replace that support this behaviour

F7

Show the

spelling dialog

box -

Show the thesaurus

task pane Find the text or grammatical error

F8

Extend a

selection - Shrink a selection Run a Macro

F9

Update the

selected fields

Insert an empty

field

Switch between a

field codes and its

result Switch between all field codes and their results

F10

Show the key

tips on the

ribbon

Maximize the

document

window

Display a shortcut

menu Maximize the world window

F11 Go to the next

Lock a field Go to the previous

Display the Microsoft Visual Basic code window



field Field

F12

Show the save

as dialog box

Show the open

dialog box

Save the changes to

the document -

Basic Shortcut keys Keys

Name of the Key Description

Ctrl +N Starts a new Blank Document

Ctrl +O Display the open Dialog Box

Ctrl +W Close the Active Document

Ctrl +S Save a document

Ctrl +P Display the print Dialog Box

Alt +Ctrl +I Switch to and from Print Preview view

Alt +Ctrl +P Switch to Print Layout View

Ctrl +F Display the find dialog box

Ctrl +H Display the Replace dialog box

Ctrl +G Display the Go To dialog box

Ctrl +Z Undoes the last action

Ctrl +C Copy selected text and graphics to the office clipboard

Ctrl +X Cut selected text and graphics to the office clipboard

Ctrl +V Paste the post recent addition to the office Clipboard

Ctrl +F9 Insert a Blank field

Shift +Enter Start a new line in paragraph

Ctrl + Enter Insert a page break

Ctrl + A Selects the entire document

Ctrl + D Opens the font dialog box to change the formatting of characters

Shift + F3 Changes the case of letters

Ctrl + B Applies or removes bold formatting



Ctrl + U Applies or removes underlining

Ctrl + I Applies or removes italics formatting

Ctrl + 1(One) Sets a single line spacing

Ctrl + 2 Sets a double line spacing

Ctrl + 5 Sets 1.5 line spacing

Ctrl + 0(zero) Adds or removes one line space preceding a paragraph

Ctrl + E Switches a paragraph between centred and left alignment

Ctrl + J Switches a paragraph between justified and left alignment

Ctrl + R Switches a paragraph between Right and left alignment

Ctrl + L Applies left alignment

Ctrl + M Indents the paragraph from the left

Ctrl + T Creates hanging Indent

Ctrl + Q Removes a paragraph formatting

Ctrl + Del Deletes word to the right of the cursor

Ctrl + Backspace Deletes word to the left of the cursor

Ctrl + End Moves cursor to the end of the document

Ctrl + Home Moves cursor at the beginning of the document

Ctrl + Alt + 1 Changes text to heading 1



Alt + Ctrl + F2 Open new document

Shift + Insert Paste

Ctrl + Shift + F6 Opens another Microsoft Word document

Alt + Shift + D Insert the current date

Alt + Shift + T Insert the current time



Ctrl + K Inserts link

Ctrl + Shift + F Change the font

Ctrl + Shift + * View or hide non printing characters

MICROSOFT EXCEL

It is a part of MS Office. Microsoft Excel is a spreadsheet application. It features Calculation,

graphic tools, Pivot tables and a macro programming language called Visual Basic for

Application (VBA).

MICROSOFT EXCEL FEATURES

Worksheet : It is a grid of cells made up of horizontal rows and vertical columns . It contains 65536 rows and 256 columns.

Row Number : Each row is given a number . Column Letter : Each column is given a letter starting from A, …,Z ,AA,…..ZZ and so

on. Cell : It is basic unit of worksheet where numbers ,text ,formulae etc ., can be place. Cell Pointer : It is a cell boundary that specifies which cell is active at that moment. Current Cell : It is a cell which is active. Range of Cell : It is a group of contiguous cells that forms a rectangular area in

shape. Work Book : A worksheet is a grid of cells made up of rows and columns . Data in Worksheet : Three types of data can be entered numbers/characters ,text

and formulae. Formula : It is a sequence of values , cell address ,names functions or operators in

cell that produces a new value form existing values. Cell Referencing : Each cell in worksheet has a unique address ,when cell address is

referred in formulas it is called Cell Referencing . Relative Referencing: Cell Referencing in which the cells are refereed by their

relative position in which worksheet relative to a particular cell. Absolute Referencing : Cell referencing in which the cells are referred by their fixed

position in the worksheet. Mixed Referencing : Combination of relative and absolute referencing . Functions : Functions are predefined formulae, that perform calculations by using

specific values called arguments.



Structure: The structure of a function begins with the function name, followed by an opening parenthesis argument for the function separated by commas and a closing parenthesis.

Charts: Charts are the pictorial representation of worksheet data. Area chart: An area chart emphasises the magnitude of change over time. Column chart: A column chart shows data changes over a period of time. Bar chart: It illustrates comparisons among individual items. Line chart: It shows trends in data at equal intervals.

MICROSOFT EXCEL SHORTCUTS

Shortcut Keys

Shortcut keys Description

F2 Edit the select cell

F5 Go to the specific cell

F7 Spell check selected text and /or document

F11 Create a chart

Ctrl +Shift+; Enter the current time

Ctrl+; Enter the current date

Alt+Shift +F1 Insert a new worksheet



Shift+F3 Open the excel formula window

Shift+F5 Bring up search box

Ctrl+A Select all the contents of the worksheet

Ctrl+B Bold highlighted section

Ctrl+I Italic highlighted section

Ctrl +K Insert Link

Ctrl +U Underline highlighted section

Ctrl +5 Strike through highlighted section

Ctrl+P Bring up the control dialog box to begin printing

Ctrl +Z Undo last section

Ctrl + F9 Minimize current window

Ctrl+ F10 Minimize currently selected window

Ctrl +F6 Switched between work books/ windows

Ctrl+Page Down/Ctrl+Page

Up Move to the next / previous worksheet in current workbook.t

Ctrl + Tab Move between two or more open Excel files

Alt+ = Create a formula to sum all of the above cells

Ctrl + ‘ Insert the value of the above cell into cell currently selected

Ctrl + Shift + !

Apply the Number format with two decimal places, thousands separator, and minus sign (-)

for negative values.

Ctrl+Shift+$ Apply the Currency format with two decimal places.

Ctrl+Shift+# Apply the Date format with the day, month, and year

Ctrl+Shift+% Apply the Percentage format with no decimal places

Ctrl+Shift+@ Apply the Time format with the hour and minute, and indicate A.M. or P.M.

Ctrl+y Redo last action (multiple levels)



Microsoft PowerPoint

The application software that can create professional slides is called Presentation Graphics software.

Operation-

PowerPoint presentation consists of a number of individual pages or slides.

Slides may contain text, graphics, movies or other objects.

Powerpoint facilitates the use of consistent style using templates.

Presentation can be printed or displayed live on a computer and navigated through at the command

of presenter.

Components of slides-

Title- A descriptive heading to identify a slide.

Subtitle- A brief message or description of the slide.

Drawing Objects-Drawing objecys include Autoshape, curves, lines, word art etc.

Clipart and pictures- Pictures and graphics are available in MS office suite.

Slide- It shows slide and its contents.

Slide sorter- It displays the entire set of slides on screen, so that you can check the order and

completeness of the presentation

Slide show- It displays the presentation of slide at a time in sequence

Animations and Transitions- Transitions are the special effect that introduce a slide in a slide show.

Animations are special sound or visual effects that can be added to the text

Microsoft PowerPoint Shortcut keys

Shortcut keys Description

Ctrl + A Select all items on the page

Ctrl + C Copy

Ctrl + P Opens print dialog Box

Ctrl + S Save

Ctrl + V Paste



Ctrl + X Cut

Ctrl + Z Undo last change

F5 View slide show

Shift + Ctrl + Home Select all text from the cursor to the start of the active text box

Shift + Ctrl + End Selects all text from the cursor to the end of the active text box

Spacebar or Mouse Click Move to next slide

S Stop the sho. Press S again to restart

Esc Ends the slide show

Ctrl + A Select al items on the page

Ctrl + B Applies the Bold to the selected text

Ctrl + D Duplicates the selected object

Ctrl + F Opens the Find dialog box

Ctrl + G Opens the Grids and Guides dialog box

Ctrl + H Opens the Replace dialog box

Ctrl + I Applies Italics to the selected text

Ctrl + M Inserts a new slide

Ctrl + N Opens a blank new presentation

Ctrl + O Opens the open dialog box

Ctrl + T Opens font dialog box

Ctrl + U Applies Underlining to the selected text

Ctrl + V Paste

Ctrl + W Closes the presentation

Ctrl + Y Repeats the last command entered

Home Moves cursor to the beginning of current line of text

End Moves cursor to the end of current line of text

Ctrl + Home Moves cursor to the beginning of presentation

Ctrl + End Moves cursor to the end of the presentation

Page Up Moves to previous slide

F7 Spell check



DBMS-

DBMS stands for Data Base Management System.

A database is a collection of data of a particular type.

A DBMS is well organized collection of data, instead of unsorted collection of files.

Data in the database is stored in tables.

An table is a row and column arrangement of information.

A DBMS is a collection of interrelated data and a set of programs to retrieve data from the

database.

RDBMS-

RDBMS stands for Relational Database Management systems.

A RDBMS is a multi table database where the tables in the database have to be related for

storing or retrieving data.

A RDBMS is used to create and maintain relational databases.

Components of Table-

Each table in a database has a unique name that identifies it from other contents.

A table is also called a relation.

The data in a table is organized under various categories.

Each category which is arranged vertically is called a column.

A column is referred to as a field.

Data organized horizontally is labelled as a row.



Computer Virus

A computer virus is a malware program which when executed, replicates itself into computer

programs, data files, or the boot sector of the hard drive. The affected areas by a virus are said to be

"infected".

A Virus harms the computer by using hard disk space or CPU time. Viruses also access the private

information of the user, corrupts data, spamming their contacts, or logging their keystrokes.

Not all viruses attempt to hide themselves.

In simple words, viruses are self-replicating computer programs which install themselves without the

user's knowledge.

Types of Virus-

1. Macro Virus- Macro virus harms the documents which use macros such as word processing and

excel spreadsheet documents. A macro virus is written in macro language.

2. Companion Virus- A virus that creates a new file with same existing filename.

3. Virus hoax- A computer virus hoax is a message, can be a false e-mail warning the recipients to

forward it to everyone they know.

4. Computer prank- It is a prank related to either the software or the hardware of computers.

5. WORM- A computer worm is a computer program that replicates itself in order to spread to other

computers. It mostly uses a computer network to spread itself. Unlike a computer virus, it does not

need to attach itself to an existing program.

6. Trojan horse- A Trojan horse is a generally non-self-replicating type of code which when executed,

causes loss or theft of data, and possible system harm.

Some of the famous computer virus-

1. Creeper-1971

2. Elk cloner-1982

3. The Morris Internet worm-1988

4. Melissa-1990

5. I Love You-2000

6. Code red-2001

7. Nimade-2001

8. SQL slammer-2003

9. Blaster-2003

10. Sasser-2004

Anti-Virus Software- Antivirus software is a computer software used to prevent, detect and remove

malicious software from computer. It is also known as Antivirus and anti-malware.



Antivirus software detects and removes computer viruses from the system. Antivirus software also

provides protection from other computer threats as there is rapid increase of other kinds of

malwares. Now days, an antivirus protects computer from malicious Browser Helper Objects (BHOs),

browser hijackers, ransomware, keyloggers, backdoors, rootkits, trojan horses, worms, malicious

LSPs, dialers, fraudtools, adware and spyware.

Antivirus software uses two techniques to accomplish its task-

Scanning files to find known viruses matching definitions.

Identifying any doubtful behaviour from any computer program that might infect the

computer.

Other Security Threats-

Phishing- Phishing is an attempt to acquire sensitive information such as usernames,

passwords, and credit card details by masquerading as a trustworthy entity in an electronic

communication.

Spam- Spamming is sending unsolicited messages, especially advertising, as well as sending

bulk messages on the same site or through an e-mail.

Malware- Malware disrupts computer operation, gather sensitive information, or gain access

to private computer systems without the user’s knowledge.

Adware-It is a software package which automatically starts advertisement.

Spyware- Spyware is software that gathers information about a person or organization

without their knowledge and may send such information to another entity without the

user’s knowledge.

Firewall- A firewall is a network security system which controls the incoming and outgoing

network traffic based on a set of rules. A firewall establishes an obstacle between a trusted,

secure internal network and another network. Firewalls exist both as a software solution

and as a hardware appliance.



Networking and Internet-

A network is a group of two or more computer systems connected together. The communication

between two or more computer systems connected together is called computer networking.

There are many types of computer networks, including: local-area networks (LANs) , MANs, WANs.

1. LAN(Local Area Network)- The local area network is designed to operate over a small area such as an office, building or

groups of building.

A LAN connects network devices over a short distance.

LANs are easy to design and troubleshoot.

In LAN, all terminals are connected to a main computer called server.

LAN network is owned and managed by a single person or an organization.

LAN machines are connected by a single cable.

Types of LAN-

Star LAN

In star LAN, all the stations are connected to a single computer.

The information after passing through its central station proceeds to its final destination.

If one node fails, the system connectivity is not affected.

Ring LAN

Point-to-point link is used to connect the cables.

There is no central station, so the data passes through its adjacent nodes to reach its final

destination.

If there is failure in a single node, the whole connectivity suffers as data passes through each

node to reach its destination.

Bus LAN

There is a single communication line.

There is no repeater.

Fault diagnosis is difficult.

2. MAN (Metropolitan Area Network) MAN is bigger version of LAN , it is designed for a city or town.

It connects an area larger than LAN but smaller than WAN.



A MAN is owned and operated by a private company or it may be wholly operated by a

private company.

We can share hardware and software resources over MAN.

A cable network is an example of MAN.

3.WAN(WIDE AREA NETWORK):

WAN is used to connect widely separated areas.

The communication between different users of WAN is established by a telephone lines or

satellite links.

WAN is not owned by any one organization but it owned by collective or distributed

ownership and management.

Types of WAN

Public Networks

The Networks owned and runned by telecommunication authorities and are made available

to individual user or organization.

Example-PSTN,PSDN,VAN,ISDN

Public Switched Telephone network (PSTN)

It is designed for telephone network which requires modem for telecommunication.

It is used for FAX machine also.

Low speed transmission, Analog transmission, easy access, it covers almost every place are

features of PSTN.

Public Service digital network(PSDN)

PSDN connects public and private mail system to have electronic mail services with other

firms.

High reliability, high quality communication, cost effective usage is the features of PSDN.

Value Added network(VAN)

It provides electronic data interchange facility

The network is rent out to subscribers.

Exchange of information like sale purchase, invoices is done.

Integrated Service digital network(ISDN)

ISDN is used for voice, video and data services.

It uses digital transmission.

It combines both packet and circuit switching.

Private Network-

Private network provides services at various locations using private circuits.



It uses modems and multiplexes.

Large volume of data is carried at very high speed transmission.

Network Toplogies-

Topology refers to the layout of connected devices. There are two possible ways to connect the

devices-

1. Point to point connection

2. Multipoint connection

The meaning of topology indicated that the way in which a network is laid out. Two or more devices

connected to a link, two or more links form a topology.

Network topologies are categorized into the following basic types:

Bus Topology

Ring Topology

Star Topology

Tree Topology

Mesh Topology

More complex networks can be built as hybrids of two or more of the above basic topologies.

Bus Topology

The bus topology is usually used when a network is small, simple.

In a bus topology, there is a single cable with no active electronics to amplify the signal. In bus

topology, when one computer sends the signal, all the computers in the network receives the

information.

The speed of bus topology is slow as only one computer can send the message at one time. A

computer must wait until the bus is free. The bus topology requires proper termination at both the

ends.

Ring Topology

In a ring topology, each computer is connected to the next computer, with the last one connected to

the first one. The messages flow around the ring in one direction. There is no termination because

there is no end to the ring. Some ring networks do token passing. A short message token is passed

around the ring until the computer wishes to send the information to another computer.

Every device in a ring topology has exactly two neighbors for communication purposes. All messages

travel through a ring in the same direction (which can either be "clockwise" or "counterclockwise").

A failure in any cable or device breaks the loop and can take down the entire network.



Star Topology

In star topology, there is one central computer to which all the other computers in the network are

connected. All the cables run from the computers to a central location where they are connected to

a device called hub.

Each computer on a star network communicates with a central hub that resends the message either

to all the computers or only to the destination computer. An active hub generates the signal aand

sends it to all computers connected to it. This type of Hub is called multiport repeater.

The network in our homes uses the star topology. A star network connects with a central connection

point called a "hub node" that may be a network hub , switch or router . Devices typically connect to

the hub with Unshielded Twisted Pair (UTP) Ethernet.

A star network generally requires more cable as compared to the bus topology. But if there is a

failure in any star network cable will only take down one computer's network access and not the

entire LAN.

Tree Topology

A tree topology is the variation of a star. As in stars, nodes in a tree are linked to a central hub that

controls the traffic to the network.

Not every computer plugs into the central hub. But most of them are connected to a secondary hub

which in turn is connected to a central hub. The central hub is an active hub which contains

repeater. The repeater amplifies the signal and increases the distance a signal can travel

Only hub devices connect directly to the tree bus, and each hub functions as the root of a tree of

devices. This bus/star hybrid can be approached for future expandability of the network much better

than a bus or a star alone.

Mesh Topology

In mesh topology, every device has a dedicated point-to-point link to every other device. The

dedicated link carries traffic only between two devices.

The messages sent on a mesh network can follow any of several possible paths from source to

destination. Some WANs , most notably the Internet, employ mesh routing.

A mesh network in which every device connects to every other is called a full mesh.



Internet

The Network of interconnected network which enable users to share information is called internet.

A computer that has an access to an Internet can collect information from a vast array of servers

available.

Most of the information on the internet is inter-linked with the hyper text documents and other

resources from which a user can access it.

With the help of web browser a user typically sends and receives information. Other interfaces like

e-mail, online chat, file transfer and file sharing can also be used to share information.

The movement of information on the internet is managed by interconnected computer networks

that share information by a standard TCP/IP protocol.

Internet is network of networks connected together to share information all over the world.

Internet consists of millions of private ,public, academic, business and government networks that are

connected by copper wires, fibre optic cables, wireless connections.

Internet is a way in which computers communicates and shares information.

It is worldwide collection of networks.

Internet Services

E-mail-Electronic mail is the most popular network services. The internet enables user to

exchange data and communicate with the help of electronic mail. Simple mail transfer

protocol (SMTP) protocol is a protocol used for sending an email and for receiving it is Post

office Protocol (POP3).

Chat

Chat is a form of exchanging messages by typing. Online chat refers to any kind of

communication over the Internet that allows a real-time transmission of text messages from

sender to receiver. Chat messages are generally short in order to enable other participants

to respond quickly.

Video Conferencing

Video conferencing allows users to exchange video information over the internet. It includes

an audio teleconference facility. Videoconferencing (VC) is the conduct of a videoconference

by a set of telecommunication technologies which allow two or more users to communicate

with each other by simultaneous two-way video and audio transmissions.



TCP/IP (Transmission Control Protocol) - TCP/IP is the computer networking

model and set of communications protocols used on the Internet and other computer

networks. TCP/IP is most important protocols.

The Transmission Control Protocol (TCP) and the Internet Protocol (IP), were the first

networking protocols defined in this standard. TCP/IP provides end-to-end connectivity

specifying how data should be packetized, addressed, transmitted, routed and received at

the destination.

PPP (Point-to-Point Protocol) - PPP is a data link protocol which is used to establish a

connection between two nodes. It can provide connection authentication, transmission

encryption, and compression.

PPP is used over many types of physical networks which include serial cable, phone line,

trunk line, cellular telephone, specialized radio links, and fiber optic. PPP is also used over

Internet access connections. Internet service providers (ISPs) have used PPP for customer

dial-up access to the Internet, since IP packets cannot be transmitted over a modem line on

their own, without some data link protocol.

WWW- The World Wide Web (WWW, W3) is a system of interlinked hypertext documents

which are accessed with the help of Internet. It is commonly known as the Web. The pages

on the internet are called web pages which are accessed with the help of a software

application known as web browser. Web pages may contain text, images, videos, and other

multimedia components, as well as web navigation features consisting of hyperlinks.

Gopher- The Gopher protocol is a TCP/IP application layer protocol for distributing,

searching, and retrieving documents over the Internet. The Gopher protocol was strongly

designed as an alternative to the World Wide Web in its early stages. But then HTTP took

over as a dominant protocol.

Wais- Wide Area Information Servers or WAIS is a client–server text searching system that

uses Information Retrieval Service Definition and Protocol Specifications for Library

Applications to search index databases on remote computers.

Mosaic- Mosaic is the first graphical web browser. Mosaic is a web browser due to which

the World Wide Web became popular. It was a client for earlier protocols such as FTP,

NNTP, and gopher. Mosaic was named for its support of multiple internet protocols. Mosaic

was the first browser to display images with text instead of displaying images in a separate

window.



Archie- Archie is a tool for indexing FTP archives which allows people to find specific files.

It is considered to be the first Internet search engine. It searches its database and then gives

information about the files.

Hypertext- Hypertext is text with references (hyperlinks) to other text which the user

can immediately access. The hypertext pages are interconnected by hyperlinks. Hypertext is

the underlying concept defining the structure of the World Wide Web, with pages often

written in the Hypertext Markup Language (HTML). It enables an easy-to-use and flexible

connection and sharing of information over the Internet.

Wireless LAN- A wireless local area network (WLAN) is a wireless computer network

which connects two or more devices using a wireless distribution method within a limited

area such as a home, school, computer laboratory, or office building. The users have the

ability to roam around, still be connected to the network.

ISP(Internet Service Provider) An ISP is an organization that offers users to access

to the internet and related service. Mostly ISPs are telephone companies. They provide

services such as hosting, domain name registration, dial-up.

FTP (File transfer Protocol)- FTP is used to exchange files over the internet which

supports TCP/IP protocol. In FTP transfer, there are two computers involved-one server and

other one client.

Internet Protocol Suite- IPS is the set of protocols that helps internet and

commercial networks to run.It is also called TCP/IP protocol suite.TCP/IP are the most

important protocols for transmitting data over the Internet. They are the two most

important protocols- Transmission control protocol (TCP) and Internet Protocol (IP)

NSP(Network Sevice Provider)- A NSP is an organizatiomthat sells bandwidth or

network by providing direct access to the internet. They are reffered to as Internet

providers.

Network service providers consists of telecommunications companies, data carriers,

wireless communications providers, Internet service providers and other operators offering

high speed internet.

Web Server- A web server is a program that uses client/server model and Hypertext

transfer protocol. Every website on the internet contains a website which must have a web

server program. Apache and Microsoft’s Internet Information Server (IIS) are the examples

of two leading web server.



Client Server- Client server separates client from the server. The client software send

requests to a server.eg if you are visiting a website then your computer and web browser

will be considered a client and the server that hold that website would be considered as

server.

Proxy Server- A proxy server is a computer that allows a computer network to allow an

indirect network connections to other network services. A proxy server can also serve as a

firewall. A user connects to proxy server than requests a connection file which is available

on another server. The proxy server provides the resource by connecting to the specific

server.

Website- A website is a collection of web pages on the worldwide web.

Static website- A static website is one that has content which does not change frequently

and is manually updated by some person.

Dynamic website- A dynamic website is the website on which the content changes

frequently. When the server receives request, the page is automatically generated by

software in response to the request.

Web Page- A webpage is usually written in HTML/XHTML format with hyperlinks

enabling navigation from one page to another page. The extensions of webpage can vary

such as .htm, .html, .php etc. A web page is displayed with the help of web browser like

Opera, Mozilla Firefox, and Chrome. The webpage can contain-

Text

Graphics- GIF, JPEG, PNG formats

Audio-MIDI or WAV formats

Hyperlinks

Macromedia Flash

Dynamic Webpage- Dynamic web pages contain dynamic content like images, text

etc. This can change/ move without web page being uploaded.

Home Page- Home page is the first page of the website. It is also called the main page of

the website.

Uniform Resource Locator-A uniform resource locator is another name for website

address. A uniform resource locator is used with HTTP, is a specific character string that

constitutes a reference to a resource. Most web browsers display the URL of a web page

above the page in an address bar. E.g. The URL of Google search engine is www.google.com



WAP- Wireless Application Protocol (WAP) is a technical standard for accessing

information over a mobile wireless network. A WAP browser is a web browser for mobile

devices such as mobile phones that uses the protocol.

Web Addresses- A Web address, or domain name, is an address where a website can

be found. It's how you'll express yourself through email or your website and it's what

customers think of when trying to find you.



Applications of Computer-

Business

A computer can perform high speed calculation, is more accurate, reliable, or versatile which made

it an important part in all business organisations.

Computer is used in business organisations for:

Payroll calculations

Budgeting

Sales analysis

Financial forecasting

Managing employees database

Maintenance of stocks etc.

Banking

Banking is totally dependent on computer.

Banks provide following facilities:

Almost all the banks today provides Internet Banking

Insurance

Insurance companies keep the records up-to-date with the help of computers. Computer is widely

used by the insurance companies, finance houses and stock broking firms.Insurance companies are

maintaining a database of all clients with information showing

Education

The computer provides a lot of facilities in the education system.

The computer provides a tool in the education system known as CBE (Computer Based Education).

CBE includes control, delivery, and evaluation of learning.

The graph of number of computer students studying computers has rapidly increased.

Marketing

In marketing, uses of computer are following:

Advertising -

At Home Shopping

Health Care



Computers have become important part in hospitals, labs, and dispensaries. The computers are

being used in hospitals to keep the record of patients and medicines. It is also used in scanning and

diagnosing different diseases. ECG, EEG, Ultrasounds and CT Scans etc., are also done by

computerised machines.

Some major fields of health care in which computers are used are:

Diagnostic System

Lab-diagnostic System

Patient Monitoring System

Pharma Information

Surgery

Engineering Design

Computers are widely used in Engineering purpose.

One of major areas is CAD (Computer aided design)

Structural Engineering

Industrial Engineering

Architectural

Military

Computers are majorly used in defence. Modern tanks, missiles, weapons etc. Military is employing

computerised control systems. Some military areas where a computer has been used are:

Missile Control

Military Communication

Military Operation and Planning

Smart Weapons

Communication

Communication means sending a message which can be in the form of text, video or an image. Some

main areas in this category are:

E-mail

Chatting

Usenet

FTP

Telnet

Video-conferencing

Government



Computers play an important role in government offices. Almost every government office is

equipped with a computer. It can be used in the following areas-

Budgets

Income tax department

Computerization of voters lists

Computerization of driving licensing system

Computerization of PAN card

Weather forecasting

Computer Terminologies-

Active Server Pages (ASP): A standard for scripting server side web pages.

Active Cell: The cell in MS Excel with dark boundary is called the active cell.

Analog: Describing a system particularly an electronic device that uses a continuous physical

quantity to represent information.

API (Application Programming Interface): It is a set of tools for building software applications. A

good API makes it easier to develop a program by providing all the building blocks .A programmes

then put the building blocks together

Back-up File: A copy of all the files created as a safety precaution in case any harm occurs to the

original.

BASIC (Beginner’s All-Purpose Symbolic Instruction Code): An easy to use High Level language

which is now replaced by improved version of Microsoft Visual Basic.

Blind Carbon Copy (BCC): In e-mail, a copy of message that is sent to one or more persons without

the knowledge of other recipients.

Bit: Basic unit of computer which has two values ‘0’ and ‘1’.

Byte: One byte is a collection of 8 bits.

Basic Input /Output System (BIOS): It handles the start up operations and low-level control for

hardware .Also known as ROM BIOS.

Boot Loader: It reads the main portion of the operating system form secondary memory.

Boot: An initiating automatic routine that is read into RAM when a computer is first turned on. This

provides the necessary environment for subsequent loading of all or part of the operating system,

software application etc. It prepares the computer for use. The process of starting a computer is

called boot and restarting is called warm boot.



Bootstrap Protocol (BOOTP): It a computer networking protocol that which is used by a client to

obtain an IP address form a server. It is used to establish a connection during a computer’s initial

boot up during the Bootstrap process.

Bandwidth: It tells about the data transmission rate of a network or internet connection. Bandwidth

is used to calculate the amount of time that is required to send a data over a specific connection.

Bus: A bus is a communication system that allows the data to be passed back and forth inside a

computer or between the computers.

Bug: An error in a software program is called a bug.

Cache: A cache is a temporary storage area where frequently accessed data can be stored for rapid

access. It acts as a buffer between CPU and memory.

Clock speed: A rate at which a processor can complete a processing cycle is called clock speed.

.Com: .Com (Commercial) is a top level domain name used by businesses, although individual

register.

CGI (Common Gateway Interface): A standard method used to generate dynamic content on web

pages and web applications.

Cookie: Cookie is user data that is stored in a user’s browser to notify the application server of the

user’s previous activity regarding that application

Copyright: It means the material and information are the personal property of the owner or

producer.

Counter feiting: It is the process of making and distributing illegal copies of software packages.

DBMS: It stands for Data Base Management System. It is a software package to manage database.

Data processing: It is process to get meaningful information from data.

DHTML (Dynamic Hyper Text Markup Language): It is used to create dynamic content on web

pages.

Digital Signature: It is a cryptographic scheme to preserve the originality of digital documents

Dots per inch (dpi): It measures the resolution that states the number of dots that the device can

print, scan or display in a linear inch.

DNS (Domain Name System): Is a system that distributes unique name to internet resources that

identifies those resources across internet network

ERP (Enterprise Resource Planning): It is management software used in enterprises to collect, store

and manage their resources



Ethernet: It is the most popular type of LAN, in which communication through radio frequency

signals is carried by a co-axial cable.

Ethernet Card: A network adapter that enables a computer to connect to an Ethernet.

Ethics: Ethics are rules and belief.

FTP (File Transfer Protocol): A client/ server protocol for exchanging files with a host computer.

FAX: Facsimile- used to send printed pages between two locations using the telephone line.

Firewall: They provide some protection form online intrusion but they don’t protect against some

unpatched vulnerabilities in the application packages.

File: A file is a collection of related records.

.GOV: It is a government domain name denoting government office or agency.

.GIF (Graphic Interchange Format): It is a file extension which is used on the internet to encode and

Exchange graphics.

GUI (Graphical User Interface): A computer program that enables a person to communicate with a

computer through the use of symbols, visual metaphors and pointing devices.

Gateway: Gateway is server that routes between different networks

Google: Google is a search engine.

Hyperlink: A highlighted word in a text or picture in a document or web page which can be used to

go to another page by clicking it with a mouse.

Hard Disk: A hard disk is a secondary memory which can store anywhere from 10MBs to several GBs.

Hub: Hub connects multiple ethernet devices together into a single network

Hacker: A hacker is a person who breaks into a computer system to get access the information

stored there.

HTML: HTML (Hyper Text Markup Language) is a markup language used to create web pages.

HTTP: Hyper text transfer protocol is used often to transfer information form WWW servers to

browsers.

ICMP (Internet Control Message Protocol): Protocol to send error messages.

IMAP (Internet Message Access Protocol): Protocol for email access and management.

IP (Internet Protocol): It is a standard that describes that how an internet connected computer

break down data into packets for transmission across the network and how these packets should be

addressed so that they arrive at their destination.



IP Address: It is a 32- bit binary number that uniquely identifies the location of a particular user on

the internet.

Internet Service Provider (ISP): An organization that provides the services of Internet to the

Subscriber based customers.

Intranet: It is a private network that is contained with an enterprise.

JPEG: Joint Photographic Experts Group is a graphics format that is ideal for complex pictures

/graphics.

Kb: Kilobit

LAN: A LAN (Local Area Network) connects network devices over a relatively short distance.

LCD: Liquid Crystal Display. It Used in Laptop computers small battery power electronic devices.

LED: LED stands for Light Emitting Diode. A small electronic device made from semiconductor

materials.

LINUX: It is a UNIX like Operating System with graphical user interface

Mainframe: Mainframe is a very large in size and an expensive computer capable of supporting

hundreds, or even thousands, of users simultaneously. Mainframe executes many programs

concurrently. Mainframes support many simultaneous programs execution

MIME: Multipurpose Internet Mail Extension. It specifies that how the multimedia files can be

transferred through the E-mail programs and web browsers.

MIPS: Million Instructions Per Second. It is a method of measuring the rate at which the computer

executes microprocessor instructions.

MODEM: A modem is the device needed to translate between the analog phone line and the digital

computer. Its function is modulated /demodulates the digital signal.

MIDI: Musical Instrument Digital Interface. It is a standard communication protocol for the exchange

of information between computers and musical synthesisers.

Malware: Malware is software which is designed specifically to damage a computer system.

Morphing: It is used in computer animation in which an image change smoothly from one image to

another.

M-Commerce: It is used for the commercial transactions that are done by Mobile Phones.

Mozilla: Mozilla is a web browser

Multitasking: Multitasking is the method with multiple tasks processes sharing common processing

resources such as CPU



MAC OS: It is an Operating System used in Macintosh Computer developed by Apple.

NIBBLE: A group of 4-bits.

Network: A group of two or more computers that are linked together.

NIC (Network Interface Card): It is a computer component which is used to connect a computer to a

computer network.

ODBC: Open Database Connectivity. It is a standard that enables applications to communicate with

variety of database applications.

OOP: Object Oriented Programming

OS: Operating system provides an interface between the human user and the computer hardware

PDF: Portable Document Format. It is file extension created by Adobe systems.

POP3: Post Office Protocol. An internet e-mail standard that specifies how an internet connected

communicates as mail handling agent.

POST: Power on Self-Test. It is internal testing which is performed when the computer is started or

reset.

Piracy: It is the legal reproduction and distribution of software application

Primary Key: It is a field with unique value for each record

Primary Memory: It temporarily/permanently holds the data received form input/output device. It

holds the data being processed and intermediate results being generated.

Port: a physical docking point using which an external device can be connected to the computer.

PPP: Point to Point Protocol.

Protocol: It is set of riled or standards designed so that computers can exchange information with a

minimum error

Peripherals: A device that connects to and works with the computer eg Mouse, Keyboard.

Password: A sequence of characters which is used to check the authenticity of the user.

Query: It is used to extract information from a database.

RAM: A RAM constitutes the internal memory of the CPU for storing data, program and program

result. It is read/write memory. It is called random access memory (RAM).

RDBMS: Relational Database Management System. A database management system that is based on

the relational model.



Record: It is the collection of the related fields.

ROM (Read only memory): The data store in this cannot be changes and it’s a non-volatile memory.

Secondary Memory: used to store data and information permanently .Data is stored permanently

even if power is switched off.

Software: It is set of programs that guides the hardware through its job

System Software: System software refers to all the programs, which make the computer work and is

based on controlling the internal computer operations.

SMTP (Simple Mail Transfer Protocol): An internet Protocol that governs the transmission of e-mail

over computer networks.

Scanner: Scanner is an input device, which works more like a photocopy machine. It is used when

some information is available on a paper and it is to be transferred to the hard disc of the computer

for further manipulation.

Spoof: It is to deceive or to fake, especially with the intension of gaining unauthorised access to

computer resources.

Spam: An irrelevant and unsolicited message sent over the internet.

SPOOL: Simultaneous peripheral Operations on Line

Search Engine: It is program which is used to search a document with a specific keyword when use

will enter its keyword it returns a list of matching documents.

Sorting: It is arranging of data in order

Trash: A folder in the e-mail which kept all the deleted mails.

Tag: It is a part of HTML .It determines the way, the browser display text in web page.

Topology: A network topology is the physical layout of the networks in which all the devices are

connected among themselves.

Telnet: Telnet is network protocol with the help of which a user one computer can log into another

computer that is the part of the same network.

Trojan horse: A programme that appears to perform a valid function but has some hidden

instructions in its code that can cause server damage to the system on which the programme runs.

UPS: Uninterruptable Power Supply. A battery system that can supply continuous power to a

computer in the event of a power failure for some times.

URL: Uniform Resource Locator. It is the unique address for a file that is accessible over the internet.



USB: Universal Serial Bus enables the communication between the computer and the peripheral

devices

UNIX: It is a powerful multiuser operating system. It uses command text in Web Page.

VAN (Value Added Network): A public data network that provides value added services for

corporate customers including end-to-end dedicated lines with guaranteed security.

Virus: A virus is a computer program that can copy itself and infect a computer. A virus can spread

from one computer to another computer when its host is taken to the target computer.

W3 (WORLD WIDE WEB): It is a system of interlinked hypertext documents accused via internet.

WAN (Wide area Network): A WAN is a geographically dispersed collection of LANs.

WORM (Write Once Read many): It is a storage device to store data in which once the information is

written it cannot be erased or modified.

Web Browser: It is a software application for retrieving, presenting and traversing information

resources on the World Wide Web

Wi-Fi: It stands for Wireless- fidelity. It is used by the most personal computer operating systems,

many video game consoles, laptops, printers and other peripherals.

XML: Extensible Markup Language.

.ZIP: Compressed File (File name Extension.)



COMPUTER ABBREVIATIONS

A

• ALU : Arithmetic Logic Language • ARP: Address Resolution Protocol • AI: Artificial Intelligence • ALGOL: Algorithmic Language • ASCII: American Standard Code for Information and Interchange • ATDML : Asynchronous Time Division Multiplexing

B

• BASIC: Beginner’s All-purpose Symbolic Instruction Code • BIOS: Basic Input Output System • BCC: Blind Carbon Copy • BINAC: Binary Automatic Computer • Bin: Binary • Bit: Binary Digit

C

• CAD: Computer Aided Design • CAM: Computer Aided Manufacturing • CC: Carbon Copy • CD: Compact Disc • CD-ROM: Compact Disc Read Only Memory • CDRW: Compact Disc Rewritable • CRT: Cathode Ray Tube • CDMA: Code Division Multiple Access • CDR: Compact Disc Recordable • CDR/W: Compact Disk Read/Write • COBOL: Common Business Oriented Language • CPU: Central Processing Unit

D

• DBA: Data Base Administrator • DBMS: Data Base Management System • DVDROM: DVD Read Only Memory • DVDRW: DVD Rewritable • DVR: Digital Video Recorder • DNS: Domain Name System • DOS: Disk Operating System



• DOS : Disk Operating System • DMA : Direct Memory Access • DVD: Digital Video Disc/Digital Versatile Disc • DVDR: DVD Recordable • DPI: Dots per Inch • DRAM: Dynamic Random Access Memory

E

• EBCDIC: Extended Binary Coded Decimal Interchange Code • E-Commerce: Electronic Commerce • EDP: Electronic Data Processing • ENIAC: Electronic Numerical Integrator and Computer • EOF: End Of File • EPROM: Erasable Programmable Read Only Memory • EXE: Executable • EEPROM: Electronically Erasable Programmable Read Only Memory • E-Mail: Electronic Mail

F

• FAX: Far Away Xerox/ facsimile • FDC: Floppy Disk Controller • FDD: Floppy Disk Drive • FDMA : Frequency Division Multiplexing Access • FLOPS: Floating Operations per Second • FORTRAN: Formula Translation • FS: File System • FTP: File Transfer Protocol

G

• GB: Gigabit • GB: Gigabyte • GIF: Graphics Interchange Format • GSM: Global System for Mobile Communication • GUI : Graphical User Interface

H

• HDD: Hard Disk Drive • HDTV : High Definition Television • HTML: Hyper Text Mark-up Language • HTTP: Hyper Text Transfer Protocol • HLL: High Level Language

I

• IC: Integrated Circuit • IM: Instant Message



• IMAP: Internet Message Access Protocol • ISP: Internet Service Provider • INSP : Inter Name Server Protocol

J

• JPEG: Joint Photographic Experts Group

K

• Kb: Kilobit • KB: Kilobyte • KHz: Kilohertz • Kbps: Kilobit Per Second

L

• LAN: Local Area Network • LCD: Liquid Crystal Display • LDU: Liquid Display Unit • LED: Light Emitting Diode • LIS: Large Scale Integration • LISP: List Processing • LPI: Lines per Inch • LLL: Low Level Language

M

• MAN: Metropolitan Area Network • MAP : Mobile Application Port • MAPI: Mail Application Programming Interface • Mb: Megabit • MB: Megabyte • Mbps : Mega bits per second • MCB : Memory Control Block • MCR : Magnetic Card Reader • MMS: Multimedia Message Service • MICR: Magnetic Ink Character reader • MIDI : Musical Instrument Digital Interface • MIME : Multipurpose Internet Mail Extension • MIPS: Million Instructions per Second • MOPS: Millions of Operations per Second • MPU: Micro Processor Unit • MPEG: Moving Picture Experts Group

N

• NIC: Network Interface Card • NETBIOS : Network Adapter Basic Input Output System • NFAR : Network File Access Routine



• NOS: Network Operating System • NSP : Network Services Protocol • NVRAM: Non- Volatile Random Access Memory

O

• OAIS : Open Archival Information System • OLTP : Online Transaction Processing • OMR: Optical Mark Reader • OMAP : Open Multimedia Application Platform • OOP: Object Oriented Programming • OSS: Open Source Software

P

• PAP : Password Authentication Protocol • PC: Personal Computer • PCM : Pulse Code Modulation • PDA: Personal Digital Assistant • PDN : Public Data Network • PDP : Packet Data Protocol • PDF: Portable Document Format • PING: Packet Internet Gopher • POS: Point Of Sale • POST: Power on Self Test • PNG: Portable Network Graphics • PPM: Pages per Minute • PPP: Point-to-Point Protocol • PIN : Personal Identification Number • PRISM : Parallel Reduced Instruction Set Multiprocessing • PROM: Programmable Read Only Memory • PSDN : Packet-Switched Data Network • PSTN: Public Switched Telephone Network

R

• RAM: Random Access Memory • RARP : Reverse Address Resolution Protocol • RDBMS: Relational Data Base Management System • RIP: Routing Information Protocol • RTF: Rich Text Format • RTCP : Real Time Control Protocol

S

• SDRAM : Synchronous Dynamic Random Access Memory • SGML : Standard Generalized Markup Language • SIM: Subscriber Identification Module • SLIP : Serial Line Internet Protocol • SMTP: Simple Mail Transfer Protocol



• SNA : Sub Network Access Protocol • SNMP: Simple Network Management Protocol • SQL: Structured Query Language • SRAM: Synchronous Random Access Memory • SSML : Security Service Markup Language • STP : Spanning Tree Protocol • SWAP : Superior Wireless Application

T

• TB: Tera Bytes • TCP/IP: Transmission Control Protocol /Internet Protocol • TDMA: Time Division Multiple Access

U

• UDMA : Ultra Direct Memory Access • UIML : User Interface Markup Language • ULSI: Ultra Large Scale Integration • UNIVAC: Universal Automatic Computer • UPS: Uninterrupted Power Supply • URI: Uniform Resource Identifier • USB: Universal Serial Bus

V

• VAR: Variable • VDU: Visual Display Unit • VOIP: Voice Over Internet Protocol • VGA: Video Graphics Array • VLSI: Very Large Scale Integrated • VRAM : Volatile Random Access Memory • VRML : Virtual Reality Modelling Language • VSAM : Virtual Storage Access Method

W

• Wi-Fi: Wireless Fidelity • WLAN: Wireless Local Area Network • WPA: Wi-Fi Protected Access • WWW: World Wide Web • WAN: Wide Area Network • WCCP : Web Cache Control Protocol • WORM: Write Once Read Many • WML : Wireless Markup Language • WSDL : Web Services Description Language



X

• XHTML: eXtensible Hyper text Markup Language • XML: eXtensible Markup language

Z

• ZB: Zeta Byte • ZIP : Zone Information Protocol

Some Important programming languages-

1. FORTRAN- FORTRAN was derived from Formula Translating System. It is a general-purpose,

important programming language. This language is appropriate for the numeric

computation and scientific computing. This language was originally developed by IBM in the

1950s for scientific and engineering applications.

FORTRAN dominated the area of programming. It has been in continuous use for over half a

century. It is used in numerical weather prediction, finite element analysis, computational

fluid dynamics, computational physics and computational chemistry. It is one of the most

popular languages in the area of high-performance computing .

2. Cobol

COBOL is an acronym for common business-oriented language. It is a compiled English-like computer

programming language designed for business use. COBOL language is imperative, procedural and,

since 2002, object-oriented. COBOL is primarily used in business, finance, and administrative

systems for companies and governments.

COBOL is still widely used in applications of mainframe computers, such as large-scale batch and

transaction processing jobs. In modern time, the language is declining its popularity. Various COBOL

programmers are being migrated to new platforms, rewritten in modern languages or replaced with

software packages. Most programming in COBOL is now purely to maintain existing applications.

3. LISP

Lisp is a family of computer programming languages. Lisp is the second-oldest high-level

programming language which is widely used today. Like Fortran, Lisp has changed a great deal since

its early days, and a number of dialects have existed over its history.

Lisp was originally created as a practical mathematical notation for computer programs, influenced

by the notation of Alonzo Church's lambda calculus. It quickly became the preferred programming

language for artificial intelligence (AI) research. As one of the earliest programming languages, Lisp

evolved as many ideas in computer science, including tree data structures, automatic storage



management, dynamic typing, conditionals, higher-order functions, recursion, and the self-hosting

compiler.

4. Algol

ALGOL ( ALGOrithmic Language)-is a computer programming languages was originally developed in

the mid-1950s. It was the standard method for algorithm description used by the ACM in textbooks

and academic sources for more than thirty years. It was arguably the most successful of the four

high-level programming languages: Fortran, Lisp, and COBOL.

It was designed to avoid some problems with FORTRAN and eventually gave rise to many other

programming languages, including BCPL, B, Pascal, PL/I, Simula, and C. ALGOL was the first language

implementing nested function definitions with lexical scope. It was the first programming language

which gave serious attention to formal language definition

5. Pascal

Pascal is a procedural programming language which was designed in 1968–1969 and published in

1970 by Niklaus Wirth as a small and efficient language which was developed to encourage good

programming practices using structured programming and data structuring.

6. C

C is a general-purpose, imperative computer programming language. It supports structured

programming.

C was originally developed by Dennis Ritchie between 1969 and 1973 at AT&T Bell Labs. It was used

to (re-)implement the Unix operating system. It has since become one of the most widely used

programming languages of all time.

7. C++

C++ is a general-purpose programming language. It has object-oriented and generic programming

features.

It is designed with a bias toward system programming (e.g., for use in embedded systems or

operating system kernels), with performance, efficiency and flexibility of use as its design

requirements. C++ has also been found useful in many other contexts, including desktop

applications, servers, performance-critical applications, and entertainment software

8. Java-

Java is a general-purpose computer programming language that is concurrent, class-based, object-

oriented. Java applications are typically compiled to bytecode that can run on any Java virtual

machine (JVM) and is independent of computer architecture. Java is one of the most popular

programming languages in use, particularly for client-server web applications. Java was originally

developed by James Gosling at Sun Microsystems (which has since merged into Oracle Corporation)

and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives

much of its syntax from C and C++.



9. Perl

Perl is a family of high-level, general-purpose, interpreted, dynamic programming languages. The

languages in this family include Perl 5 and Perl 6.

Perl is also known as Practical Extraction and Reporting Language. Perl was originally developed by

Larry Wall in 1987 as a general-purpose Unix scripting language to make report processing easier.

Since then, it has undergone many changes and revisions.

10. Visual Basic

Visual Basic is a third-generation event-driven programming language and integrated development

environment (IDE) from Microsoft for its COM programming model first released in 1991. Microsoft

intended Visual Basic to be relatively easy to learn and use. Visual Basic was derived from BASIC and

enables the rapid application development (RAD) of graphical user interface (GUI) applications,

access to databases using Data Access Objects, Remote Data Objects, or ActiveX Data Objects, and

creation of ActiveX controls and objects.

A programmer can create an application using the components provided by the Visual Basic program

itself. Programs written in Visual Basic can also use the Windows API, which requires external

function declarations.

Types of programming language-

1. First generation programming language- A first-generation programming language (1GL) is a

machine-level programming language. There was no translator to compile or assemble the

first-generation language. The first-generation programming instructions were entered

through the front panelswitches of the computer system.

A first generation language (1GL) is a group of programming languages that are machine level

languages. The instructions were given through the front panel switches of these computers, directly

to the CPU. There was originally no compiler or assembler to process the instructions in 1GL.

The instructions in 1GL are made of binary numbers which is represented by 1s and 0s. Binary

numbers enables machine to understand but it makes it difficult to interpret and learn by the human

programmer.

The main advantage of programming in 1GL is that the code can run very fast and very efficiently,

precisely because the instructions are executed directly by the CPU. One of the main disadvantages

of programming in a low level language is that when an error occurs, the code is not as easy to fix.

2. Second generation programming language-

Second-generation programming languages have the following properties:-The code can be read and

written by a programmer. To run on a computer it must be converted into a machine readable form,

a process called assembly. Secondly, the language is specific to a particular processor family and

environment.



Second-generation languages are sometimes used in kernels and device drivers. But more widely,

they are used in extremely intensive processing such as games, video editing, graphic

manipulation/rendering.

3. Third generation programming language-

A third-generation programming language (3GL) is way to categorize high-level computer

programming languages. Second generation programming languages, like assembly

languages are machine-dependent. Third generation language are machine independent and

more programmer-friendly. 3GLs feature more abstraction that previous generations of

languages. Fortran, ALGOL, and COBOL are early examples 3GL.

C, C++, C#, Java, BASIC and Pascal, are also third-generation languages, although each of these

languages can be further subdivided into other categories Most 3GLs support structured

programming.

4. Fourth generation-

A fourth-generation programming language (4GL) is a computer programming language include

support for database management, report generation, mathematical optimization, GUI

development, or web development. Fourth-generation languages have often been compared to

domain-specific languages (DSLs). Some researchers state that 4GLs are a subset of DSLs.

5. Fifth generation-

A fifth generation programming language (5GL) is a programming language based on solving

problems using constraints given to the program, rather than using an algorithm written by a

programmer. Most constraint is on based and logic programming languages and some declarative

languages are fifth-generation languages.

Fifth-generation languages are designed to make the computer solve a given problem without the

programmer. Fifth-generation languages are used mainly in artificial intelligence research. Prolog,

OPS5, and Mercury are examples of fifth-generation languages.[citation needed]

These types of languages were also built upon Lisp, many originating on the Lisp machine, such as

ICAD. Then, there are many frame languages, such as KL-ONE.

Low level programming language-

A low-level programming language is a programming language that provides little or no abstraction

from a computer's instruction set architecture. A low level programming language refers to machine

code or assembly language.

Low-level languages can be converted to machine code without the help of a compiler or

interpreter. The code runs directly on the processor. A program written in a low-level language can

be made to run very quickly and takes very small memory. Low-level languages are simple, but are

considered difficult to use.

High level programming language-



A high-level programming language is a programming language with strong abstraction from the

details of the computer. It may use natural language elements, be easier to use, or may automate

significant areas of computing systems (e.g. memory management), making the process of

developing a program simpler and more understandable relative to a lower-level language.

High-level programming languages using a compiler were called autocodes. Examples of autocodes

are COBOL and Fortran.

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