Computer Concepts and Applications (FY B.Com) PDF

F.Y. B.Com. Computer Concepts and Applications (Computer Fundamentals) Submitted by Dr. Ranjit Patil Vice-Principal and HOD, Dr. D. Y. Patil ACS College, Pimpri Mr. Vilas Wani HOD, Mamasaheb Mohol College, Paud Road, Pune F.Y. B.Com. Computer Concepts and Applications 104(B) (Computer Fundamentals) Term - I Unit Topic No 1. Introduction to Computer Fundamentals Introduction to Computer Computer System Hardware Computer Memory Input and Output Devices Interaction between User and Computer Introduction to Free and Open Source Software Definition of Computer Virus, Types of Viruses, Use of Antivirus software 2. Basics of Operating System Definition of Operating System Objectives, types, and functions of Operating Systems Working with Windows Operating System: Introduction, The Desktop, Structure of Windows, Windows Explorer, File and Folder Operations, The Search, The Recycle Bin, Configuring the Screen, Adding or Removing New Programs using Control Panel, Applications in windows (Paint, Notepad, WordPad, Calculator) 3. Introduction to Business Communication Tools [ MS-Word: Introduction, Starting MS-Word, MS-Word Screen and its Components, Elementary Working with MS-Word MS-Excel: Introduction, Starting MS-Excel, Basics of Spreadsheet, MS-Excel Screen and Its Components, Elementary Working with MS-Excel MS-Powerpoint: Introduction, Starting MS-PowerPoint, Basics of PowerPoint, MS-PowerPoint Screen and Its Components, Elementary Working with MSPowerPoint 4. Introduction to HTML. Introduction to HTML. Working of HTML Creating and loading HTML page, tags 2 Structure of on HTML, Document, Stand Alone Tags Formatting text, Adding Images Creating hyper Links, Tables Sending E-mails through Web Page Sample web pages 5. Use of Computer in Commerce Data Processing, Files and Records, File Organization (Sequential, Direct/Random, Index ) Computer Applications in Business – Need and Scope Computer Applications in various fields of Commerce: Personnel Administration, Accounting, Cost and Budgetary Management, Purchasing, Banking, Insurance and Stock-broking, e-governance Introduction to E-Commerce, Evolution of E-Commerce, Role of E- Commerce, E-Commerce Framework, E-Commerce Categories Term - II Unit Topic No 1. Internet and Internet application Introduction, Internet evolution Working of Internet, Use of Internet Overview of World Wide Web (Web Server and Client) Introduction to Search engine and Searching the Web Downloading files Introduction to Web Browsers Working with E-mail (creation and use of the same) 2. Electronic Data Interchange Introduction to EDI EDI Architecture Financial EDI Overview of the technology involved in EDI 3 3. Electronic Payment System Introduction to EPS Introduction to EFT (Electronic Fund Transfer) Introduction to SET (Secure Electronic Transaction) Business requirement addressed by SET Introduction to Digital Signature and Digital Certificates , Stages of SET Types of Payment System: Digital Cash, Electronic Cheque, Smart Card, Credit/Debit Card 4. Introduction to HTML. Introduction to HTML. Working of HTML Creating and loading HTML page, tags Structure of on HTML, Document, Stand Alone Tags Formatting text, Adding Images Creating hyper Links, Tables Sending E-mails through Web Page Sample web pages 5. Introduction To Web page Design Introduction to Web design, Types of Web Pages Web design Pyramid Building web sites Web development process model 6. Designing The web pages Page size, Page type, Page margin, Entrance page Exit page, Graphics in Webpage design Animation Effect, Sound Effect Color Effect Uploading the web site (Web space, Domain Name, Hosting the web site) 7. Internet Security Security, Privacy Ethical Issues & Cyber Law 4 Term I 5 1. Introduction to Computer Fundamentals 1.1 Introduction to Computer Computer is an advanced electronic device that takes raw data as input from the user and processes it under the control of set of instructions (called program), gives the result (output), and saves it for the future use. This Computer Fundamentals tutorial covers a foundational understanding of computer hardware, software, operating systems, peripherals etc. These notes provide a general introduction to computers systems. A computer system is made up of both hardware and software. Software is another term for computer program. Software controls the computer and makes it do useful work. Without software a computer is useless. Hardware refers to the physical components that make up a computer system. These include the computer's processor, memory, monitor, keyboard, mouse, disk drive, printer and so on. In these notes we take a brief look at the functions of the different hardware components. In addition we describe the some of the essential software required for the operation of a computer system. 1.1.1Functionalities of a computer Any digital computer carries out five functions in gross terms: Takes data as input. Stores the data/instructions in its memory and use them when required. Processes the data and converts it into useful information. Generates the output Controls all the above four steps. Definition Computer is an electronic data processing device which accepts and stores data input, processes the data input, and generates the output in a required format. 6 1.1.3Advantages Following list demonstrates the advantages of computers in today's arena. 1) High Speed Computer is a very fast device. It is capable of performing calculation of very large amount of data. The computer has units of speed in microsecond, nanosecond, and even the picosecond. It can perform millions of calculations in a few seconds as compared to man who will spend many months for doing the same task. 2)Accuracy In addition to being very fast, computers are very accurate. The calculations are 100% error free. Computers perform all jobs with 100% accuracy provided that correct input has been given. 3)Storage Capability Memory is a very important characteristic of computers. A computer has much more storage capacity than human beings. It can store large amount of data. It can store any type of data such as images, videos, text, audio and many others. 4)Diligence Unlike human beings, a computer is free from monotony, tiredness and lack of concentration. It can work continuously without any error and boredom. It can do repeated work with same speed and accuracy. 5)Versatility A computer is a very versatile machine. A computer is very flexible in performing the jobs to be done. This machine can be used to solve the problems related to various fields. At one instance, it may be solving a complex scientific problem and the very next moment it may be playing a card game. 6)Reliability A computer is a reliable machine. Modern electronic components have long lives. Computers are designed to make maintenance easy. 7)Automation 7 Computer is an automatic machine. Automation means ability to perform the given task automatically. Once a program is given to computer i.e., stored in computer memory, the program and instruction can control the program execution without human interaction. 8)Reduction in Paper Work The use of computers for data processing in an organization leads to reduction in paper work and results in speeding up a process. As data in electronic files can be retrieved as and when required, the problem of maintenance of large number of paper files gets reduced. 9)Reduction in Cost Though the initial investment for installing a computer is high but it substantially reduces the cost of each of its transaction. 1.1.4Disadvantages Following list demonstrates the disadvantages of computers in today's arena 1)No I.Q A computer is a machine that has no intelligence to perform any task. Each instruction has to be given to computer. A computer cannot take any decision on its own. 2)Dependency It functions as per a user’s instruction, so it is fully dependent on human being 3)Environment The operating environment of computer should be dust free and suitable. 4)No Feeling Computers have no feelings or emotions. It cannot make judgement based on feeling, taste, experience, and knowledge unlike a human being. 1.1.5 Components of computer All types of computers follow a same basic logical structure and perform the following five basic operations for converting raw input data into information useful to their users. Sr.No. Operation Description The process of entering data and instructions into the computer 1 Take Input system 8 Saving data and instructions so that they are available for 2 Store Data processing as and when required. Performing arithmetic, and logical operations on data in order to 3 Processing Data convert them into useful information. Output The process of producing useful information or results for the 4 Information user, such as a printed report or visual display. Control the Directs the manner and sequence in which all of the above 5 workflow operations are performed. Input Unit This unit contains devices with the help of which we enter data into computer. This unit makes link between user and computer. The input devices translate the information into the form understandable by computer. CPU (Central Processing Unit) CPU is considered as the brain of the computer. CPU performs all types of data processing operations. It stores data, intermediate results and instructions(program). It controls the operation of all parts of computer. CPU itself has following three components ALU(Arithmetic Logic Unit) Memory Unit Control Unit Output Unit Output unit consists of devices with the help of which we get the information from computer. This unit is a link between computer and users. Output devices translate the computer's output into the form understandable by users. 9 1.1.6 Types of Computer Computers can be broadly classified by their speed and computing power. Sr.No. Type Specifications PC (Personal It is a single user computer system having moderately powerful 1 Computer) microprocessor It is also a single user computer system which is similar to 2 WorkStation personal computer but have more powerful microprocessor. It is a multi-user computer system which is capable of 3 Mini Computer supporting hundreds of users simultaneously. It is a multi-user computer system which is capable of 4 Main Frame supporting hundreds of users simultaneously. Software technology is different from minicomputer. It is an extremely fast computer which can execute hundreds of 5 Supercomputer millions of instructions per second. 1)PC (Personal Computer) A PC can be defined as a small, relatively inexpensive computer designed for an individual user. PCs are based on the microprocessor technology that enables manufacturers to put an entire CPU on one chip. Businesses use personal computers for word processing, accounting, desktop publishing, and for running spreadsheet and database management applications. At home, the most popular use for personal computers is playing games and surfing Internet. Although personal computers are designed as single-user systems, these systems are normally linked together to form a network. In terms of power, now-a-days High-end models of the Macintosh and PC offer the same computing power and graphics capability as low-end workstations by Sun Microsystems, Hewlett-Packard, and Dell. 10 2)Workstation Workstation is a computer used for engineering applications (CAD/CAM), desktop publishing, software development, and other such types of applications which require a moderate amount of computing power and relatively high quality graphics capabilities. Workstations generally come with a large, high-resolution graphics screen, large amount of RAM, inbuilt network support, and a graphical user interface. Most workstations also have a mass storage device such as a disk drive, but a special type of workstation, called a diskless workstation, comes without a disk drive. Common operating systems for workstations are UNIX and Windows NT. Like PC, Workstations are also single-user computers like PC but are typically linked together to form a local-area network, although they can also be used as stand-alone systems. 3)Minicomputer It is a midsize multi-processing system capable of supporting up to 250 users simultaneously. 11 4)Mainframe Mainframe is very large in size and is an expensive computer capable of supporting hundreds or even thousands of users simultaneously. Mainframe executes many programs concurrently and supports many simultaneous execution of programs 5)Supercomputer Supercomputers are one of the fastest computers currently available. Supercomputers are very expensive and are employed for specialized applications that require immense amount of mathematical calculations (number crunching). For example, weather forecasting, scientific simulations, (animated) graphics, fluid dynamic calculations, nuclear energy research, electronic design, and analysis of geological data (e.g. in petrochemical prospecting). 12 1.2 Computer System Hardware Hardware represents the physical and tangible components of a computer i.e. the components that can be seen and touched. Examples of Hardware are following: Input devices -- keyboard, mouse etc. Output devices -- printer, monitor etc. Secondary storage devices -- Hard disk, CD, DVD etc. Internal components -- CPU, motherboard, RAM etc. 13 1.2.1 Relationship between Hardware and Software Hardware and software are mutually dependent on each other. Both of them must work together to make a computer produce a useful output. Software cannot be utilized without supporting hardware. Hardware without set of programs to operate upon cannot be utilized and is useless. To get a particular job done on the computer, relevant software should be loaded into the hardware Hardware is a one-time expense. Software development is very expensive and is a continuing expense. Different software applications can be loaded on a hardware to run different jobs. A software acts as an interface between the user and the hardware. If hardware is the 'heart' of a computer system, then software is its 'soul'. Both are complimentary to each other. 1.3 Computer Memory Memory is used to store the information (programs and data) that the computer is currently using. It is sometimes called main or primary memory. One form of memory is called RAM - random access memory. This means that any location in memory may be accessed in the same amount of time as any other location. Memory access means one of two things, either the CPU is reading from a memory location or the CPU is writing to a memory location. When the CPU reads from a memory location, the contents of the memory location are copied to a CPU register. When the CPU writes to a memory location, the CPU copies the contents of a CPU register to the memory 14 location, overwriting the previous contents of the location. The CPU cannot carry out any other operations on memory locations. RAM is a form of short term or volatile memory. Information stored in short term storage is lost when the computer is switched off (or when power fails e.g. if you pull out the power lead!). There is therefore a requirement for permanent or long term storage which is also referred to as secondary storage or auxiliary storage. This role is fulfilled by disk and tape storage. 1.3.1 Random Access Memory (RAM) RAM(Random Access Memory) is the internal memory of the CPU for storing data, program and program result. It is read/write memory which stores data until the machine is working. As soon as the machine is switched off, data is erased. Access time in RAM is independent of the address that is, each storage location inside the memory is as easy to reach as other locations and takes the same amount of time. Data in the RAM can be accessed randomly but it is very expensive. RAM is volatile, i.e. data stored in it is lost when we switch off the computer or if there is a power failure. Hence a backup uninterruptible power system(UPS) is often used with computers. RAM is small, both in terms of its physical size and in the amount of data it can hold. RAM is of two types Static RAM (SRAM) Dynamic RAM (DRAM) 1)Static RAM (SRAM) The word static indicates that the memory retains its contents as long as power is being supplied. However, data is lost when the power gets down due to volatile nature. SRAM chips use a matrix of 6-transistors and no capacitors. Transistors do not require power to prevent leakage, so SRAM need not have to be refreshed on a regular basis. 15 Because of the extra space in the matrix, SRAM uses more chips than DRAM for the same amount of storage space, thus making the manufacturing costs higher. So SRAM is used as cache memory and has very fast access. Characteristic of the Static RAM It has long life There is no need to refresh Faster Used as cache memory Large size Expensive High power consumption 2)Dynamic RAM (DRAM) DRAM, unlike SRAM, must be continually refreshed in order to maintain the data. This is done by placing the memory on a refresh circuit that rewrites the data several hundred times per second. DRAM is used for most system memory because it is cheap and small. All DRAMs are made up of memory cells which are composed of one capacitor and one transistor. Characteristics of the Dynamic RAM It has short data lifetime Need to be refreshed continuously Slower as compared to SRAM Used as RAM Lesser in size Less expensive Less power consumption 1.3.2 - Read Only Memory (ROM) ROM stands for Read Only Memory. The memory from which we can only read but cannot write on it. This type of memory is non-volatile. The information is stored permanently in such memories during manufacture. A ROM, stores such instructions that are required to start a computer. This operation is referred to as bootstrap. ROM chips are not only used in the 16 computer but also in other electronic items like washing machine and microwave oven. Following are the various types of ROM 1)MROM (Masked ROM) The very first ROMs were hard-wired devices that contained a pre-programmed set of data or instructions. These kind of ROMs are known as masked ROMs which are inexpensive. 2)PROM (Programmable Read only Memory) PROM is read-only memory that can be modified only once by a user. The user buys a blank PROM and enters the desired contents using a PROM program. Inside the PROM chip there are small fuses which are burnt open during programming. It can be programmed only once and is not erasable. 3)EPROM(Erasable and Programmable Read Only Memory) The EPROM can be erased by exposing it to ultra-violet light for a duration of up to 40 minutes. Usually, an EPROM eraser achieves this function. During programming, an electrical charge is trapped in an insulated gate region. The charge is retained for more than ten years because the charge has no leakage path. For erasing this charge, ultra-violet light is passed through a quartz crystal window(lid). This exposure to ultra-violet light dissipates the charge. During normal use the quartz lid is sealed with a sticker. 4)EEPROM(Electrically Erasable and Programmable Read Only Memory) The EEPROM is programmed and erased electrically. It can be erased and reprogrammed about ten thousand times. Both erasing and programming take about 4 to 10 ms (milli second). In EEPROM, any location can be selectively erased and programmed. EEPROMs can be erased one byte at a time, rather than erasing the entire chip. Hence, the process of re- programming is flexible but slow. 17 Advantages of ROM The advantages of ROM are as follows: Non-volatile in nature These cannot be accidentally changed Cheaper than RAMs Easy to test More reliable than RAMs These are static and do not require refreshing Its contents are always known and can be verified 1.4 Input/Output Devices: 1.4.1Input Devices Following are few of the important input devices which are used in a computer: Keyboard Mouse Joy Stick Light pen Track Ball Scanner Graphic Tablet Microphone Magnetic Ink Card Reader(MICR) Optical Character Reader(OCR) Bar Code Reader Optical Mark Reader(OMR) 1)Keyboard Keyboard is the most common and very popular input device which helps in inputting data to the computer. The layout of the keyboard is like that of traditional typewriter, although there are some additional keys provided for performing additional functions. Keyboards are of two sizes 84 keys or 101/102 keys, but now keyboards with 104 keys or 108 keys are also available for Windows and Internet. 18 The keys on the keyboard are as follows: Sr.No Keys Description These keys include the letter keys (A-Z) and digit keys (0-9) 1 Typing Keys which generally give same layout as that of typewriters. It is used to enter numeric data or cursor movement. Generally, it consists of a set of 17 keys that are laid out in 2 Numeric Keypad the same configuration used by most adding machines and calculators. The twelve function keys are present on the keyboard which are arranged in a row at the top of the keyboard. Each 3 Function Keys function key has unique meaning and is used for some specific purpose. These keys provide cursor and screen control. It includes four directional arrow keys. Control keys also include Home, End, 4 Control keys Insert, Delete, Page Up, Page Down, Control(Ctrl), Alternate(Alt), Escape(Esc). Keyboard also contains some special purpose keys such as Special Purpose 5 Enter, Shift, Caps Lock, Num Lock, Space bar, Tab, and Print Keys Screen. 2)Mouse Mouse is most popular pointing device. It is a very famous cursor-control device having a small palm size box with a round ball at its base which senses the movement of mouse and sends corresponding signals to CPU when the mouse buttons are pressed. 19 Generally it has two buttons called left and right button and a wheel is present between the buttons. Mouse can be used to control the position of cursor on screen, but it cannot be used to enter text into the computer. Advantages Easy to use Not very expensive Moves the cursor faster than the arrow keys of keyboard. 3)Joystick Joystick is also a pointing device which is used to move cursor position on a monitor screen. It is a stick having a spherical ball at its both lower and upper ends. The lower spherical ball moves in a socket. The joystick can be moved in all four directions. The function of joystick is similar to that of a mouse. It is mainly used in Computer Aided Designing(CAD) and playing computer games. 20 4)Light Pen Light pen is a pointing device which is similar to a pen. It is used to select a displayed menu item or draw pictures on the monitor screen. It consists of a photocell and an optical system placed in a small tube. When the tip of a light pen is moved over the monitor screen and pen button is pressed, its photocell sensing element detects the screen location and sends the corresponding signal to the CPU. 5)Track Ball Track ball is an input device that is mostly used in notebook or laptop computer, instead of a mouse. This is a ball which is half inserted and by moving fingers on ball, pointer can be moved. Since the whole device is not moved, a track ball requires less space than a mouse. A track ball comes in various shapes like a ball, a button and a square. 6)Scanner Scanner is an input device which works more like a photocopy machine. It is used when some information is available on a paper and it is to be transferred to the hard disc of the computer for further manipulation. Scanner captures images from the source which are then converted into the digital form that can be stored on the disc. These images can be edited before they are printed. 21 7)Digitizer Digitizer is an input device which converts analog information into digital form. Digitizer can convert a signal from the television or camera into a series of numbers that could be stored in a computer. They can be used by the computer to create a picture of whatever the camera had been pointed at. Digitizer is also known as Tablet or Graphics Tablet because it converts graphics and pictorial data into binary inputs. A graphic tablet as digitizer is used for doing fine works of drawing and image manipulation applications. 8)Microphone Microphone is an input device to input sound that is then stored in digital form. The microphone is used for various applications like adding sound to a multimedia presentation or for mixing music. 22 9)Magnetic Ink Card Reader(MICR) MICR input device is generally used in banks because of a large number of cheques to be processed every day. The bank's code number and cheque number are printed on the cheques with a special type of ink that contains particles of magnetic material that are machine readable. This reading process is called Magnetic Ink Character Recognition (MICR). The main advantages of MICR is that it is fast and less error prone. Optical Character Reader(OCR) OCR is an input device used to read a printed text. OCR scans text optically character by character, converts them into a machine readable code and stores the text on the system memory. 23 10)Bar Code Readers Bar Code Reader is a device used for reading bar coded data (data in form of light and dark lines). Bar coded data is generally used in labelling goods, numbering the books etc. It may be a hand held scanner or may be embedded in a stationary scanner. Bar Code Reader scans a bar code image, converts it into an alphanumeric value which is then fed to the computer to which bar code reader is connected. 1.4.2 Output Devices Following are few of the important output devices which are used in a computer. Monitors Graphic Plotter Printer 1.4.3Monitors 24 Monitors, commonly called as Visual Display Unit (VDU), are the main output device of a computer. It forms images from tiny dots, called pixels that are arranged in a rectangular form. The sharpness of the image depends upon the number of pixels. There are two kinds of viewing screen used for monitors. Cathode-Ray Tube (CRT) Flat- Panel Display 1)Cathode-Ray Tube (CRT) Monitor The CRT display is made up of small picture elements called pixels. The smaller the pixels, the better the image clarity, or resolution. It takes more than one illuminated pixel to form whole character, such as the letter ‘e’ in the word help. A finite number of characters can be displayed on a screen at once. The screen can be divided into a series of character boxes - fixed location on the screen where a standard character can be placed. Most screens are capable of displaying 80 characters of data horizontally and 25 lines vertically. There are some disadvantages of CRT: Large in Size High power consumption 2)Flat-Panel Display Monitor The flat-panel display refers to a class of video devices that have reduced volume, weight and power requirement in comparison to the CRT. You can hang them on walls or wear them on your wrists. Current uses of flat-panel displays include calculators, video games, monitors, laptop computer, graphics display. The flat-panel display is divided into two categories: 25 Emissive Displays - The emissive displays are devices that convert electrical energy into light. Example are plasma panel and LED(Light-Emitting Diodes). Non-Emissive Displays - The Non-emissive displays use optical effects to convert sunlight or light from some other source into graphics patterns. Example is LCD(Liquid-Crystal Device) 1.4.4Printers Printer is an output device, which is used to print information on paper. There are two types of printers: Impact Printers Non-Impact Printers A)Impact Printers The impact printers print the characters by striking them on the ribbon which is then pressed on the paper. Characteristics of Impact Printers are the following: Very low consumable costs Very noisy Useful for bulk printing due to low cost There is physical contact with the paper to produce an image 26 These printers are of two types Character printers Line printers Character Printers Character printers are the printers which print one character at a time. These are further divided into two types: Dot Matrix Printer(DMP) Daisy Wheel 1)Dot Matrix Printer In the market one of the most popular printers is Dot Matrix Printer. These printers are popular because of their ease of printing and economical price. Each character printed is in form of pattern of dots and head consists of a Matrix of Pins of size (5*7, 7*9, 9*7 or 9*9) which come out to form a character that is why it is called Dot Matrix Printer. Advantages Inexpensive Widely Used Other language characters can be printed Disadvantages Slow Speed Poor Quality 27 2)Daisy Wheel Head is lying on a wheel and pins corresponding to characters are like petals of Daisy (flower name) that is why it is called Daisy Wheel Printer. These printers are generally used for word-processing in offices which require a few letters to be sent here and there with very nice quality. Advantages More reliable than DMP Better quality The fonts of character can be easily changed Disadvantages Slower than DMP Noisy More expensive than DMP 3)Line Printers Line printers are the printers which print one line at a time. 28 These are of further two types Drum Printer Chain Printer 4)Drum Printer This printer is like a drum in shape so it is called drum printer. The surface of drum is divided into number of tracks. Total tracks are equal to size of paper i.e. for a paper width of 132 characters, drum will have 132 tracks. A character set is embossed on track. The different character sets available in the market are 48 character set, 64 and 96 characters set. One rotation of drum prints one line. Drum printers are fast in speed and can print 300 to 2000 lines per minute. Advantages Very high speed Disadvantages Very expensive Characters fonts cannot be changed 5)Chain Printer In this printer, chain of character sets are used so it is called Chain Printer. A standard character set may have 48, 64, or 96 characters. Advantages Character fonts can easily be changed. Different languages can be used with the same printer. Disadvantages Noisy B)Non-impact Printers Non-impact printers print the characters without using ribbon. These printers print a complete page at a time so they are also called as Page Printers. These printers are of two types Laser Printers Inkjet Printers Characteristics of Non-impact Printers 29 Faster than impact printers. They are not noisy. High quality. Support many fonts and different character size. 1)Laser Printers These are non-impact page printers. They use laser lights to produce the dots needed to form the characters to be printed on a page. Advantages Very high speed Very high quality output Give good graphics quality Support many fonts and different character size Disadvantages Expensive. Cannot be used to produce multiple copies of a document in a single printing. 2)Inkjet Printers Inkjet printers are non-impact character printers based on a relatively new technology. They print characters by spraying small drops of ink onto paper. Inkjet printers produce high quality output with presentable features. 30 They make less noise because no hammering is done and these have many styles of printing modes available. Colour printing is also possible. Some models of Inkjet printers can produce multiple copies of printing also. Advantages High quality printing More reliable Disadvantages Expensive as cost per page is high Slow as compared to laser printer 1.5 Interaction between User and Computer Human–computer interaction (HCI) involves the study, planning, design and uses of the interfaces between people (users) and computers. HCI (human-computer interaction) is the study of how people interact with computers and to what extent computers are or are not developed for successful interaction with human beings. HCI is a very broad discipline that encompasses different specialties with different concerns regarding computer development: computer science is concerned with the application design and engineering of the human interfaces; sociology and anthropology are concerned with the interactions between technology, work and organization and the way that human systems and technical systems mutually adapt to each other; ergonomics is concerned with the safety of computer systems and the safe limits of human cognition and sensation; psychology is concerned with the cognitive processes of humans and the behavior of users; linguistics is concerned with the development of human and machine languages and the relationship between the two. 31 1.6 Introduction to free and open source software Open Source Software: Software for which: The source code is available to the end-user; The source code can be modified by the end-user; There are no restrictions on redistribution or use; The licensing conditions are usually intended to facilitate continued re-use and wide availability of the software, in both commercial and non-commercial contexts; The cost of acquisition to the end-user is often minimal. 1.7 Definition of computer virus A computer virus is a program or piece of code that is loaded onto your computer without your knowledge and runs against your wishes. Viruses can also replicate themselves. All computer viruses are man-made. A simple virus that can make a copy of itself over and over again is relatively easy to produce. Even such a simple virus is dangerous because it will quickly use all available memory and bring the system to a halt. An even more dangerous type of virus is one capable of transmitting itself across networks and bypassing security systems. 32 In computers, a virus is a program or programming code that replicates by being copied or initiating its copying to another program, computer boot sector or document. A computer virus is a program designed to harm or cause harm on an infected computer. Its spreads through e-mail attachments, portable devices, websites containing malicious scripts and file downloads. A computer virus attaches itself to the host files and always activate whenever you open the infected files. The virus can replicate itself and then infect the other files on your computer causing more damage. Below is a list of different types of computer viruses and what they do. 7.1.1 Types of computer virus 1. Resident Viruses This type of virus is a permanent which dwells in the RAM memory. From there it can overcome and interrupt all of the operations executed by the system: corrupting files and programs that are opened, closed, copied, renamed etc. Examples include: Randex, CMJ, Meve, and MrKlunky. 2. Multipartite Viruses Multipartite viruses are distributed through infected media and usually hide in the memory. Gradually, the virus moves to the boot sector of the hard drive and infects executable files on the hard drive and later across the computer system. 3. Direct Action Viruses The main purpose of this virus is to replicate and take action when it is executed. When a specific condition is met, the virus will go into action and infect files in the directory or folder that it is in and in directories that are specified in the AUTOEXEC.BAT file PATH. This batch file is always located in the root directory of the hard disk and carries out certain operations when the computer is booted. 4. Overwrite Viruses Virus of this kind is characterized by the fact that it deletes the information contained in the files that it infects, rendering them partially or totally useless once they have been infected. The only way to clean a file infected by an overwrite virus is to delete the file completely, thus losing the original content. Examples of this virus include: Way, Trj.Reboot, Trivial.88.D. 5. Boot Virus This type of virus affects the boot sector of a floppy or hard disk. This is a crucial part of a 33 disk, in which information on the disk itself is stored together with a program that makes it possible to boot (start) the computer from the disk. The best way of avoiding boot viruses is to ensure that floppy disks are write-protected and never start your computer with an unknown floppy disk in the disk drive. Examples of boot viruses include: Polyboot.B, AntiEXE. 6. Macro Virus Macro viruses infect files that are created using certain applications or programs that contain macros. These mini-programs make it possible to automate series of operations so that they are performed as a single action, thereby saving the user from having to carry them out one by one. Examples of macro viruses: Relax, Melissa.A, Bablas, O97M/Y2K. 7. Directory Virus Directory viruses change the paths that indicate the location of a file. By executing a program (file with the extension.EXE or.COM) which has been infected by a virus, you are unknowingly running the virus program, while the original file and program have been previously moved by the virus. Once infected it becomes impossible to locate the original files. 8. Polymorphic Virus Polymorphic viruses encrypt or encode themselves in a different way (using different algorithms and encryption keys) every time they infect a system. This makes it impossible for anti-viruses to find them using string or signature searches (because they are different in each encryption) and also enables them to create a large number of copies of themselves. Examples include: Elkern, Marburg, Satan Bug, and Tuareg. 9. File Infectors This type of virus infects programs or executable files (files with an.EXE or.COM extension). When one of these programs is run, directly or indirectly, the virus is activated, producing the damaging effects it is programmed to carry out. The majority of existing viruses belongs to this category, and can be classified depending on the actions that they carry out. 10. Encrypted Viruses This type of viruses consists of encrypted malicious code, decrypted module. The viruses use encrypted code technique which make antivirus software hardly to detect them. The antivirus program usually can detect this type of viruses when they try spread by decrypted 34 themselves. 11. Companion Viruses Companion viruses can be considered file infector viruses like resident or direct action types. They are known as companion viruses because once they get into the system they "accompany" the other files that already exist. In other words, in order to carry out their infection routines, companion viruses can wait in memory until a program is run (resident viruses) or act immediately by making copies of themselves (direct action viruses). Some examples include: Stator, Asimov.1539, and Terrax.1069 12. Network Virus Network viruses rapidly spread through a Local Network Area (LAN), and sometimes throughout the internet. Generally, network viruses multiply through shared resources, i.e., shared drives and folders. When the virus infects a computer, it searches through the network to attack its new potential prey. When the virus finishes infecting that computer, it moves on to the next and the cycle repeats itself. The most dangerous network viruses are Nimda and SQLSlammer. 13. Nonresident Viruses This type of viruses is similar to Resident Viruses by using replication of module. Besides that, Nonresident Viruses role as finder module which can infect to files when it found one (it will select one or more files to infect each time the module is executed). 14. Stealth Viruses Stealth Viruses is some sort of viruses which try to trick anti-virus software by intercepting its requests to the operating system. It has ability to hide itself from some antivirus software programs. Therefore, some antivirus program cannot detect them. 15. Sparse Infectors In order to spread widely, a virus must attempt to avoid detection. To minimize the probability of its being discovered a virus could use any number of different techniques. It might, for example, only infect every 20th time a file is executed; it might only infect files whose lengths are within narrowly defined ranges or whose names begin with letters in a certain range of the alphabet. There are many other possibilities. 16. Spacefiller (Cavity) Viruses Many viruses take the easy way out when infecting files; they simply attach themselves to the end of the file and then change the start of the program so that it first points to the virus and then to the actual program code. Many viruses that do this also implement some stealth techniques so you don't see the increase in file length when the virus is active in memory. 35 A spacefiller (cavity) virus, on the other hand, attempts to be clever. Some program files, for a variety of reasons, have empty space inside of them. This empty space can be used to house virus code. A spacefiller virus attempts to install itself in this empty space while not damaging the actual program itself. An advantage of this is that the virus then does not increase the length of the program and can avoid the need for some stealth techniques. The Lehigh virus was an early example of a spacefiller virus. 17. FAT Virus The file allocation table or FAT is the part of a disk used to connect information and is a vital part of the normal functioning of the computer. This type of virus attack can be especially dangerous, by preventing access to certain sections of the disk where important files are stored. Damage caused can result in information losses from individual files or even entire directories. 18. Worms A worm is technically not a virus, but a program very similar to a virus; it has the ability to self-replicate, and can lead to negative effects on your system and most importantly they are detected and eliminated by antiviruses. Examples of worms include: PSWBugbear.B, Lovgate.F, Trile.C, Sobig.D, Mapson. 19. Trojans or Trojan Horses Another unsavory breed of malicious code (not a virus as well) are Trojans or Trojan horses, which unlike viruses do not reproduce by infecting other files, nor do they self-replicate like worms. 20. Logic Bombs They are not considered viruses because they do not replicate. They are not even programs in their own right but rather camouflaged segments of other programs. Their objective is to destroy data on the computer once certain conditions have been met. Logic bombs go undetected until launched, and the results can be destructive. 1.7.2Use of Antivirus software Antivirus or anti-virus software (often abbreviated as AV), sometimes known as anti- malware software, is computer software used to prevent, detect and remove malicious software. Antivirus (or anti- virus)software is used to safeguard a computer from malware, including viruses, computer worms, and Trojan horses 36 Antivirus software may also remove or prevent spyware and adware, along with other forms of malicious programs. Free antivirus software generally only searches your computer using signature-based detection which involves looking for patterns of data that are known to be related to already-identified malware. Paid antivirus software will usually also include heuristics to catch new, or zero-day threats, by either using genetic signatures to identify new variants of existing virus code or by running the file in a virtual environment (also called a sandbox), and watching what it does to see if it has malicious intent. Virus designers, however, usually test their malicious code against the major antivirus types of malware, specifically ransomware, use polymorphic code to make it difficult to be detected by antivirus software. Besides using antivirus software to keep your computer safe and running smoothly, it is also always a good idea to be proactive: make sure your web browser is updated to the latest version, use a firewall, only download programs from websites you trust and always surf the web using a standard user account, rather than your administrator one. 37 2.Basics Of Operating System 2.1 Definition of Operating System: “An Operating system is a program that controls the execution of application programs and acts as an interface between the user of a computer and the computer hardware.” A more common definition is that the operating system is the one program running at all times on the computer (usually called the kernel), with all else being applications programs. An Operating system is concerned with the allocation of resources and services, such as memory, processors, devices and information. The Operating System correspondingly includes programs to manage these resources, such as a traffic controller, a scheduler, memory management module, I/O programs, and a file system. 2.2 Types Of Operating Systems: Operating systems are there from the very first computer generation. Operating systems keep evolving over the period of time. Following are few of the important types of operating system which are most commonly used. 1)Batch Operating System The users of batch operating system do not interact with the computer directly. Each user prepares his job on an off-line device like punch cards and submits it to the computer operator. To speed up processing, jobs with similar needs are batched together and run as a group. Thus, the programmers left their programs with the operator. The operator then sorts programs into batches with similar requirements. The problems with Batch Systems are following. Lack of interaction between the user and job. CPU is often idle, because the speeds of the mechanical I/O devices are slower than CPU. Difficult to provide the desired priority. 2)Time Sharing Operating System Time sharing is a technique which enables many people, located at various terminals, to use a particular computer system at the same time. Time-sharing or multitasking is a logical extension of multiprogramming. Processor's time which is shared among multiple users simultaneously is termed as time-sharing. The main difference between Multiprogrammed Batch Systems and Time-Sharing Systems is that in case of multiprogrammed batch systems, objective is to maximize processor use, whereas in Time-Sharing Systems objective is to minimize response time. Multiple jobs are executed by the CPU by switching between them, but the switches occur so frequently. Thus, the user can receive an immediate response. For example, in a transaction processing, processor execute each user program in a short burst or quantum of computation. That is if n users are present, each user can get time quantum. When the user submits the command, the response time is in few seconds at most. Operating system uses CPU scheduling and multiprogramming to provide each user with a small portion of a time. Computer systems that were designed primarily as batch systems have been modified to time-sharing systems. Advantages of Timesharing operating systems are following Provide advantage of quick response. Avoids duplication of software. 38 Reduces CPU idle time. Disadvantages of Timesharing operating systems are following. Problem of reliability. Question of security and integrity of user programs and data. Problem of data communication. 3)Distributed Operating System Distributed systems use multiple central processors to serve multiple real time application and multiple users. Data processing jobs are distributed among the processors accordingly to which one can perform each job most efficiently. The processors communicate with one another through various communication lines (such as high-speed buses or telephone lines). These are referred as loosely coupled systems or distributed systems. Processors in a distributed system may vary in size and function. These processors are referred as sites, nodes, and computers and so on. The advantages of distributed systems are following. With resource sharing facility user at one site may be able to use the resources available at another. Speedup the exchange of data with one another via electronic mail. If one site fails in a distributed system, the remaining sites can potentially continue operating. Better service to the customers. Reduction of the load on the host computer. Reduction of delays in data processing. 4)Network Operating System Network Operating System runs on a server and and provides server the capability to manage data, users, groups, security, applications, and other networking functions. The primary purpose of the network operating system is to allow shared file and printer access among multiple computers in a network, typically a local area network (LAN), a private network or to other networks. Examples of network operating systems are Microsoft Windows Server 2003, Microsoft Windows Server 2008, UNIX, Linux, Mac OS X, Novell NetWare, and BSD. The advantages of network operating systems are following. Centralized servers are highly stable. Security is server managed. Upgrades to new technologies and hardware can be easily integrated into the system. Remote access to servers is possible from different locations and types of systems. The disadvantages of network operating systems are following. High cost of buying and running a server. Dependency on a central location for most operations. Regular maintenance and updates are required. 5)Real time Operating System Real time system is defines as a data processing system in which the time interval required to process and respond to inputs is so small that it controls the environment. Real time processing is always on line whereas on line system need not be real time. The time taken by the system to respond to an input and display of required updated information is termed as response time. So in this method response time is very less as compared to the online processing. 39 Real-time systems are used when there are rigid time requirements on the operation of a processor or the flow of data and real-time systems can be used as a control device in a dedicated application. Real-time operating system has well-defined, fixed time constraints otherwise system will fail. For example Scientific experiments, medical imaging systems, industrial control systems, weapon systems, robots, and home-appliance controllers, Air traffic control system etc. There are two types of real-time operating systems. Hard real-time systems Hard real-time systems guarantee that critical tasks complete on time. In hard real-time systems secondary storage is limited or missing with data stored in ROM. In these systems virtual memory is almost never found. Soft real-time systems Soft real time systems are less restrictive. Critical real-time task gets priority over other tasks and retains the priority until it completes. Soft real-time systems have limited utility than hard real-time systems. For example, Multimedia, virtual reality, Advanced Scientific Projects like undersea exploration and planetary rovers etc. 2.3 Functions of an Operating System: Following are some of important functions of an operating System Memory Management Processor Management Device Management File Management Security Control over system performance Job accounting Error detecting aids Coordination between other software and users 1) Memory Management Memory management refers to management of Primary Memory or Main Memory. Main memory is a large array of words or bytes where each word or byte has its own address. Main memory provides a fast storage that can be access directly by the CPU. So for a program to be executed, it must in the main memory. Operating System does the following activities for memory management. Keeps tracks of primary memory i.e. what part of it are in use by whom, what part are not in use. In multiprogramming, OS decides which process will get memory when and how much. Allocates the memory when the process requests it to do so. De-allocates the memory when the process no longer needs it or has been terminated. 2) Processor Management In multiprogramming environment, OS decides which process gets the processor when and how much time. This function is called process scheduling. Operating System does the following activities for processor management. Keeps tracks of processor and status of process. Program responsible for this task is known as traffic controller. 40 Allocates the processor (CPU) to a process. De-allocates processor when processor is no longer required. 3) Device Management OS manages device communication via their respective drivers. Operating System does the following activities for device management. Keeps tracks of all devices. Program responsible for this task is known as the I/O controller. Decides which process gets the device when and for how much time. Allocates the device in the efficient way. De-allocates devices. 4)File Management A file system is normally organized into directories for easy navigation and usage. These directories may contain files and other directions. Operating System does the following activities for file management. Keeps track of information, location, uses, status etc. The collective facilities are often known as file system. Decides who gets the resources. Allocates the resources. De-allocates the resources 5)Other Important Activities Following are some of the important activities that Operating System does. Security -- By means of password and similar other techniques, preventing unauthorized access to programs and data. Control over system performance -- Recording delays between request for a service and response from the system. Job accounting -- Keeping track of time and resources used by various jobs and users. Error detecting aids -- Production of dumps, traces, error messages and other debugging and error detecting aids. Coordination between other software and users -- Coordination and assignment of compilers, interpreters, assemblers and other software to the various users of the computer systems. 2.4 Working With Windows Operating System The Desktop : The desktop is the main screen area that you see after you turn on your computer and log on to Windows. When you open programs or folders, they appear on the desktop. You can also put things on the desktop, such as files and folders, and arrange them as you want. Working with desktop icons Icons are small pictures that represent files, folders, programs, and other items. When 41 you first start Windows, you'll see at least one icon on your desktop: The Recycle Bin. Some examples of desktop icons are shown in picture. Double-clicking a desktop icon starts or opens the item it represents. Adding and removing icons from the desktop You can choose which icons appear on the desktop—you can add or remove an icon at any time. If you want easy access from the desktop to your favorite files or programs, you can create shortcuts to them. A shortcut is an icon that represents a link to an item, rather than the item itself. When you double-click a shortcut, the item opens. If you delete a shortcut, only the shortcut is removed, not the original item. You can identify shortcuts by the arrow on their icon. Common desktop icons include Computer, your personal folder, the Recycle Bin, and Control Panel. 1. Right-click an empty area of the desktop, and then click Personalize. 2. In the left pane, click Change desktop icons. 3. Under Desktop icons, select the check box for each icon that you want to add to the desktop, or clear the check box for each icon that you want to remove from the desktop, and then click OK. To move a file from a folder to the desktop 1. Open the folder that contains the file. 2. Drag the file to the desktop. Moving icons around Windows stacks icons in columns on the left side of the desktop. But you're not stuck with that arrangement. You can move an icon by dragging it to a new place on the desktop. You can also have Windows automatically arrange your icons. Right-click an empty area of the desktop, click View, and then clickAuto arrange icons. Windows stacks your icons in the upper-left corner and locks them in place. To unlock the icons so that you can move them again, click Auto arrange icons again, clearing the check mark next to it. Selecting multiple icons To move or delete a bunch of icons at once, you must first select all of them. Click an empty area of the desktop and drag the mouse. Surround the icons that you want to select with the rectangle that appears. Then release the mouse button. Now you can drag the icons as a group or delete them. 42 Hiding desktop icons If you want to temporarily hide all of your desktop icons without removing them, right-click an empty part of the desktop, click View, and then click Show desktop icons to clear the check mark from that option. Now no icons are displayed on the desktop. You can get them back by clicking Show desktop icons again. Windows Explorer: Windows Explorer is the file management application in windows. Windows explorer can be used to navigate your hard drive and display the contents of the folders and subfolders you use to organize your files on your hard drive. Windows Explorer is automatically launched any time you open a folder in windows XP. The Recycle Bin When you delete a file or folder, it doesn't actually get deleted,it goes to the Recycle Bin. That's a good thing, because if you want that deleted file, you can get it back. If you won't need the deleted items again, you can empty the Recycle Bin. Doing that will permanently delete the items and reclaim any disk space they were using. Start Menu: The Start menu is the main gateway to your computer's programs, folders, and settings. It's called a menu because it provides a list of choices. Use the Start menu to do these common activities: Start programs Open commonly used folders Search for files, folders, and programs Adjust computer settings Get help with the Windows operating system Turn off the computer Log off from Windows or switch to a different user account. Getting started with the Start menu 43 To open the Start menu, click the Start button in the lower-left corner of your screen. Or, press the Windows logo key on your keyboard. The Start menu has three basic parts: The large left pane shows a short list of programs on your computer. Clicking All Programs displays a complete list of programs. At the bottom of the left pane is the search box, which allows you to look for programs and files on your computer by typing in search terms. The right pane provides access to commonly used folders, files, settings, and features. It's also where you go to log off from Windows or turn off your computer. Opening programs from the Start menu 1. Start menu is used to open programs installed on your computer. To open a program in the left pane of the Start menu, click it. 2. Clicking All Programs, The left pane displays a long list of programs. 3. Clicking one of the program icons starts the program, and the Start menu closes. 4. Move the pointer over its icon or name, a box appears that contains a description of the program. The search box The search box is one of the most convenient ways to find things on your computer. The exact location of the items doesn't matter. It will also search your e-mail messages, saved instant messages, appointments, and contacts. To use the search box, open the Start menu and start typing. You don't need to click inside the box first. As you type, the search results appear above the search box in the left pane of the Start menu. A program, file, or folder will appear as a search result if: Any word in its title matches or begins with your search term. Any text in the actual contents of the file matches or begins with your search term. Any word in a property of the file, such as the author, matches or begins with your search term. Click any search result to open it. Or, click the Clear button to clear the search results and return to the main programs list. You can also click See more results to search your entire computer. Search box also searches your Internet favorites and the history of websites you've visited. If any of these webpages include the search term, they appear under a heading called "Files." The right pane includes 44 1. Personal folder. This folder, in turn, contains user-specific files, including the My Documents, My Music, My Pictures, and My Videos folders. 2. Documents. Opens the Documents library, where you can access & open text files, spreadsheets, etc. 3. Pictures. Opens the Pictures library, where you can access and view digital pictures and graphics files. 4. Music. Opens the Music library, where you can access and play music and other audio files. 5. Games. Opens the Games folder, where you can access all of the games on your computer. 6. Computer. Opens a window where you can access disk drives, cameras, printers, scanners, and other hardware connected to your computer. 7. Control Panel. Opens Control Panel, where you can customize the appearance and functionality of your computer, install or uninstall programs, set up network connections, and manage user accounts. 8. Devices and Printers. Opens a window where you can view information about the printer, mouse, and other devices installed on your computer. 9. Default Programs. Opens a window where you can choose which program you want Windows to use for activities such as web browsing. 10. Help and Support. Opens Windows Help and Support, where you can browse and search Help topics about using Windows and your computer. At the bottom of the right pane is the Shut down button. Click the Shut down button to turn off your computer. Clicking the arrow next to the Shut down button displays a menu with additional options for switching users, logging off, restarting, or shutting down. Taskbar: The taskbar is the long horizontal bar at the bottom of your screen. It has three main sections: The Start button , which opens the Start menu. The middle section, which shows you which programs & files you have open & allows you to quickly switch between them. The notification area, which includes a clock and icons (small pictures) that communicate the status of certain programs and computer settings. Keep track of your windows If you open one or more program/file at a time, it's hard to see what else is what you've already opened. Whenever you open a program, folder, or file, Windows creates a corresponding button on the taskbar. 45 The button shows an icon that represents the open program. In the picture below, two programs are open—Calculator and Minesweeper—and each has its own button on the taskbar. It also highlights the icon whose window is active. Click a taskbar button to switch to that window The notification area The notification area, at the right of the taskbar, includes a clock and a group of icons. These icons communicate the status of something on your computer or provide access to certain settings. When you move your pointer to a particular icon, you will see that icon's name or the status of a setting. Double-clicking an icon in the notification area usually opens the program or setting associated with it. For example, double-clicking the volume icon opens the volume controls. Windows hides icons in the notification area when you haven't used them in a while. If icons become hidden, click the Show hidden icons button to temporarily display the hidden icons. Click the Show hidden icons button to display all icons in the notification area Using menus, buttons, bars, and boxes Menus, buttons, scroll bars, and check boxes are examples of controls that you operate with your mouse or keyboard. These controls allow you to select commands, change settings, or work with windows. Menus: Most programs contain hundreds of commands that you use to work the program. Many of these commands are organized under menus. A program menu shows you a list of choices. To choose one of the commands listed in a menu, click it. Sometimes menus show submenus. Recognizing menus isn't always easy, because not all menu controls look same or even appear on a menu bar. When you see an arrow next to a word or picture, you're probably looking at a menu control. Scroll bars 46 When a document, webpage, or picture exceeds the size of its window, scroll bars appear to allow you to see the information that is currently out of view. The following picture shows the parts of a scroll bar. To use a scroll bar: Click the up or down scroll arrows to scroll the window's contents up or down in small steps. Hold down the mouse button to scroll continuously. Click an empty area of a scroll bar above or below the scroll box to scroll up or down one page. Drag a scroll box up, down, left, or right to scroll the window in that direction. Command buttons A command button performs a command when you click it. You'll most often see them in dialog boxes, which are small windows that contain options for completing a task. For example, if you close a Paint picture without saving it first, you might see a dialog box like this. Outside of dialog boxes, command buttons vary in appearance. If a button changes into two parts when you point to it, you've discovered a split button. Clicking the main part of the button performs a command, whereas clicking the arrow opens a menu with more options. Option buttons Option buttons allow you to make one choice among two or more options. They frequently appear in dialog boxes. The following picture shows two option buttons. The "Color" option is selected. Check boxes 47 Check boxes allow you to choose multiple options at the same time. Click an empty check box to select that option To use check boxes: Click an empty square to select that option. A check mark will appear in the square, indicating that the option is selected. To turn off an option, clear (remove) its check mark by clicking it. Options that currently can't be selected or cleared are shown in gray. Sliders : A slider lets you adjust a setting along a range of values. To use a slider, drag the slider toward the value that you want. A slider along the bar shows the currently selected value. In the example shown above, the slider is positioned midway between Slow and Fast, indicating a medium pointer speed. Text boxes: A text box allows you to type information, such as a search term or password. The following picture shows a dialog box containing a text box. We've entered "bear" into the text box. Text boxes that require you to enter a password will usually hide your password as you type it, in case someone else is looking at your screen. Drop-down lists: Drop-down lists are similar to menus. Instead of clicking a command, though, you choose an option. When closed, a drop-down list shows only the currently selected option. The other available options are hidden until you click the control, as shown below. To open a drop-down list, click it. To choose an option from the list, click the option. 48 List boxes: A list box displays a list of options that you can choose from. Unlike a drop-down list, some or all of the options are visible without having to open the list. To choose an option from the list, click it. If the option you want isn't visible, use the scroll bar to scroll the list up or down. If the list box has a text box above it, you can type the name or value of the option instead. Tabs : In some dialog boxes, options are divided into two or more tabs. Only one tab, or set of options, can be viewed at a time. The currently selected tab appears in front of the other tabs. To switch to a different tab, click the tab. Whenever you open a program, file, or folder, it appears on your screen in a box or frame called a window. Parts of a window Although the contents of every window are different, all windows share some things in common. For one thing, windows always appear on the desktop—the main work area of your screen. In addition, most windows have the same basic parts. Parts of a typical window Title bar. Displays the name of the document and program Minimize, Maximize, and Close buttons. These buttons hide the window, enlarge it to fill the whole screen, and close it, respectively Menu bar. Contains items that you can click to make choices in a program. Scroll bar. Lets you scroll the contents of the window to see information that is currently out of view. 49 Borders and corners. You can drag these with your mouse pointer to change the size of the window. Changing the size of a window To maximize window, click its Maximize button or double-click the window's title bar. To return a maximized window to its former size, click its Restore button or, double-click the window's titlebar. To resize a window (make it smaller or bigger), point to any of the window's borders or corners. When the mouse pointer changes to a two-headed arrow (as in picture), drag the border or corner to shrink/enlarge the window. Drag a window's border or corner to resize it. Minimizing a window: To minimize a window, click its Minimize button. The window disappears from the desktop and is visible only as a button on the taskbar, the long horizontal bar at the bottom of your screen. To make a minimized window appear again on the desktop, click its taskbar button. The window appears exactly as it did before you minimized it. Closing a window Closing a window removes it from the desktop and taskbar. To close a window, click its Close button. The taskbar provides a way to organize all of your windows. Each window has a corresponding button on the taskbar. To switch to another window, just click its taskbar button. The window appears in front of all other windows, becoming the active window—the one you're currently working in. To easily identify a window, point to its taskbar button. 50 When you point to a taskbar button, you'll see a thumbnail-sized preview of the window. This preview is especially useful if you can't identify a window by its title alone. Dialog boxes: A dialog box is a special type of window that asks you a question, allows you to select options to perform a task, or provides you with information. Most dialog boxes can't be maximized, minimized, or resized. They can be moved. Working with files and folders A file is an item that contains information. On your computer, files are represented with icons; this makes it easy to recognize a type of file by looking at its icon. Here are some common file icons: An empty folder (left); a folder containing files A folder is a container you can use to store files in. If you had thousands of paper files on your desk, it would be nearly impossible to find any particular file when you needed it. That's why people often store paper files in folders inside a filing cabinet. Folders can also store other folders.You can create any number of subfolders, and each can hold any number of files and additional subfolders. 51 Understanding the parts of a window When you open a folder or library, you see it in a window. The various parts of this window are designed to help you navigate around Windows or work with files, folders, and libraries more easily. Here's a typical window and each of its parts: Window part What it's useful for Navigation Use the navigation pane to access libraries, folders, saved searches, and pane even entire hard disks. Use the Favorites section to open your most commonly used folders and searches. You can also expand Computer to browse folders and subfolders. Back and Use the Back button and the Forward button to navigate to other Forward button folders or libraries you've already opened without closing the current window. These buttons work together with the address bar; after you use the address bar to change folders, you can use the Back button to return to the previous folder. Toolbar Use the toolbar to perform common tasks, such as changing the appearance of your files and folders, burning files to a CD, or starting a digital picture slide show. The toolbar's buttons change to show only the tasks that are relevant. Address bar Use the address bar to navigate to a different folder or library or to go back to a previous one. Library pane The library pane appears only when you are in a library (such as the Documents library). Use the library pane to customize the library or to arrange the files by different properties. 52 Column Use the column headings to change how the files in the file list are headings organized. File list This is where the contents of the current folder or library are displayed. If you type in the search box to find a file, only the files that match your current view (including files in subfolders) will appear. Type a word or phrase in the search box to look for an item in the current Search box folder or library. The search begins as soon as you begin typing—so if you type "B," for example, all the files with names starting with the letter B will appear in the file list. Details pane Use the details pane to see the most common properties associated with the selected file. File properties are information about a file, such as the author, the date you last changed the file, and any descriptive tags you might have added to the file. Preview pane Use the preview pane to see the contents of most files. If you select an e-mail message, text file, or picture, for example, you can see its contents without opening it in a program. If you don't see the preview pane, click thePreview pane button in the toolbar to turn it on. Viewing and arranging files and folders When you open a folder or library, you can change how the files look in the window. For example, you might prefer larger (or smaller) icons or a view that lets you see different kinds of information about each file. To make these kinds of changes, use the Views button in the toolbar. Each time you click the left side of the Views button, it changes the way your files and folders are displayed by cycling through five different views: Large Icons, List, a view called Details that shows several columns of information about the file, a smaller icon view called Tiles, and a view called Content that shows some of the content from within the file. Windows Applications – Notepad, WordPad, Paint ,Calculator. Start/Accessories menu is used to access convenient tools (application programs) included in Windows XP that can be used to perform many everyday tasks. Notepad Notepad is a text editor, which is a program similar to a word processor but cannot perform any special editing. No embedded codes are inserted into the document. Text files also called: unformatted text files and ASCII (American Standard Code for Information Interchange). 53 With Notepad, you can: Create simple text documents Multi-tasking/create/edit batch files Print a file Formatting with Page Setup and Printing in Notepad To print a Notepad document, you can locate the document with Explorer or My Computer. Open the file. Print file by using: File/Print command from the menu bar. Select Print from the shortcut menu that comes up when you right-click the file. Can also drag and drop to a printer shortcut. You can also open Notepad first and then open the document from Notepad’s File/Open command. Once the document is opened you can print it. Advantage of opening Notepad prior to locating file: Can apply page formatting before you print. Can add a header or footer. Can adjust the margins. 54 Features of Notepad: 1. Notepad has minimal editing features. 2. Notepad has word wrap which prevents text from running over into the margins and automatically moves text to the next line. 3. Used to create/save/open/edit file. 4. Can create time log. 5. Within Notepad – cut, copy, and paste text. 6. Copy data to Notepad from other files. 7. Copy Notepad text to other word processing text or database document. WordPad WordPad is a simple word processor. WordPad allows simple formatting: Change fonts. Character level formatting. Margins can be changed/created. Insert bulleted charts/graphic and sound files. Has menu bar and toolbar. WordPad lacks the powerful features of other word processors such as creating columns, tables, and spell checking. You do not need to press when you reach the right margin. Word processors will move to the next line automatically. This is called a soft return. The only time you need to press is to create a new paragraph. This is called a hard return. Paragraphs: Traditional English style paragraph includes a topic sentence, supporting sentences, and a concluding sentence. Indented by one tab. A paragraph, in word processing terms, is all the text between paragraph marks (¶). It can be one character, one page, or several pages of text. To indent a paragraph you use the key. 55 Features of WordPad: Title bar/Name of document first (docucentric approach) Menu Bar Toolbar Format Bar Document Ruler Selection Bar: unmarked column along left edge of document window. Insertion Point: is where you begin keying in text. 2 modes – Insert mode (Default) and Typeover -Press Insert to toggle between modes. Status Bar: tells you the status of the document. WordPad and Microsoft Word both claim.RTF extension. Rich text format (RTF) allows the exchange of text files between different word processors in different OS. Problems can occur when any registered file extension is claimed by more than one program. The default extension for WordPad documents is.doc. This extension is also used by Word for Windows, so if Word is installed, a document you create in WordPad might not open with WordPad when you double-click it. Editing a Document in WordPad To edit text you need to move the insertion point to the correct position. You can move the insertion point with either the mouse or the keyboard. The keyboard is usually used for keying in data. The mouse is usually used for editing. There are several key combinations that can be used to quickly move the insertion point. The Format Toolbar offers shortcuts to menu commands. Formatting Paragraphs and Using Tabs : You can change paragraph alignment so that it is left-justified, centered, or right-justified. Left-aligned or left-justified means that the selected paragraph(s) will line up on the left margin. Right-aligned or right-justified means that the selected paragraph(s) will line up on the right margin. Centered means that each line in the paragraph(s) will be centered between the left and right margins. The first line of a paragraph can be indented by pressing the key. The key moves the first line a preset number of spaces from the left margin. Printing and Page Setup in WordPad You can use the same techniques to print a document from WordPad that you used to print a document from Notepad. In WordPad, the only formatting that you can apply to the document (Page Setup) is to alter the margins. Headers and Footers are not supported Paint Paint is a graphics application program used to create drawings or images. Can only create/edit bitmap graphics (.bmp) Bitmap Graphics: Screen divided into pixels (pels) Drawing = turning pixels on or off in different colors Detailed Take up lots of disk space Resolution is fixed 56 If installed programs (such as Office) have correct graphic filters, Paint can read TIFF, JPEG, GIF, PCX, Targa and Kodak Photo CD files. Save Paint files in GIF and JPEG format. Images created can stand alone or be copied to other documents. Graphics files are identified by file extensions. 57 Paint Window The Paint window has many components, some are common to all windows programs, others are not. 1. Menu Bar – location of choices consistent: Choices available depend on program’s purpose. Paint choices different than word processing – task different. New choice – Image. 2. Tool Box - is actually a toolbar that you select your drawing tools from. Below the Tool Box is an area called the Tool Options box where the options available for the selected tool are displayed. 3. Color Box - contains the colors you can use in Paint. The foreground color is the color you draw with. The background color is the color of your drawing area. 4. Drawing area - is like a canvas and is the area where you draw. Default drawing tool – pencil. Cursor assumes shape of selected drawing tool. The Tools: 1. Free-Form Select – Selects a free form cutout in a drawing. 2. Select – Selects a rectangular cutout. 3. Erase/Color Eraser – Changes the foreground color to the background color. 4. Fill With Color – Fills a bordered area with the selected foreground color. 5. Pick Color – Picks a color in your drawing and uses it as your foreground color or background color. 6. Magnifier – Magnifies a selected area. 7. Pencil – Creates a free-form line. 8. Brush – Draws a free-form brush stroke. 9. Airbrush – Creates a spray can effect. 10. Text – Places text in the drawing. 11. Line – Draws a straight line. 12. Curve – Draws a straight line, then curves it. 13. Rectangle – Creates a rectangle or square. 14. Polygon – Draws a shape with an unlimited number of sides. 15. Ellipse – Creates a circle or ellipse. 16. Rounded Rectangle – Creates a round-cornered rectangle or square. 58 Fill Styles: When you select a shape tool, three choices appear in the Tool Options area. Each of these choices is a fill style. The effect of each of the fill styles depends on the mouse button used to draw the shape. Using the Left mouse button: Top: Outline in foreground color. No fill color. Middle: Outline in foreground color. Fill in background color. Bottom: Solid shape in background color. Has no outline. Using the Right mouse button: Top: Outline in background color. No fill color. Middle: Outline in background color. Fill in foreground color. Bottom: solid shape in foreground color. Has no outline. Picture Characteristics Paint used to view existing picture. Paint can be used to create a new picture. Standard settings for new picture. Creates picture with default settings. You can change these default settings. The Shape Tools The Shape tools let you work with pre-defined shapes unlike the free-form tools. Shape tools include Rectangle, Ellipse, Polygon, and Rounded Rectangle. Less color means a smaller file. Importing and Exporting Graphics To import is to bring a drawing into your picture from a graphic file. To export is to save to file a graphic image. Clip art is a collection of many, usually small, images that you can add to your graphics. Clip art can be purchased. Can alter clip art and save it as new drawing. Using Text and Other Pictures in a Drawing You can also add text to your pictures. You can choose different fonts and styles for your text line in a word processor. Characters from the font Wingdings can be imported to add pictures to your drawing. Printing in Paint You can print any picture that you create or view in Paint. Graphics take much longer to print than text and the quality of the printout will depend on the quality of the printer. If the printer is not a color printer, the picture will print in shades of gray. Using Drawings as Background Any drawing you create in Paint can be used as desktop background. 1. Using Windows XP Calculator Like a calculator you keep in a desk drawer, the Windows Calculator is small but saves you time by performing all the calculations common to a standard calculator. The Standard Windows Calculator, works so much like a pocket calculator that you need little help getting started. 59 To display the Calculator, open the Start menu and choose Programs, Accessories, Calculator. The Calculator opens in the same view (Standard or Scientific) in which it was displayed the last time it was used. To close the Calculator, click the Close button in the title bar. If you use the Calculator frequently, however, don't close it; click the Minimize button to minimize the Calculator to a button on the taskbar. The Calculator has only three menus: Edit, View, and Help. The Edit menu contains two simple commands for copying and pasting; the View menu switches between the Standard and Scientific views; and the Help menu is the same as in all Windows accessories. 2.Operating the Calculator To use the Calculator with the mouse, just click the appropriate numbers and sign keys, like you would press buttons on a desk calculator. Numbers appear in the display window as you select them, and the results appear after the calculations are performed. To enter numbers from the keyboard, use either the numbers across the top of the keyboard or those on the numeric keypad (you must first press the NumLock key if the NumLock feature is not enabled). To calculate, press the keys on the keyboard that match the Calculator keys. 60 3 Introduction to Business Communication Tools Introduction Microsoft Office is a collection of different application programs that were originally designed to be used to perform many of the tasks that are completed every day in an office setting, but they can also be useful in your personal life as well. Microsoft Word is a word processing program that can be used to type documents, from simple letters to illustrated newsletters. Microsoft Excel is a spreadsheet program that can be used to track of lists, numbers and statistics, such as might be used in accounting. Microsoft Access is a database program that can be used to track of diverse but related information, such as customer orders, customer billing information, customer shipping information, and product inventories. Microsoft PowerPoint is presentation software that can be used for making fully animated computer presentations. Microsoft Publisher is publication design software that can be used for creating greeting cards, business cards, calendars and more. 3.1 Microsoft Word 1. Introduction A word processor is a type of computer program that is used to create a variety of documents, from simple letters to fully illustrated newsletters and fliers. Word Processing applications display text on a computer screen and allow users to easily add, remove, and change the style, size, and placement of text in a document without having to retype the entire document as they would with a typewriter. Microsoft Word is one of the most popular word-processing software applications in use today. 2. Starting MS-Word 2007 Opening Microsoft Word To open Word, do either one of the following: Click once on the Start button on the bottom left corner of the screen. Click on Programs. Move the cursor to the new menu on the right and then click on Microsoft Office 2007. Move the cursor to the next menu that opens and click Microsoft Office Word 2007. A blank document will appear on the screen. Main screen of a Microsoft Word 2007 Document The screenshot below is the opening screen for Microsoft Word 2007. Here we will review screenshots and documentation on how to navigate some of the basic menus and the steps necessary to format a basic paper correctly. 61 Page Setup and Margin Formatting The screenshot below displays the menu path to change the margins in a paper. According to APA, all margins are set at 1 inch. 1. From the menu tab at the top of Word, select Page Layout. 2. In the Page Layout menu, the margins button will allow you to change the margins to the correct format. 62 3. Select Normal to set all margins to one inch. Formatting Font The screenshot below displays the menu path to change the font. Use a traditional font such as Times New Roman or Courier in 12-point size. 1. Select the Home tab. 2. From the Font menu, you may adjust the font, style, and size to the correct format. Formatting Spacing The standard spacing format for a paper is double-spacing. Double-space the entire document, including the reference page. The screenshot below displays the menu path to change the spacing format to double. 63 1. Select the Home tab. 2. From the Paragraph menu, you may adjust the line spacing from the Line Spacing dropdown menu. (Note: Word 2007 places extra space between paragraphs. You will need to adjust this by selecting the Page Layout menu. Then access Paragraph and Indents and Spacing. Under the Spacing heading, set the spacing option to 0 pt. before and 0 pt. after. Click OK.) Page Headers Identify each page with the first two or three words of the title and with the page number placed on the upper right hand corner of the page. Use five spaces between the title and the page number. Do not use your name to identify each page. Be sure the font type and size are the same as that used in the document. To create a correct APA header with a page number in Word 2007, use the following guidelines: 1. Click on the Insert tab. 2. Click on the Header tab. 1. Click on the Blank header tab from the drop-down menu. This will put the curser inside the header. 2. Click on the Page Number tab. 3. Place the curser on the drop-down menu over Top of Page to bring up another drop-down menu. 4. Click on Plain Number 3 on the drop-down menu (the third choice). This will place a page number inside the header at the right margin. 5. Type the portion of the title to go in the header and add five spaces. Your header is complete. 6. Click on Close Header and Footer on the far right. 64 Hanging Indent Select the text that requires a hanging indent OR create a hanging indent before typing the text. From the Home menu, click on the Paragraph command (see Picture One). This will bring up the Indents and Spacing tab (see Picture Two). Under Indentation in the Special box, click on Hanging and OK. 65 Centering Text The screenshot below is an example of text that is centered and that is not centered. In order to center text highlight the text that requires centering and select the icon in the formatting toolbar as shown. 1. Select the Home tab. 2. Highlight the text to be centered. 3. Click the button to center the text on the Paragraph toolbar. 3.2 Microsoft Excel 1.Introduction to Microsoft Excel 2007 Microsoft Excel is a very powerful tool for you to use for numeric computations and analysis. Excel can also function as a simple database but that is another class. Today we will look at how to get starting with Excel and show you around the neighborhood sort of speak. 2. Starting MS-Word 2007 To start Microsoft Excel : Click once on the Start button on the bottom left corner of the screen. Click on Programs. Move the cursor to the new menu on the right and then click on Microsoft Office 2007. Move 66 the cursor to the next menu that opens and click Microsoft Office excel 2007. A blank document will appear on the screen. Main screen of a Microsoft Excel 2007 Document This is a workbook. A workbook is a collection of worksheets (spreadsheets) and macros. By default, Excel creates 3 worksheets in a new workbook. The worksheets are designated at the bottom part of the window where you see the file folder-like tabs. The tabs are named Sheet1, Sheet2, and Sheet3. If you click on Sheet2, you will be in Sheet2 and not Sheet1 so you need to be aware of which worksheet you are in. Office Fluent user interface In Excel 2007, the new Office Fluent user interface replaces the traditional menus and toolbars from previous versions of Excel with a single mechanism designed to help users find the right features more efficiently. The interface contains three main components; The Office Button, The Quick Access Toolbar, and The Ribbon. 67 Open a New Workbook Some times you have to create a new workbook. 1. Click on the Office Button 2. Click on New You are now able to open recently used or new workbooks from this panel. You can also open up templates that are available with Excel or ones that you create. If you click on Blank workbook, Excel will create a new workbook for you. 68 What are Columns, Rows, and Cells? Columns are the vertical markers in the worksheet and are denoted by the alphabet i.e. A, B, C. The rows are the horizontal markers in the worksheet and are denoted by numbers i.e. 1, 2, 3. Cells are the single box that you get where the column and row intersect i.e. A1, B3, and C2. You will often need to know the cell reference. The cell reference is the cell’s name and you can find that by looking at the toolbar. This means that the cell that is selected is named C28. selecting a cell 1. We are going to select C28. Look for the C column. 2. Look for the Row number 28. 3. You may use your finger to follow the column C down to where row 28 is. 4. Once you have located it, click on it. 5. Look at the toolbar; the cell reference box should say C28. If it does not, try again. 6. After you have done this, click on a different cell and note the cell reference box. selecting a

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