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Figure 3.76 : Themes of PowerPoint Click a style to select it. The new background will appear in the slides. NOTE : You can select Format Background from the menu to open a dialog box and make changes to the background color. 3.12.16 Pictures and ClipArt On each slide you create in your presentation, you have information you want to communicate with the audience. You can do this with text and illustrations, such as pictures and clip art. Inserting pictures Pictures and clip art can be inserted from the Ribbon, as well as by using the commands that appear in certain placeholders. In both methods, the image is centered in the middle of any selected slide placeholders. To insert a picture/clipart from the Ribbon: Figure 3.78 : Clip Art l Select the Insert tab. l Click the Insert Picture or Insert ClipArt command in the Illustrations group. The Insert Picture dialog box will appear. l Locate and select the picture you want to use. l Click Insert, and it will appear on the slide. To insert a picture / clipart from a placeholder command : l Click the Insert Picture / Insert ClipArt command in the placeholder. The Insert Picture dialog box will appear. l Locate and select the picture you want to use. l Click Insert, and it will appear on the slide. Modifying pictures Figure 3.79 : Placeholder to Insert Picture PowerPoint provides you with several commands that allow you to modify pictures. When you select a picture, a Picture Tools Format tab appears on the Rib- bon. To apply a picture style : l Select the picture. l Select the Format tab. l Click the More drop-down arrow to display all the picture styles. l Hover over each picture style to see a live preview of the style on the slide. l Click a picture style to apply it to the image. 91

To change the shape of a picture : l Select the picture. l Select the Format tab. l Click the Picture Shape icon. A menu appears. l Click a shape to select it. The shape of the picture will change on the slide. To add a border to a picture : l Select the picture. l Select the Format tab. l Click the Picture Border command, and select a color. To crop a picture To “crop” an image is to remove or adjust the outside edges of an image (typically a photo) to improve framing or composition, draw a viewer’s eye to the image subject, or change the size or aspect ratio. In other words, image cropping is the act of improving a photo or image by removing the unnecessary parts. l Select the picture. l Select the Format tab. l Click the Crop command in the Size group. The black cropping handles appear. l Click and move a handle to crop an image. Corner handles will crop the picture proportionally. l Click the Crop command to deselect the crop tool. Other picture tools There are many other things you can do to modify a picture. From the Format tab, other useful commands include : l Change Picture: Selects a new picture from your computer l Reset Picture: Reverts to original picture l Brightness: Adjusts the brightness of the picture l Contrast: Adjusts the contrast of the picture from light to dark l Recolor: Modifies the color in a variety of ways, including black and white, sepia, pink, and purple 3.12.17 WordArt and Shapes There are many features and commands you can use in PowerPoint Figure 3.80: WordArt to create visually appealing slides. Two of these features are WordArt and shapes. WordArt allows you to create stylized text with textures, shadows, and outlines. It can be applied to text on any slide. Additionally, in PowerPoint you can insert a variety of shapes such as lines, arrows, callouts, stars, and basic shapes, including rectangles and circles. 92

Working with WordArt To apply a WordArt style : l Select the text you want to modify. The Format tab will appear. l Select the Format tab. l Move your cursor over a WordArt style in the WordArt Styles group to see a live preview of the style on the slide. l Click the More drop-down arrow to see all possible WordArt styles. l Click an option to select it. To change the fill color of a WordArt style : l Select the text you want to modify. Figure 3.81: WordArt l Click the Text Fill command in the WordArt Styles group. fill color l Move your cursor over a color option to see a live preview on the slide. l Click a color to select it. OR select from the following : Ü No Fill : This option will leave the WordArt text without a fill color. Ü More Fill Colors : This opens a dialog box of color choices you can use as a fill color. Ü Picture : This opens the Insert Picture dialog box. From here, you can select a picture from your computer to use as the fill background. Ü Gradient : This displays a submenu of various gradient options that change how the fill color appears. Ü Textures : This displays a submenu of various textures you can apply to WordArt text. Working with shapes To insert a shape : l Select the Home tab. l Click the Shapes command. l Click a shape from the menu. l Move your cursor toward the slide. It will appear as a cross shape. l Click and hold down the mouse button, and drag the cursor until the shape is the desired size. l Release the mouse button to insert the shape. To change the shape fill : l Select the shape. The Format tab will appear. l Select the Format tab. l Click the Shape Fill command to display a drop-down list. l Select a color from the list, or choose one of the other menu options. Figure 3.82 : Shapes 93

To apply a shape effect : l Select the shape you want to modify. The Format tab will appear. Figure 3.83 : Shape effect l Select the Format tab. l Click the Shape Effects command. l Move your cursor over a menu option. A submenu will appear. l Move your cursor over an option in the submenu to see a live pre- view of the effect on the slide. l Click an option to select the shape effect. 3.12.18 Working of Tables The goal of most PowerPoint presentations is to communicate information to a person or group of people. The information can be communicated in various ways, such as through pictures, lists, or paragraphs of text. Another way is to use a table to organize the information. A table is a grid of cells arranged in rows and columns. To insert a table using a placeholder command : l Select the slide where you want to insert a table. l Click the Insert Table command in the placeholder. The Insert Table dialog box will appear. Figure 3.84 : Placeholder to Insert Table l Enter the number of table columns and rows in the dialog box. l Click OK. The table will appear on the slide, and the Design and Layout tabs will appear on the Ribbon. l Enter text into the table. About table styles and options When you insert a table, PowerPoint automatically applies a table style to the table. You can see the style options in the Table Styles group on the Design tab. PowerPoint apply a style based on the theme of your presentation. Figure 3.85 : Table Design To apply a table style : l Select the table. l Select the Design tab to access all Table Styles and Options. l Move your cursor over a table style in the Table Styles group to see a live preview of the style on the slide. 94

l Click the More drop-down arrow to see all available options. l Click a style to select it. 3.12.19 Working with Headers and Footers PowerPoint allows you to create headers and footers, that is, information that appears at the top and bottom of all slides. This information will typically include the name of the presenters, their affiliation, and the presentation title, slide number, and date, but other information can be added as well. The steps to insert header and footer are : l First, you need to access the INSERT tab and click on the Header & Footer button. l A dialog box will appear, as shown in the figure. l The first option available is Date and Time. If you select the Date and Time checkbox, you will be given two options : Update automatically and Fixed. Figure 3.86 : Header and Footer Ü The Update automatically option means that the date and time will updated every time you open the presentation, which will save you the time and effort involved in updating it manually. Ü The Fixed option means that, even if you open the presentation a month from now, the date and time will be fixed to the time when you created the header and footer. l The next two options are Slide Number and Footer. Ü It is usually a good idea to include the slide number so that it’s easier for you to refer back and forth to individual slides while you present. Ü If you select Footer, you will be given the chance to write up your own customized text. Usually this would be your name and affiliation. l The last option determines whether the header and footer is shown on the title slide. It is better not to show this information on this slide since most of that information will be al ready displayed, such as the title of the presentation, the name and affiliation of the pres- enter, and sometimes even the date. l Click Apply to All to save the changes and to update the slides. 3.12.20 Using Slide Master The easiest way to make the same change to all slides or slides that use a specific layout is to change the slide master, also called the master slide. A master slide is one that is a part of every presentation that controls certain text characteristics such as font type, size, and color, as well as background color and style. 95

Masters can affect all the slides in a presentation. There are masters that control the slide, notes pages, and handout pages. When you apply a template to a presentation, you apply a new set of masters that control the presentation’s look and format. Any changes you can make to a slide in Normal view can be made to the slide master so the change will be reflected on all slides in the presentation. There are three types of masters using in PowerPoint Types of Master Description Slide Master The Slide Master is an element of the design Handout Master template that stores information about the tem- plate, such as font styles, placeholder sizes and Notes Master locations, background design, and color schemes. The Handout Master is used to set the format- ting of your handouts pages. You can set head- ers, footers, and the size and positioning of the number of handouts per page. The Notes Master is used to set the formatting for your notes pages. You can set headers, foot- ers, and the Notes Body area To view the slide master : l Select the View tab. l Click any of the Master view command in the Presentation Views group. Figure 3.87 : Slide Master NOTE : If the Slide Master tab is active, click the Close Master View command to return to Normal view. 3.12.21 Watermark in PowerPoint A watermark is usually added to your content to protect it from unauthorized copying. You can insert a picture into your presentation and make it transparent. It will become a wa- termark that will overlap your slides when you are presenting them. In order to add one picture to all slides, use Slide Master. The steps to add a watermark are : l Open your presentation that you want to add a watermark to. 96

l Go to View and click Slide Master. l Switch to the Insert tab and click Shapes. Then select a rectangular form. l Right click on the shape and select Format Shape. l In the Format Picture window, choose Picture or tex- ture fill and browse for a picture File. l Select a picture that you want to attach from your computer and add it on the slide. l Resize the shape to conform to the picture’s dimensions or check the option Tile picture as texture to constrain the picture’s size and proportions. l Close the Slide Master View command to return to the Normal view. Figure 3.88 : Format Picture 3.12.22 Inserting Sounds and Movies Inserting Sounds PowerPoint allows you to add sound to your presentation in several ways. You can do this by using a sound file on your computer, choosing from hundreds of sounds available through the clip organizer, or playing tracks from an audio CD. Do you want the music to play through the entire presentation, or would you prefer the music only to play on one slide? PowerPoint not only allows you to use sound, but it also allows you to customize sound options so you can play the sounds you want, the way that you want. To insert a sound file from your computer : l Select the slide where you want to add sound. l Select the Insert tab. l Click the drop-down arrow on the Sound command in the Media Clips group. l Select Sound from File from the menu. The Insert Sound dialog box will appear. l Locate the sound file on your computer. l Select the file. Figure 3.89 : Media Clips l Click OK. A sound icon and a dialog box will appear. l Select Automatically or When Clicked. Automatically will start the sound automatically as soon as the slide appears in Slide Show view, while When Clicked will start the sound when you click. Sound options On the Sound Tools Options tab, there are several options you can control that determine how the sound is used in the presentation. These include : 97

l Preview: Listen to the sound that will play l Slide Show Volume : Change the volume to low, medium, high, or mute l Hide During Show : Hide or display the sound icon during the slide show l Loop Until Stopped: Have sound play until you stop it by clicking or advancing to the next slide. To delete the sound : l Select the sound icon. l Press the Delete key on your keyboard. Inserting Movies You may want to insert a movie into your PowerPoint presentation. You can insert a movie from a file on your computer or from the Microsoft Office clip organizer. In addition, PowerPoint gives you many options to define how the movie will operate in the presentation. To insert a movie from a file on your computer : l Select the slide where you want to insert the movie. l Select the Insert tab. l Click the drop-down arrow on the Movie command in the Media Clips group. l Select Insert a Movie from File from the menu. The Insert Movie dialog box will appear. l Locate the file you want to insert from your computer. l Click the file name. l Click OK. The movie will appear on the slide. The movie Tools Options tab and Picture Tools Format tab appear on the Ribbon when the movie is inserted. l A dialog box will appear. Click Automatically or When Clicked. Automatically will start the movie automatically as soon as the slide appears in Slide Show view, while When Clicked will start the movie when you click. Working with Movies To preview the movie : l Select the movie on the slide. l Select the Options tab. l Click the Preview command in the Play group. l Press the Preview command again to stop the movie before it finishes playing. To change the movie volume : l Select the movie on the slide. l Select the Options tab. l Click the Slide Show Volume command in the Movie Options group. l Select low, medium, high, or mute to change the movie volume. 98

Other options Click a box to select and deselect movie options on the Movie Tools Options tab. These options include : l Hide During Show l Play Full Screen l Loop Until Stopped l Rewind Movie After Playing 3.12.23 Grouping and rotating objects Sometimes you may want to group objects to make them easier to position on the slide. Instead of moving each object individually or using the align menu options to arrange objects on the slide, you can group multiple objects into one object. Moving one object is often easier and faster than moving multiple objects on the slide. To group objects : l Select the objects you want to group. Ü To select multiple objects, click and drag your mouse to form a selection box around the objects, then release the mouse button. Figure 3.90 : Grouping option l Sizing handles will appear around each selected object, and the Format tab will appear on the Ribbon. l Select the Format tab. l Click the Group command in the Arrange group. l Select Group from the menu. l The selected objects will become grouped into one object. This is indicated by the box with sizing handles that includes all selected objects. To move the grouped object : l Click and drag the object to a new location on the slide. The cursor will become a four-arrow cross. l Release the mouse button. To ungroup objects : l Select the grouped object you want to ungroup. The Format tab will appear on the Ribbon. l Select the Format tab. l Click the Group command in the Arrange group. l Select Ungroup from the menu. The grouped object will appear as separate objects. 99

3.12.24 Slide Transition and Animated Effects Animation refers to the movement and sound accompanying text or slides in your presentation. Using animation with your lists and slides can often add excitement to your presentation by dis- playing text at crucial moments and making smooth transitions between topics. You can use preset animations or customize the animation to achieve the desired result. Transition effects—or transitions as they are often called—are the movements you see when one slide changes to another in Slide Show view. Transition effects are different from animation effects. The term animation in PowerPoint refers to the movements of text and objects on the slide, while transitions refer to the movement of the slide as it changes to another slide. To apply a default animation effect : l Select the text or object on the slide you want to Figure 3.91 : Animation animate. l Select the Animations tab. l Click the Animate drop-down menu in the Anima- tions group to see the animation options for the selec -tion. The options change based on the selected item. l Move your cursor over each option to see a live pre- view of the animation on the slide. l Click an option to select it. Adding a Custom Animation By using the Custom Animations pane, you can have more control over your animations. There are more animations available through the Custom Animations pane, as well. To apply a custom animation effect : l Select the text or object on the slide you want to animate. l Select the Animations tab. l Click Custom Animation in the Animations group. The Custom Animation task pane will appear on the right. l Click Add Effect in the task pane to add an animation effect to the selected text or object. l Select Entrance, Emphasis, Exit, or Motion Path to display a submenu of animation effects for the category. Figure 3.91 : Animation Ü Entrance: Changes how the selected item appears on the page Ü Emphasis: Draws attention to the selected item while the slide is displayed Ü Exit: Changes the way the selected item disappears from the slide Ü Motion Path: Animates the selected item so it moves to a specific place on the screen l Select an animation effect to apply it. 100

l The animation will display on the selected item on the slide and will appear listed in the Custom Animation task pane. To remove an animation effect : l Select the text or object on the slide you want to modify. l Select the Animations tab. l Click Custom Animation in the Animations group. The Custom Animation task pane will appear on the right. l Select the animation in the Custom Animation task pane list, if it is not already selected. l Click Remove. The animation label will disappear from the slide and from the Custom Animation task pane list. To preview an animation effect : l Select the text or object you want to modify on the slide. l Select the Animations tab. l Click Custom Animation in the Animations group. The Custom Animation task pane will appear on the right. l Select the animation in the Custom Animation task pane list. l Click Play at the bottom of the task pane to see a preview of the animation in Normal view. OR l Click Slide Show to see the animation in Slide Show view. Press the Esc key to return to Normal view. Using Transition To apply a transition to one slide : l Select the slide you want to modify. l Select the Animations tab. Figure 3.93 : Transition l Locate the Transition to This Slide group. By default, No Transition is applied to each slide. l Click the More drop-down arrow to display all available transition effects. l Click a slide transition effect to apply it to the selected slide. NOTE : It may be tempting to use a different transition for each slide, but doing so may be distracting and appear unprofessional. You should use few slide transitions to provide consistency in your presentation. 101

To apply a slide transition to all slides : l Select the slide you want to modify. l Select the Animations tab. l Locate the Transition to This Slide group. By default, No Transition is applied to each slide. l Click the More drop-down arrow to display all transition effects. l Click a slide transition effect to apply it to the selected slide. l Click Apply To All to apply the transition to all slides in the presentation. To set slide transition sound : l Apply a slide transition effect to a slide. l Click the Transition Sound drop-down menu in the Transition to This Slide group on the Animations tab. l Select a sound to apply it to the selected slide. To remove a slide transition effect : l Select the slide you want to modify. l Select the Animations tab. l Click No Transition in the Transition to This Slide group. 3.12.25 How to Start a PowerPoint 2007 Slide Show? A slide show may be a presentation of images purely for their own visual interest or artistic value, sometimes unaccompanied by description or text, or it may be used to clarify or reinforce information, ideas, comments, solutions or suggestions which are presented verbally. 1. Click the Slide Show button located (along with the other View buttons) in the lower-right corner of the screen. 2. Click the mouse, or press Enter, the down arrow, Page Down, or the spacebar. 3. Alternatively, open the Slide Show tab on the Ribbon. 4. Click From Beginning or From Current Slide. Keywords learned in this chapter Presentation Slide Slide Master Slide Show Grouping Themes Animation Transition 102

EXERCISE 1. Fill in the blanks : 1. An electronic page in a presentation is called ____________ 2. New Slide button for inserting a new slide can be found on ____________tab. 3. In ____________ view, you can see all the slides in a presentation concurrently. 4. ________ is a special effect that allows to specify how to navigate from one slide to other. 5. The ____________ Animation enhance uses the flying effect on the text and character. 2. Multiple Choice Questions : 1. ___________ is the default file name for a PowerPoint presentation. (a) Untitled 1 (b) Book 1 (c) Presentation 1 (d) Document 1 2. File extension for a PowerPoint 2007 presentation is ___________ (a) .ptt (b) .pptx (c) .docx (d) .clsx 3. The custom animation can apply ___________ (a) Font work gallery (b) Gallery (c) Text (d) All of these 4. The entire presentation can be seen at a time in ___________ (a) Slide Show view (b) Outline vie (c) Normal view (d) Slide Sorter view 5. Special effects used to introduce slides in a presentation are ………………. (a) transitions (b) effects (c) custom animations (d) annotations 3. Answer the following : 1. Write down the name of default view in a PowerPoint presentation. 2. Differentiate between a presentation and a slide. 3. Write use of layouts in PowerPoint. 4. In PowerPoint 2007 under the Insert tab, there is a button named Text Box. What is the utility of this button? 5. Animation is a feature, which you can use in your presentation. What is the purpose of this feature? 6. Write three functions that can be performed in Slide Sorter view of a presentation. 7. How are Header and Footer useful? 8. Differentiate between Slide Transition and Custom Animation. 9. Explain the various views of a slide available in PowerPoint 2007. 103

INTRODUCTION 4CHAPTER TO INTERNET “We are all now connected by the Internet, like neurons in a giant brain.” - ” - Stephen Hawking In this chapter, we will discuss the basics of the internet. This includes topology of computer network, a brief history of the internet, different types of internet connections, search engine and sending and receiving of emails. 4.1 WHAT IS INTERNET The Internet has gained popularity and becomes an essential part of a day to day life. Through Internet, we can exchange information with each other very quickly. The term Internet is derived from ‘interconnection’ and ‘networks’. A network is a collection of two or more interconnected computers or such computing devices, which can share information. The Internet is nothing but the interconnection of worldwide computer networks, i.e. network of networks. It can be defined as a global network of over a million smaller heterogeneous computer networks. 4.2 STRUCTURE The internet has no central structure or a central governing body. Therefore, there is no central failure. It means if the connection between two computers is lost, information still can be delivered to the destination by finding another route. The geometric structure of how computers are connected to each other in a network is called topology. There are five types of topology – Mesh, Star, Bus, Ring, and Hybrid. In a mesh topology, each device is connected to every other device on the network through a direct one to one link. In this topology, a link only carries data for the two connected devices. 104

Figure 4.1: Mesh Topology Advantages of Mesh topology: 1. Failure of one link doesn’t affect other links and the communication between other devices on the network. 2. If there is a failure, it is easy to detect. 3. Because of the direct computer to computer link unauthorized access is not possible. 4. Less amount of data travers in internode links. Disadvantages of Mesh topology: 1. A large number of wires or connection mediums are required to connect each system. 2. For a large mess network number of I/O ports required in each computer is very high since each computer needs to be connected with others. 3. The addition of a new device is very difficult, as it needs to be connected with all existing devices. In star topology, there is a central device to which all other computers have to be connected. Instead of direct communication between computers, in a star topology, all computers have to communicate through the central device. If one computer wants to send data to another computer, it has to first send the data to the central device, and then the central device forward that data to the destination. There are different types of such central devices like HUB, Switch, Router, etc. 105

Figure 4.2: Star Topology Advantages of Star topology : 1. Less expensive because each device needs to connect with the central device only with a single link. 2. Easier to install and easily new computers can be added to the network. 3. Failure of one link isolates only one computer. 4. A failed link can be easily identified. Disadvantages of Star topology: 1. The central device is the single point of failure. If the central device fails, the entire net work will be failed. 2. The central device requires more attention because it is the central system of star topology. In a bus topology, there is a main cable and all the computers of the network are connected to this main cable through drop lines. Since all the data is transmitted over the main cable, there is a limit of drop lines so that the data do not overflow in the main cable. In a bus topology, there is a main cable and all the computers of the network are connected to this main cable through drop lines. Since all the data is transmitted over the main cable, there is a limit of drop lines so that the data do not overflow in the main cable. 106

Figure 4.3: Bus Topology Advantages of bus topology: 1. Easy installation, each computer needs to be connected with the main cable. 2. Fewer cables required than Mesh and star topology 3. Less maintenance is required as there is no central device. Disadvantages of bus topology: 1. Difficultly in fault detection. 2. Not scalable as there is a limit of how many nodes you can connect with the main cable so that the main cable does not overflow. In ring topology, each computer is connected with two more computers on both sides. This direct connection forms a ring, and therefore, it is known as ring topology. In ring topology two adjacent computers can communicate directly but, non-adjacent computers have to communicate through other computers in the ring. In this case, if the received data is intended for other device then the adjacent computer forwards this data until the intended computer receives it. Figure 4.4: Ring Topology Advantages of Ring Topology: 1. Easy to install. 2. No central device is required. Disadvantages of Ring Topology: 1. A link failure breaks the ring and thus fails the entire network. 2. Each device has to be active all the time, otherwise, data will not be forwarded by an inactive device. A combination of two or more topologies is known as hybrid topology. For example, a combination of star and ring topology is known as hybrid topology. 107

Figure 4.5:Hybrid Topology There are no straightforward advantages and disadvantages of hybrid topology. When we connect more than one heterogeneous existing networks, it becomes a hybrid topology. 4.3 CLIENT AND SERVER In computing terminology, both “client” and “server” refer to computers that are used for different purposes. A client machine and a server can be differentiated based on their use and behavior. A computer can be configured to behave like a server and the same computer can be configured to behave like a client. Normally, a client is a comparatively lower capacity computer that accesses a server through a network. For example, we can browse a website presents on a server from our client computers. On the other hand, a server computer is a higher capacity computer that can store a wide variety of resources. There are various types of servers, such as an application server, file server, web server, database server, print server, proxy server, etc. 4.4 PROTOCOL A network protocol is an established set of rules that determine how data is transmitted between different computers in a network. Protocols are like a common language for computers. It allows connected computers to communicate with each other, regardless of any differences in their internal processes, structure or design. There are different protocols for different types of services. Some commonly used protocols are- HTTP, HTTPS, FTP, SMTP, etc. 4.5 HISTORY OF THE INTERNET The first workable prototype of the Internet ARPANET (Advanced Research Projects Agency Network) came in the late 1960s. It was started by the U.S. Department of Defense. On October 29, 1969, ARPAnet delivered its first message. The first computer was located in a research lab at the University of California, Los Angeles and the second was at Stanford. ARPANET adopted TCP/IP in 1983, and from then other computer scientists began to form network of networks. This was the starting of the modern Internet. With the invention of the World Wide Web (WWW) in 1990, by Tim Berners-Lee, the internet appeared in a more recognizable form. 4.6 INTERNET CONNECTION Internet connection refers to the link of a device to the internet. It is provided by the Internet Service Providers (ISP). Reliance Jio, Airtel, BSNL are some popular ISP in India. An ISP can provide an internet connection to their consumers in different ways. There are two types of connections- wired and wireless. 108

4.6.1 Wired internet connection: In a wired connection, a wire is laid down from ISP’s server to the consumer’s computer. There are different types of wire for this purpose. Each type of wire has its limitation on data transfer rate and range. In Table 4.1 data transfer rate and range of different types of cable are shown. Data transfer rate indicates the amount of data we can transfer using the cable in one second. On the other hand, data transfer range indicates the maximum length of the cable that we can use to transfer data. Suppose the maximum transfer range of a cable is N meters, and we need to transfer data up to 5xN meters. In such situation a special device called “repeater” can be used between every N meter to extend transmissions so that the signal can cover longer distances. Twisted Pair Co-axial Cable Optical Fibre Cable Max Transfer Rate 10 Gbps 100 Mbps More than 100 Gbps Max Transfer Range 100 m 500 m 2 KM and farther Table 4.1: Properties of different types of cables DIAL-UP: Dialup is the oldest technology to provide an internet connection to consumers. It simply uses a phone line and a modem to convert the analog signals into digital signals and vice versa. The modem in calls the Internet Service Provider (ISP) and connects with a maximum speed of 56k per second. In this technology, the telephone line is used to transmit data and the line remains busy until the connection is closed. DIGITAL SUBSCRIBER LINE (DSL): Using DSL, users get high-speed internet access through existing telephone networks. The telephone and DSL modem can work at the same time. There are two main types of DSL technology -Symmetrical DSL and Asymmetrical DSL. Symmetrical DSL connections offer equal bandwidth for upload and download. But normally people download more information than they upload. Therefore, an asymmetrical DSL connection has more downstream bandwidth and less upstream bandwidth. In DSL connection, signal conversion from digital to analog and analog to digital is not required. INTEGRATED SERVICES DIGITAL NETWORK (ISDN): ISDN is a digital transmission system, which is used to transmit voice and data through a tele- phone line. In terms of speed, ISDN is slower than DSL but an ISDN connection is more convenient and faster than a dial-up connection. CABLE: Cable internet access is a form of broadband Internet access that uses the same infrastructure as cable television. This can be used in an area where cable internet providers are available. Cable internet providers share the main connection with the consumers using coaxial cable. 4.6.2 Wireless internet connection: In the wireless connection, ISP’s server is connected to the consumer’s computer using wireless technology. There are different types of wireless technology for this purpose. Each technology has its limitation on data transfer rate and range. 109

SATELLITE CONNECTION: Satellite Internet access is provided through communication satellites. Different ISP provide modern consumer-grade satellite Internet service to individual users through geostationary satellites that can offer downstream data speeds up to 506 Mbit/s. Satellite Internet generally requires three primary components: a satellite, a number of ground stations known as gateways that relay Internet data to and from the satellite via radio waves, and a small antenna called VSAT at the subscriber’s location. Wi-Fi: The (Wireless Fidelity) Wi-Fi technology uses a radio frequency signal to connect your devices to a Wi-Fi network. If the Wi-Fi network has internet connectivity, once your device is connected with the network you can access the internet from your device. A Wi-Fi network may be open or password protected. Normally an open Wi-Fi network accepts all new devices to be connected, but to connect to a password-protected Wi-Fi network you must know the password. The coverage of Wi-Fi signal is very from device to device. WiMAX: Worldwide Interoperability for Microwave Access (WiMAX) is a long-range system, covering many kilometers, that used to deliver Internet connection to consumers. WiMax Internet service is also known as 4G, WiMax Broadband, WiMax VOIP, WiMax VPN, Fixed Wireless Data, Fixed Wireless Broadband, or Fixed Wireless Internet. 4.7 BROWSER To browse a website, we need a web browser. It is a computer program with a graphical user interface for displaying and navigating between web pages. Some popular web browsers are- Google Chrome, Mozilla Firefox, Internet Explorer, Microsoft Edge, Safari, Opera, etc. 4.8 WORLD WIDE WEB (WWW) WWW is the network of server computers accessible through an internet connection. Web- pages and other web documents are the main accessible resources in www. The server in which these web resources are available is called a web server. These web resources are identified in the global computer network by Uniform Resource Locators (URLs, such as http://example.com/). The resources of the Web are transferred from a web server to a client computer via the Hypertext Transfer Protocol (HTTP) and can be accessed by users using a web browser. 4.9 WEBSITE A website is a collection of one or more web pages, images, audio/video files, databases, etc. stored in a web server. On a website, a user can navigate from one web page to another web page using hyperlinks. A hyperlink is nothing but a visible element in a web page encoded with a URL. 4.10 UNIFORM RESOURCE LOCATORS (URL) URL is one of the key concepts of the internet. It is the mechanism used by a browser to retrieve a web resource on the internet. A URL can uniquely identify a web resource. A URL is composed of some mandatory and some optional parts. Figure 4.6 gives an idea of the different components of a URL. 110

Figure 4.6: Components of URL 4.11 SEARCH ENGINE A search engine is a software system that is designed to carry out searches (Internet searches) for web components. Based on the textual search query a search engine search WWW for information. The search results are generally presented in different lines in the result section as shown in Figure 4.7. Each result maybe some web page link or image or videos or some other type of files. Figure 4.7: An example of Google search. 4.11.1 How Search Engine works: Search engines are very useful in our day to day life. In search engines we just need to enter our query in the search box and in most cases, results from the web are displayed in milliseconds. A search engine has three main functions- Crawl, Index, and Rank. Crawling is the discovery process in which search engines discover web pages. Indexing is the process of storing information about discovered web pages in the search engine’s database. When a user enters a query to search, the search engine searches in its database and may find multiple results. The ranking is the process of ordering the search result based on relevance. There are numbers of approaches to rank a search result. Different search engines may use different ranking approach. 111

4.11.2 What can be searched? Search engines are remotely accessible programs that allow you to searches keywords for in- formation on the Internet. A user can enter any text to search. Based on the information available in the search engine’s database, the most relevant contents appear as a result. Normally a search engine returns relevant web page addresses as a result. But in some search engines, there are options to search for photos, videos, news, geographic information, etc. Some popular search engines are- goog- le, bing, yahoo, etc. 4.12 ELECTRONIC MAIL It takes many days to send a letter by post. Email, short for “electronic mail,” is one of the most widely used features of the Internet which needs only a few seconds to deliver a mail. It is a method of exchanging messages, different types of files between people using electronic devices. To send and receive email user must have email ids. SMTP, POP, or IMAP protocols are used to send and retrieve emails from an email server. 4.12.1 Email Address: Email address is used to send and receive emails. An email address has two parts: a username and a domain name. The domain name is used to transport an email message to the host of the recipient’s mail system. Both parts are separated by the “@” symbol. There is a length limit of 64 characters in the username and 255 characters in the domain name. Email addresses are not case sensitive. That is [email protected] and [email protected] refers to the same email id. 4.13 COMPONENTS OF EMAIL SUBJECT: The subject is a description of the topic of the message and displays it in the list of emails. The subject has to be typed by the sender. There is no constrain on what to be the subject of an email. However subject line should express what the email is about so that the recipient can prioritize the email’s importance without having to open it. SENDER (FROM): This is the sender’s name and email address. Using only name it is may not be possible to iden- tify the actual sender. Because there may be multiple people with the same name. Therefore, it is important to verify the sender’s email address once you receive an email. DATE: The date and time the message was received. RECIPIENT (To): The email address of the recipient. There may be multiple recipients of an email. The maximum number of recipients you can add to an email varies from domain to domain. 112

CC: In an email, CC is the abbreviation for “Carbon Copy.” Before the invention of email, to create a copy of a letter a carbon paper had to be placed between the one you were writing on and the paper that was going to be your copy. Just like the physical carbon copy, in email CC is an easy way to send copies of an email to other people. BCC: BCC stands for “Blind Carbon Copy.” Just like CC, BCC is also a way of sending copies of an email to other people. The difference between CC and BCC is that in the case of BCC no recipient can see BCC email ids whereas in the case of CC each recipient can see all CC email ids. ATTACHMENT: An email attachment is a computer file sent along with an email message. One or more files can be attached to any email message, and be sent along with it to the recipient with a restriction of the size of total attachments. This is typically used as a simple method to share computer files. Figure 4.8: The basic Gmail interface. SEND AND RECEIVE EMAIL: To send and receive an email, a user must have an email id. Many email service providers allow creating email ids in their domain free of cost. Some popular email service providers are- Gmail, yahoomail, rediffmail, ProtonMail, Zoho Mail, etc. All email service providers provide a more or less similar interface to send and receive emails. Some important and common features of an email interface are- INBOX: An inbox is the main folder where your incoming email gets stored in. In many email systems when a user login to the email interface using a username and password the contents of the Inbox folder are displayed by default. If Inbox is not already selected, by clicking on the Inbox folder in the navigation area, (usually on the left side of the e-mail interface) emails can be listed. 113

COMPOSE: The compose window allows a user to compose an email. In this window, you can add the recipient’s email ids (TO, CC, BCC), the email subject, the body of the email, which is the message itself, and some attachments. After composing the email, from this window you can send the email. Once you click on “send”, the email will be sent to the recipient’s email ids. SENT: Sent or Sent items is a folder or area that stores all emails that were successfully delivered. Once an email appears in the sent folder, the email cannot be recalled or recompose. DRAFTS: This section contains all such emails, which are composed but not yet sent. Normally when a user starts composing an email and saves the email for compose later or leaves the compose window without sending the email, those emails appear under the “Draft” section of an email interface. To recompose such an email a user just needs to select the email in the “Draft” section and can continue in the compose window. SPAM: Spam is a section of the email interface where junk emails appear. Spam emails are unsolicited bulk emails with commercial, fraudulent, or malicious intent. Normally email service providers can filter spam emails and store them in the “Spam” section instead of the “Inbox” section of the email interface. However, a user also can mark a particular email address as spam or not spam. Once an email address is marked as spam, all emails from that email address will appear in the “Spam” section of the user. TRASH: The “Trash” or “Bin” section of an email interface contains all such emails that have been deleted by the user. In “Trash”, the emails get automatically erased after a predefined number of days. Normally the emails from “Trash” are automatically deleted after 30 days, but it may vary with email service providers. This method is used to clean some space in the email account. FILE ATTACHMENT: When a user sends an email, along with the email some files also can be sent to the recipients. Such files of an email are called attachments. There may be a limit set by email service providers on the number, size, and type of such attachments. Normally the file attachment button is available in the compose window of an email interface. 4.14 CHAT AND VIDEO CONFERENCING: Chat is nothing but messages sent through the internet in real-time. Chat messages may be a textual or multimedia conversation over the Internet. To chat the user must be logged in (online) to the chat server. Many websites allow users to chat. Some such websites are- www.7cups.com, airtime.com, www.chat-avenue.com, Google Hangouts, etc. 114

Figure 4.9: Google meet interface for video conferencing. Video conferencing is a live video-based meeting between at least two individuals in different geographic areas utilizing video-enabled gadgets. Video conferencing permits various individuals to meet and discuss from distance by sending audio, video, text, etc. in real-time through the internet. Some video conferencing websites are- zoom.us, meet.google.com, www.webex.com, etc. KEYWORDS LEARNED IN THIS CHAPTER Internet Computer Networks Topology Client Server Protocol ARPANET ISP WWW Hyperlink URL Search Engine Email Chat Video Conferencing 115

EXERCISE 1. Fill in the blanks: 1. The connection structure of a computer network is called __________. 2. Normally server computers are ____________ than client computers. 3. An organization who provide an internet connection to their consumers is called _____. 4. Based on _________ search results are ordered in a search engine. 5. The sent section of an email interface contain _________ emails. 2. Multiple Choice Questions : 1. A network switch is required to form A) Star Topology B) Mesh Topology C) Ring Topology D) Bus Topology 2. How many cables are required to form a mesh topology of 10 computers? A) 15 B) 100 C) 25 D) 45 3. Which of the following is not a protocol? A) HTTP B) HTTPS C) ISP D) FTP 4. how many repeaters are required to transfer data up to 400 meters using a twisted-pair cable? A) Not Required B) 4 C) 2 D) 3 5. Normally unsolicited bulk emails appear in A) Inbox B) Trash C) Drafts D) Spam 3. Short answer questions: 1. What is topology? From your understanding describe which topology will be best to set up a computer network in your school. 2. Give an example of a URL and describe different sections of it. 3. What is ranking? How is it related to a search engine? 4. What is the use of BCC in an email? Describe with an example. 5. What are the differences between Chat and Video Conferencing? 116

ETHICS IN IT 5CHAPTER “Technology must be guided and driven by ethics if it is to do more than provide new toys for the rich.” -Freeman Dyson In this chapter, we will study the ethical issues arising out of the use and development of electronic technologies. 5.1 INTRODUCTION TO INFORMATION TECHNOLOGY In different section Information Technology define by Information Technology Association of America (ITAA) as “the study, design, development, implementation, support or management of computer based information systems, particularly software applications and computer hardware.” In today world it has huge effect in the human life; everything that is done has been done electronically such as making notes, report making, record of daily transaction etc. Not only in business sector but in day-to-day life it has an adverse affect. Even in the government sector almost all the thing is done by using technology. Even in the transportation, factory it is being used. Since it has developed so fast and drastically it is difficult to say that what and when changes will happen in next technology is difficult to say. Even in terms of computer and machineries things like mobile has gone smaller in size, has gone much faster, and in top of it internet has make huge changes in IT. 5.2 ETHICS IN INFORMATION TECHNOLOGY In the era of the Information Technology, IT has become one the life changing matter in medicine, transportation, banking sector, government sector, security, research sector and so on. Similarly it has affected both direction in right and wrong in aspect of community life, education, freedom, relationship, age, law and so on. As a part of IT, Internet has made big impact in revolution of global communication. Internet has opened the door for people to share lots of things such as find and share views in internet, find much information in web. It has given the facility for online shopping, online grocery where everything can be found, all we have to do is add in basket and pay after finishing shopping. 117

Now a day’s most of the bank has given online facilities so that one can manage their daily transac- tion by sitting in a room. Due to this reason it has gone so far that it has created conflict in different cultural. The advancement of technology makes it possible for unethical and criminal activities to be carried out in a more sophisticated way. So, it is necessary to have the knowledge of security issues, privacy issues and main negative impacts of IT. To deal with these issues in IT society it is important to find out the ethical issues. Let us discuss some of the major ethical issues in computer world nowadays. 5.3 PLAGIARISM Plagiarism is the act of stealing someone’s ideas or works and passing them off as your own. This includes text, media, and even ideas. Whenever another person’s work is copied and republished without an appropriate reference or citation, it is considered plagiarism. While this makes it easier to access information than ever before, it also makes it easier to plagiarize other people’s work. All it takes is a simple copy operation to copy large amounts of text or images from another source. Plagiarism can take place intentionally or unintentionally in many forms, such as from deliber- ate cheating to accidentally copying from a source without acknowledgement. 5.3.1 Is Plagiarism a crime? Plagiarism is considered a violation of academic integrity and a breach of journalistic ethics. Generally, plagiarism is not in itself a crime, but like counterfeiting fraud can be punished in a court for prejudices caused by copyright infringement, violation of moral rights. 5.3.2 Types of Plagiarism: THERE ARE 4 COMMON TYPES OF PLAGIARISM: Direct Plagiarism: That happens when you copy and paste complete sentences or paragraphs written by someone else, without attributing them or including quotation marks. Mosaic Plagiarism: This form of plagiarism occurs when a writer lifts phrases without using quotation marks or replaces certain words with their synonyms to maintain the original structure and meaning of the text. Self-Plagiarism: This form of plagiarism is more rampant in research-focused settings. Where a student submits a term paper or thesis by using his previous works in bits and pieces, and without getting permission from all the professors in volved. Accidental Plagiarism: As the name suggests, this form of plagiarism happens by accident. For example, if you forget to cite or misquote your sources, or paraphrase a full section from an other magazine without attributing it, you have committed plagiarism. 118

5.3.3 Why should you avoid plagiarism? At its core, plagiarism is an ethical issue. A writer who submits plagiarized work is committing theft with the hope of benefiting from that theft. This is true whether you’re turning in a school paper to get an “A” or are a writer by trade expecting monetary compensation. To avoid plagiarism, you should be following the guidelines given below; l Cite your source: When working to an idea or wording that’s not your own, add a citation in your writing that identifies the full name of the source, the date it was published, and any other citation element. l Include quotations: If you insert a source’s words into your writing, one of the most simple yet obvious ways to avoid plagiarism is by using quotation marks around the text to denote that the words aren’t your own. l Paraphrase The Right Way: Paraphrasing is rewriting a source’s ideas or information into your own words, without changing its meaning. But be careful—paraphrasing can slip into plagia- rism if done incorrectly. l Present your own idea: Instead of parroting the source’s ideas or words, explore what you have to say about it. Ask yourself what unique perspective or point you can contribute in your writing that’s entirely your own. 5.4 INTELLECTUAL PROPERTY RIGHTS Property is anything for you. You have rights over your property. It is protected by law. Simi- larly, ideas and thinking produced by mind are also protected by law. It is illegal to use them without the permission of the owner. Intellectual property is defined as any work that is creative and includes inventions, literary works, images, and symbols. With the introduction of the Internet, laws surrounding intellectual properties have changed significantly. In other words, these are the rights of the owner of informa- tion to decide how much information is to be exchanged, shared or distributed. The three types of laws that protect intellectual property are copyrights, trademarks, and patents. The creator of the information is the real owner of the information. And the owner has every right to protect his / her intellectual property. To protect one’s intellectual property rights one can get information copyrighted or patented or use trademarks. COPYRIGHT © You must have seen this © symbol, C enclosed within a circle, on different items, book, mag- azines and even web pages. This symbol generally comes before a statement, All Rights Reserved. This symbol shows that the materials and informations are copyrighted, and are the sole property of the owner. It is unlawful and unethical to use them without the permission of the owner. 119

TRADEMARKS A trademark is a distinctive sign that identifies certain goods or services produced or provided by an individual or a company. Trademarks may be one or a combination of words, letters and numerals Trademark protection ensures that the owners of marks have the exclusive right to use them to identify goods or services or to authorize others to use them in return for payment PATENT A patent grants monopoly for the exploitation of an invention. The holders of patent are granted the exclusive right to prevent others from using, commercializing or importing the patented products or processes. 5.5 SECURITY AND INTEGRITY OF INFORMATION Integrity means that data is protected from unauthorized changes to ensure that it is reliable and correct. Availability means that authorized users have access to the systems and the resources they need. Computer security includes procedures and techniques that are designed to protect a computer from accidental or intentional theft, unauthorized access or manipulation. It is both an individual and an organizational concern. Such damages may include loss of revenue, valuable data loss, productivity loss, and many more which may even lead to bankruptcy. 5.6 NETWORK SECURITY Network security is the security provided to a network from unauthorized access and risks. It is the duty of network administrators to adopt preventive measures to protect their networks from potential security threats. Computer networks that are involved in regular transactions and communication within the government, individuals, or business require security. The most common and simple way of protecting a network resource is by assigning it a unique name and a corresponding password. 5.7 FIREWALLS A firewall is a network security system that manages and regulates the network traffic based on some protocols. A firewall establishes a barrier between a trusted internal network and the internet. Most personal computers use software-based firewalls to secure data from threats from the in- ternet. Many routers that pass data between networks contain firewall components and conversely, many firewalls can perform basic routing functions. Firewalls are commonly used in private networks or intranets to prevent unauthorized access from the internet. Every message entering or leaving the intranet goes through the firewall to be examined for security measures. 5.8 ANTIVIRUS An antivirus is a tool that is used to detect and remove malicious software. It was originally designed to detect and remove viruses from computers. Modern antivirus software provide protection not only from virus, but also from worms, Trojan-horses, adwares, spywares, keyloggers, etc. 120

5.9 INTERNET SECURITY Internet security deals largely with the transit of information. For example, imagine you send an email, and while that message is in transit, a third party sweeps in and takes it before the message is delivered to its intended recipient (i.e., man-in-the-middle attack). Such hijackings are just one of many examples of crimes regarding the Internet. In such a case encryption serves as one method of defense, making any stolen information significantly less valuable to the doer. In particular, Secure Sockets Layer (SSL) and Transport Layer Security (TSL) are forms of encryption and authentication commonly used by business for their online platforms. 5.10 PASSWORD SECURITY Passwords provide the first line of defense against unauthorized access to your computer and personal information. The stronger your password, the more protected your computer will be from hackers and malicious software. You should maintain strong passwords for all accounts on your com- puter. Password is the key or secret word which is used to protect your information from an unau- thorized access. It is used for authentication and to prove your identity for accessing resources. GUIDELINES FOR MAINTAINING GOOD PASSWORDS:  Use at least 8 characters—the more characters, the better.  Use a mixture of both uppercase and lowercase letters.  Use a mixture of letters and numbers.  Include of at least one special character, e.g., ! @ # ?  Change the password regularly.  Avoid using the words from dictionary. 5.11 USERS’ PRIVACY Privacy is an important aspect of life. It is a desirable condition or a moral right that the person has, in relation to another person, or with respect to the possession of information by other persons about him or herself. It is unethical to infringe in the privacy of other people without the consent of the person. 5.12 CYBERCRIME Cybercrime is criminal activity that either targets or uses a computer, a computer network or a networked device. Most, but not all, cybercrime is committed by cybercriminals or hackers who want to make money. Cybercrime is carried out by individuals or organizations. The people who are associated with computer crimes are often called Hackers, Crackers, Virus Programmers, Information Warrior etc. They practice unlawful and illegal activities related to computer systems. 121

A hacker is a person who breaks into a computer system to get illegal access to the information stored there. A hacker may not cause any harm to the system or organization, but hacking is still illegal and unethical. A cracker is a person who breaks into a computer system just like a hacker, with the intension to steal passwords, files or programs for unauthorized use. Cracking is the act of breaking into a computer system, often on a network maliciously, for personal gain. 5.12.1 How to protect yourself against cybercrime:  Keep software and operating system updated  Use anti-virus software and keep it updated  Use strong passwords  Never open attachments in spam emails  Do not give out personal information unless secure  Be mindful of which website URLs you visit  Keep an eye on your bank statements 5.13 SOFTWARE PIRACY Software piracy is the act of stealing software that is legally protected. This stealing includes copying, distributing, modifying or selling the software. The majority of software today is purchased as a single-user license, meaning that only one computer may have that software installed on it at one time. Copying that software to multiple computers or sharing it with your friend without multiple licenses is considered software piracy, which is illegal. NOTE: A user who participates in software piracy is often referred to as a pirate or software pirate. 5.13.1 Types of Software Piracy: SOFTLIFTING: The most common type of piracy, softlifting, (also called softloading), means sharing a program with someone who is not authorized by the license agreement to use it. A common form of softlifting involves purchasing a single licensed copy of software and then loading the software onto several computers, in violation of licensing terms. This often occurs in business or school environments and is usually done to save money. HARD DISK LOADING: Hard disk loading is a type of commercial software piracy in which someone buys a legal ver- sion of the software and then reproduces copies or installs it onto computer hard disks. The person then sells the product. This often happens at PC resale shops and buyers aren’t always aware that the additional software they are buying is illegal. COUNTERFEITING: Counterfeiting means producing fake copies of a software, making it look authentic. This involves providing the box, CDs, and manuals, all designed to look as much like the original product as possible. Counterfeit software is usually sold at a discounted price in comparison to the legitimate software. 122

RENTING: Renting involves someone renting out a copy of software for temporary use, without the per- mission of the copyright holder. The practice, similar to that of renting a video from Blockbuster, violates the license agreement of software. END USER PIRACY: This occurs when an individual reproduces copies of software without authorization. These include:  Using one licensed copy to install a program on multiple computers  Copying discs for installation or distribution  Taking advantage of upgrade offers without having a legal copy of the version to be upgraded  Acquiring academic or other restricted or non-retail software without a proper license  Swapping discs in or outside the workplace In a nut shell, the objectives of computer ethic are to ensure the privacy and safety of the computer users, to helps people use the computer in the right way and to guarantee that the works that done by someone did not declare by other people. Therefore, we must follow all the ways to improve our ethics in order to achieve all the objectives as this issue really important in our daily life which are to protect our privacy, maintain our security and to respect others. However we are also encouraged to recognize the activities that follow computer ethics and also the activities that against computer ethics as a precaution in our life. Last but not least, computer ethics are very important for us to live comfortably and in peace hence we must do our part as computer users, obey all the computer ethics. Keywords learned in this chapter: Ethics Plagiarism Piracy Intellectual Property Rights Cyber crime Firewall Hackers Crackers 123

EXERCISE 1. Fill in the blanks: 1. Directly copying text, word for word is called _____________ 2. _____________ refers to attempts to gain information from otherwise undisclosed areas. 3. _____________ refers to the unauthorized duplication of computer software. 2. Multiple Choice Questions: 1. C in ICT stands for _____________. (a) Communication (b) Computer (c) Control (d) None of these 2. Making illegal copies of copyrighted software is called _____________ (a) Software piracy (b) Browsing (c) Collaboration (d) Electronic distribution 3. Purchasing of only one licensed copy of a software and distributing/loading it onto multiple systems is called as _____________ (a) Softlifting (b) Renting (c) Hard disk loading (d) Patent 3. Answer the following: 1. What are the main functions related to information? 2. Define the term plagiarism. 3. What is software piracy? What are its common forms? 4. Write down the major issues of security and integrity of information. 5. Name three types of law that can help restrict software piracy. 6. An extended synonym for Information Technology is ICT. So, how ICT differs from IT? 7. IT security today has become a major point of concern. What comes under IT security? 8. Elaborate the term software ethics. 9. Explain the need of protecting intellectual property right. 124

DATABASE PART I 6CHAPTER “You can have data without information, but you cannot have information without data.” – Daniel Keys Moran In this chapter, we will discuss about computer database and their importance. We will learn about the different components of a database. We will also learn why the uniqueness of data is important and how to design a simple relational database using different keys. 6.1 INTRODUCTION: We often heard the word “database”. But what does it exactly mean? A database is not only the collection of data or information. In the context of computer science, a database is a systematic collection of structured information or data, typically stored electronically in a computer system. In a database, data is organized in such a way that it can be easily accessed and managed. An online telephone directory is an example that uses a database to store data like name, phone numbers, and other contact details. There are different types of databases like Hierarchical, Relational, Object-Oriented, etc. out of which the Relational database is the most popular and widely used. Most of the time a database is accessed by a collection of programs called Database Management System (DBMS) that enable its users to search, insert, update and delete data. 6.2 NEED FOR A DATABASE: To understand the importance of a database we first need to understand the importance of data. Data are very important for an organization. For example, a school may have different types of data like student records, teacher records, library records, etc. These data are very important for the school. For example, without student records, a school cannot conduct an examination. Important data can be stored by maintaining multiple paper-based registers like an attendance register in a school or electronically in a computer. Storing data in registers have many disadvantages like it needs a large area to keep such registers, finding a record takes a very long time, etc. Therefore, it is better to store data electronically on computers. Electronic data can be stored either in files or in a database. Storing data in a database has several advantages over files. In databases, data are stored in a more structured way than files. In databases to save storage and improves access time, data duplication can be removed by normalizing the database. In terms of data 125

security, it is easier to apply access constraints in database systems so that only authorized users can access the data. By applying constraints, data privacy can be maintained. Searching, adding new data, updating existing data, and deleting old data in a database is very quick and easy. 6.3 CONTENTS OF A DATABASE: In the previous section, we have discussed that databases are very efficient in storing huge data. But how to store data in a database? To know how to store data in a database we should know the contents of a database. The primary content of a database is database table where all data of a database are stored. A table in a database is a structure to store a set of data with common attributes. Each attribute in a table is called fields and used as columns of the table. Data is stored in a table in terms of rows by putting values for every column. Each row in a table is called a record. Table 6.1 is an example of a database table of teachers in a school. There are three fields and four records in the table. Normally in a database table, the number of fields is fixed during the design of the database. Whereas insertion of new records occurs frequently. NAME ADDRESS MOBILE NO S Sarma Guwahati 9999999999 K Nath Jorhat 8888888888 B Das Guwahati 5555555555 S Sarma Mirza 6666666666 Table 6.1: A database table with different fields. 6.4 UNIQUENESS OF RECORD : Database tables are used to store a massive amount of information that is stored across multiple records. To retrieve a record precisely, the uniqueness of records is very important. Not only for retrieving, but the uniqueness of record is also important to perform an update and delete operation on a table. For example, in Table 6.1 there are two entries with the same value (S Sarma) for the NAME field. If we perform an update or delete operation in the table based on the name field, both records will be updated or deleted. For example, if we update the ADDRESS field to “Delhi” of “S Sarma” two records will be updated. That is, we cannot uniquely identify a record by the NAME field in this table. To maintain the uniqueness of records we define keys in a table. Keys are nothing but a field or a collection of fields whose value never repeats in a table. In Table 6.1 the “MOBILE NO” field can be used as a key since one mobile number does not belong to more than one person. We can also add one or more additional fields in a table as a key field. For example, we can redesign Table 6.1 as Table 6.2 by adding the “ID” field additionally. There are different types of keys in a database table. 126

ID NAME ADDRESS MOBILE NO 101 S Sarma Guwahati 9999999999 102 K Nath Jorhat 8888888888 103 B Das Guwahati 5555555555 104 S Sarma Mirza 6666666666 6.5 PRIMARY KEY: In a database table, we can designate one field or a combination of fields together as a primary key. The property of a primary key or primary key constrain is that no more than one record is allowed with the same value for that field. Besides this constrain, we also cannot add a record in a table without filling in the value of a primary key field. In Table 6.2 we cannot designate the NAME field as the primary key. Because there are multiple rows in the table with the same value in the NAME field. But we can designate the ID field as the primary key. 6.6 SUPER KEY: Super key is a set of fields in a database table that can uniquely identify a record in the table. But a super key may have some other fields which aren’t necessary for uniquely identifying a record in the table. In Table 6.2 we can see that the ID field can uniquely identify a record. To form a super key, we can combine any other field with the ID field. For example, <ID, NAME> together form a super key which also can identify a record uniquely. 6.7 CANDIDATE KEY: A field or a group of fields that can be used as a primary key of a table is called a candidate key. In Table 6.2 “ID” and “MOBILE NO” both are candidate keys. In a database table, if there are N candidate keys, anyone out of N can be used as the primary key. In that case, the remaining N-1 candidate keys are called alternate keys. In the previous table, if we designate the “ID” field as the primary key, the “MOBILE NO” field will be called an alternate key. If there is a candidate key which is composed of more than one field, then that candidate key is called a composite key. 6.8 RELATIONAL DATABASE: In Relational Database data are not stored in a single and very large table. There are many disadvantages of storing data in a single table. In a relational database, data are stored in multiple tables by making a relation among tables based on the primary key. Let us take an example. Suppose in a school, a database of books and authors is to be maintained. The following table can be used to store such information. 127

Author Book Dr. A. P. J. Abdul Kalam Wings of Fire: An Autobiography M. K. Gandhi The Story of my Experiments with Truth M. K. Gandhi Hind Swaraj Lisa Lutz Heads You Lose David Hayward Heads You Lose Dr. A. P. L. Abdul Kalam Inspiring Thoughts: Quotation Series Dr. A. P. K. Abdul Kalam Ignited Minds: Unleashing the Power within India Table 6.3: A table showing a list of books and authors. We can see that in this table some information is stored repeatedly. This happens because of the structure of the table and the nature of the data. In the “Author” field repetition happens because one author may have written multiple books. Similarly, in the “Book” field repetition happens because there may be one book written by multiple authors. Repetition of such information in a database is called redundancy. In a relational database, we should avoid redundancy to reduce error. If you notice, you can find that the spelling of “Dr. A. P. J. Abdul Kalam” is wrong in the last two entries of the table. To correct the spelling, we need to update two entries of the table. But, if we do not repeat the author name with each book and store it in a central store, a single update operation can rectify the error for every book. To do that three tables to be created as below. Using the third table we can map authors to books. Author_ID Author 1 Dr. A. P. J. Abdul Kalam 2 M. K. Gandhi 3 Lisa Lutz 4 David Hayward Table 6.4: A table to store author names. Book_ID Book 1 Wings of Fire: An Autobiography 2 The Story of my Experiments with Truth 3 Hind Swaraj 4 Ignited Minds: Unleashing the Power within India 5 Heads You Lose 6 Inspiring Thoughts: Quotation Series Table 6.5: A table to store books names. 128

Author_ID Book_ID 1 1 2 2 2 3 1 4 3 5 4 5 1 6 Table 6.6: A table to map Author_ID and Book_ID using foreign keys. 6.9 FOREIGN KEY: A foreign key is a key that is used to establish a link between two tables. It is nothing but a field (or collection of fields) in one table that refers to the primary key in another table. For example, in Table 6.6 “Author_ID” and “Book_ID”, both are foreign keys where “Author_ID” refers to Table 6.4 and “Book_ID” refers to Table 6.5. 6.10 WHAT IS MS ACCESS?: Microsoft Access is the most popular RDBMS that comes as a part of the Microsoft Office suite. It is a database management system (DBMS) that combines the relational Microsoft Jet Database Engine with a graphical user interface and software-development tools. MS Access can be used to develop application software and is generally used by data architects, software developers and power users. Following are the major uses of MS Access:  Manage accounts and bills  Store data in the form of tables and edit or customise them later as per the requirement of the user  It can be used to make our websites  Comparing data or finding a relationship between the existing data can be done using Access THERE ARE TWO TYPES OF DATABASE IN MS ACCESS: Flat File Database: When the data is stored in the form of a plain text file and cannot incorporate multiple tables. Relational Database: When the data is stored in a form that the data items are related to one another. It supports multiple tables which organise the text in rows and columns. 6.10.1 Objects/Components of MS Access: A Microsoft Access database is made up of several components, including tables, forms, queries, and reports. These components are called database objects. The major components or objects of MS Access database are discussed below: Tables: Table is an object that is used to define and store data. When you create a new table, Access asks you to define fields which is also known as column headings. 129

Queries: A query allows you to retrieve information from one or more tables based on a set of search conditions you define using the table fields. Forms: Forms are an Access tool that you can create to make data entry in database tables easier. You use forms to customize the presentation of data that your application extracts from queries or tables. Report: Once all the information is entered into the database, it can be reviewed or analysed using a report. A report is an effective way to analyze and present data using a specific layout. Other MS Access Objects: Macro : This object is a structured definition of one or more actions that you want Access to perform in response to a defined event. An Access Macro is a script for doing some job. Module : Module is an object in desktop databases containing custom procedures that you code using Visual Basic. Modules provide a more discrete flow of actions and allow you to trap errors. 6.10.2 Creating a blank database To create a database, we first need to open MS Access and you will see the following screen. In the left pane, the template categories—including the featured local templates—are listed, as well as the categories on Office Online. Templates are prebuilt databases focused on a specific task that you can download and use immediately. You will also see the New Blank Database option, which allows you to build your own database from scratch. Figure 6.10.1: Blank Database When you choose the New Blank Figure 6.10.2: Creating a Blank Database Database option at the top of the window, you will be prompted to rename the database from the default name, which is Database1.accdb. Rename the database whatever you want. In the example below, we named the database Student. 130

6.10.3 Different views of a table: You can work on a table in two views: Design View and Datasheet View. Design View In Design View of the table, you can enter the field names, their data types and description. Datasheet View Datasheet View, which looks like a spreadsheet, is used to enter data in a table. This view displays the table as a grid. The fields are displayed as columns and the records are displayed as rows. 6.10.4 Adding a Table When you create an Access database, you store your data in tables—subject-based lists that contain rows and columns. For instance, you can create a Contacts table to store a list of names, addresses, and telephone numbers, or a Products table to store information about products. This article explains how to create a table, add fields to a table, set a table’s primary key, and how to set field and table properties. The new database opens with one table showing as a default. It also defaults to naming this table Table1 in both the navigation pane and the Table tab itself. You will want to name your tables based on your database design plan. 6.10.5 Naming a table: To give the table a unique name, you must first click on the Microsoft Office button in the upper-left corner of the application. Next, select Save from the menu. The Save As dialog box will appear to let you save the table whatever name you want. The new table names appear in both the Figure 6.10.3: Default name of a database navigation pane and the Table tab itself. 6.10.6 Rules for Naming a Field: Following are some rules for naming a field: A field name can range from 1 to 64 characters. A field name can include letters, numbers and some special characters. Generally, the underscore (_) sign is used. A field name cannot start with a blank space. A field name cannot have a period (.), exclamation (!) or brackets () 131

6.10.7 Data Types THE FOLLOWING ARE THE AVAILABLE DATA TYPES IN ACCESS 2007 DATA TYPES DESCRIPTION Auto Number An AutoNumber field creates unique values automatically when Access creates a new record. The AutoNumber field is primarily used for Primary Keys in Access. Text A Text field can contain values that are text, numeric or a combination of both. A text field can contain a maximum length of 255 characters. Memo A much larger version of the text field, allowing storage of up to 2 GB of data. Number The Number field can store numeric values up to 16 bytes of data. Date/Time The Date/Time field allows storage of date and time information. Currency The Currency data type stores values in a monetary format. This can be used with financial data as 8-byte numbers with precision to four decimal places. Yes/No Boolean data storage of true/false values. OLE Object The OLE Object field stores images, documents, graphs etc. from Office and Windows based programs. Hyperlink The Hyperlink field type is used to store web addresses. This has a maximum size limit of 1 GB of data. Attachment The Attachment field type is used to store images, spreadsheet files, documents, charts and other types of supported files to the records in your database. 132

6.10.8 To Switching views: Select the Views command group from either the Home tab or the Datasheet tab on the Ribbon. Select the view option you want from the menu. Figure 6.10.4: Switching different views 6.10.9 Adding fields in Datasheet view By default, Access 2007 creates one field in each new table: the ID field. This field auto- numbers to give each record in the table a unique number identifier. Figure 6.10.5: ID field added automatically. To add more fields to a table in Datasheet view, double-click the Add New Field header. 6.10.10 Adding fields in Design view In Design view, the field names are along the left-hand column instead of across the top like in Datasheet view. To add a new field to a table in Design view, click in the cell where you want the new field and type the field name. 133

6.10.11 To add records in the new record row:  Click the record row with the asterisk that appears at the bottom of the table.  Type the data into the appropriate fields.  Hit Enter or the Tab key to move to the next field. 6.10.12 Editing records in tables: After entering data in a table, sometimes it is required to make changes in the database. Scroll through the records, or use the navigation buttons on the navigation bar to find the record to edit. Figure 6.10.7: Navigation Buttons  Click the cell containing the information that must be edited. A pencil icon appears to indicate edit mode.  Type the new information into the field.  Click outside of the record row to apply the change. 6.10.13 Moving fields: If you want to rearrange the order in which your fields appear in a table, Access 2007 lets you easily move them around. To move a field in Datasheet view, drag and drop the field to the location you want. To do this:  Click the field header for the field you want to move.  Move the mouse in the area of the header.  When the cross with arrows appears, hold down your left mouse button.  With the left mouse button still held down, move the cursor to where you want the field to appear.  Release the mouse button, and the field appears in its new location. 6.10.14 Deleting fields: To delete a field in Datasheet view, click the field header, then select Delete from the Field & Column command group. Using field properties to ensure data integrity  Field Size can be set to hold a specific number of characters, up to as many as 255 for text fields.  The Format field property can be set to display text or numbers in a standardized way.  Set the Required property to Yes if you want users entering data to be required to enter something in the field. Choose No if users are allowed to leave the field blank. 134

6.10.15 What is a Query?: In general, a query is a simple question that you ask to find some specific information from the database. In Access, when you build a query, you are defining specific conditions. In other words, Queries allow you to retrieve information from one or more tables based on a set of search conditions you define. Queries are made on tables and the results are displayed in the form of table, i.e., in a group of rows and columns with the set of records that match the given condition. Microsoft Access provides various types of queries; Select, Parameter, Crosstab, Action and SQL (Structured Query Language) query. 6.10.16 Setting a relationship between tables: Relationships are links that associate a field in one table with the same field in another table. In Access, you can store data in multiple tables. To bring that information together, you need to define relationships between the tables. Once you have defined relationships between the tables, data from both the tables can be used by Query, Form or Report. A relationship works by matching a field with the same name in both the tables. In most of the cases, these matching fields are the Primary key from one table that uniquely indentifies each record in a table and a Foreign key in the other table. 6.10.17 To establish a relationship between tables: Figure 6.10.8: Relationships Click the Relationships command in the Figure 6.10.9: Show Table Dialog Box Show/Hide group on the Database Tools tab in the Ribbon. WHEN THE SHOW TABLE DIALOG BOX APPEARS:  Select each table name, then click Add for the tables you want to relate.  When you’re done, close the Show Table dialog box. You should now see a relationship map that contains all of the tables that were selected. Drag the primary key of the parent table (e.g., Student Table) and drop it over the same field in the child table (e.g., Marks Table). In our example, Roll_no is the primary key. The Edit Relationship dialog box appears. Click on the Create button. Access creates the relationship between the tables. A line linking the two tables will appear indicating that both have been linked on the basis of linked field. 135

Figure 6.10.9: Show Table Dialog Box Click on the Save button on the Quick Access Toolbar to save the relationship and then close the Relationship window by clicking the Close button on the Relationship group. 6.10.18 Creating a Query in Design View:  Select the Query Design command from the Create tab on the Ribbon.  Use the Show Table dialog box to select which tables and/or queries to include in the query.  The selected table will appear as a small window in the upper section of the Query window i.e., the Object Relationship Pane.  The selected query table displays a list of fields. Double – click on the field names you would like to add in the query. They will be added to the Design Grid i.e., the bottom section of the Query window. You can also add fields to the query by dragging them from the field list to the Design Grid. Figure 6.10.12: Parts of Query Window 6.10.19 Understanding Design Grid: Field – The first row of the Design Grid displays the selected field names from the table. Table – This row displays the name of the existing table. Show – The show row displays a check mark. The fields with check marks displays during when the query is run. To hide the field during run time, deselect the check mark by clicking on it. Sort – This property is used to filter the data either in an ascending or descending order. Criteria – This property contains the condition on the basis of which the records will be filtered in the Query output. Or – This property is used to set multiple criteria in a query. 136

6.10.20 Saving a query:  Right-click the Query tab.  When the Save As dialog box opens, give your query a suitable name.  Click OK.  The query will now be listed in the object list on the left side of the Access window. 6.10.21 What are Forms? In real life, a form is piece of paper you fill out so someone can collect and keep track of specific information about you. Likewise, in Microsoft Access, Forms work quite similar to it. An Access form lets you enter data one record at a time, without having to see the entire table. Microsoft Access form also lets you know exactly what information to enter and can even tell you what that information should look like. Adding certain control components to a form—like a drop- down menu—can dramatically increase the integrity of the data that is held in a database. A Form can have a different name from a table, yet it manipulates the same information and data to the corresponding table. If you change a record in a form, it will be reflected in a table also. Data can be inserted, updated and deleted from a table by using the Form object. 6.10.22 Creating a form: Access 2007 has several automatic tools for creating forms. These tools are located in the Forms group on the Create tab in the Ribbon, as seen below: Figure 6.10.13: Creation of Form Access 2007 forms tools include:  The Form command makes a basic form, showing a single record at a time.  The Split Form command creates a form showing one record on top and includes the Datasheet view of the entire source table on the bottom.  The Multiple Items command creates a form that shows all records at once, which looks similar to the source table in Datasheet view.  The Form Wizard is hidden under the More Forms command. It walks you through the process of creating more customized forms. 6.10.23 To create a form using the Form command: The basic Form command is the one we suggest because it allows you to see just one record at a time. It also includes all of the fields in your source table for you, and you can modify the layout of the basic form to hide fields or add controls: 137

 Begin by highlighting the table you want to use as a source table.  With the source table highlighted, select the Form Command from the Forms command group in the Create tab on the Ribbon.  The new form is created and opens in the object pane. 6.10.24 To add a record using a form: Figure 6.10.14: Adding record using form  Navigate to a new record, either by using the New Record navigation button or by using the New command in the Records group on the Ribbon.  Add the new data.  Save the record. 6.10.25 What are reports?: A report is an effective way to present your data using an attractive layout. The text can be formatted in an Access report similar to how it can be done in Word documents. A report can be created exactly in the same way as we have created the form. The only change is that after selecting the Create tab, click on the Reports in the Reports group. Access creates a report and places all fields of the selected table in the report. Following are the four different types of views in which a report can be displayed. REPORT VIEW– You can view data of the report in this view but cannot make modification in the design. PRINT PREVIEW– This view allows you to see how the report will look when printed. Figure 6.10.15: Different views of report LAYOUT VIEW– It provides a view that closely resembles what the report will actually look like to the user. DESIGN VIEW– This view displays only the structure of the report which can be modified and customised as per requirement. 6.10.26 Printing a report:  To print a report, select the Print Preview View option.  This view displays how the report will appear on a page. It also allows you to choose Page orientation, Page setup etc.  If needed, modify the page size, margin width and page orientation.  Click on the Print option. The Print dialog box appears. Set the desired print option and then click OK. 138

Keywords learned in this chapter: Database DBMS Table Field Record Key Relational Database Redundancy Query Form Report EXERCISE 1. MCQ B) Set of computer programs. C) Key D) Field 1. DBMS is a A) Type of database. 2. Which of the following key composed of additional fields? A) Primary B) Foreign C) Super D) Alternate 3. Which option is used to change the appearance and size of various controls of a Form? A) Design View B) Form View C) Layout View D) None of these 4) Which key defines a relationship between two tables? A) Primary key B) Candidate key C) Secondary key D) None of these 5) Which icon indicates the edit mode in Access? A) Clip B) Pen C) Pencil D) None of these 2. Fill in the blanks: 1. In __________ database data are stored in multiple tables to remove redundancy. 2. A candidate key is called ___________ key, if it is not designated as primary key. 3. Microsoft Access is a _________________ database. 4. ___________ view displays the table as grid. 5. _________ allows you to add and update data in a table, one record at a time. 3. Answer the following questions: 1. What is Database? Give examples 2. What is the need for database? 3. Define: Primary key, Foreign key, Candidate key, Super key. 4. Differentiate between Flat file database and Relational database. 5. What are data types? List the various types of data types used in Access 2007 and explain any four of them. 6. What is a query? Explain the parts of a query window. 7. What do you understand by criteria? 139

CODING AND ITS 7CHAPTER IMPORTANCE “Whether you want to uncover the secrets of the universe, or you just want to pursue a career in the 21st century, basic computer programming is an essential skill to learn.” - Stephen Hawking In this chapter, we will step into the world of coding. We will see the importance of coding or programming. We will learn about the languages of computers. Thereafter, we will also learn about problem solving in computers with the help of programming. 7.1 AN INTRODUCTION TO CODING Have you heard the term “coding”? The term coding has received an enormous amount of attention in recent times. We often hear the term in several places including advertisements on television and others. Here we will learn about coding and its importance in today’s world. Before understanding coding, let us first have a discussion on “What does a computer understand?” and “How do we communicate with a computer?”. We have seen in Chapter 1 that a computer runs on electricity and operates on discrete voltage levels: 0 and 1. We have also learned that every computer has a processing element, known as CPU. Every CPU understands only a set of instructions or commands. These commands along with some other internal details of a CPU is known as instruction set architecture (ISA). After under- standing a command, CPU performs the work specified in the command with the help of its internal circuitry. Understanding a command by the CPU is also known as decoding an instruction. If we want to communicate with our computer or if we want our computer to do a work, we must give the command that is understandable by the CPU of the computer. These commands are actually some sequence of binary numbers, expressed in hexadecimal format. Coding means writing these commands to instruct our computer to do some meaningful work. The work can be simply to display our names on monitor, adding two numbers or to move a robot in a direction, etc. Coding is also popularly known as programming. We will use both the terms (coding and programming) interchangeably in this book. Till now, we have been using computers to do different kinds of work on it. For example, playing a game, making a powerpoint presentation, drawing pictures, etc. In those cases, we simply use the applications developed by others and we are the users of it. In this chapter, we will have a look from the other direction. 140