New Gateway to Computer Science 8

150 New Gateway to Computer Science Book-8 To insert a blank table Place the mouse over the diagram squares to select the number of columns and rows in the table. Click and drag the mouse. The table will appear on the slide. You can now place the insertion point anywhere in the table to add text. To move a table: Place the cursor over the edge of the table. The cursor will turn into a cross with arrows . Click and drag the table to the desired location. Release the mouse button to drop the table in the new location. You can now place the insertion point anywhere in the table to add text. Modifying tables To resize a table: Place the mouse over one of the sizing handles located around the edge of the table. The cursor will become a pair of directional arrows . Click, hold, and drag your mouse to make the table larger or smaller. Release the mouse. The table will be resized. To add a column or row: Place the insertion point in a cell adjacent to the location where you want to add a row or column. Scan Here For video tutorials

151 New Gateway to Computer Science Book-8 Select the Table Tools Layout tab, and locate the Rows & Columns group. If you want to insert a new row, select either Insert Above or Insert Below. If you want to insert a new column, select either Insert Left or Insert Right. A new row or column will appear. To delete a row or column: Select the row or column by placing the insertion point in any cell in that row or column. Select the Table Tools Layout tab. In the Rows & Columns group, click Delete. A drop-down menu appears. Select Delete Rows or Delete Columns. Modifying the table style To apply a table style: Click anywhere on the table. The Table Tools tab will appear on the Ribbon.

152 New Gateway to Computer Science Book-8 Select the Table Tools Design tab, and locate the Table Styles. Click the More drop-down arrow to see all of the table styles. Place the mouse over various styles to see a preview. Select the desired style. Inserting Audio You can add sound to your presentation. You can add background music to one slide, a sound effect to another and one narration or commentary to a few slides. You can either add an audio file from your computer or browse PowerPoint’s collection of clip art audio. You can edit the sounds as required.

153 New Gateway to Computer Science Book-8 To insert audio from a file on your computer: Click on Insert tab, click the Audio drop-down arrow from media group and select Audio from File. Locate and select the desired audio file, then click Insert. The audio file will be added to the slide. To insert clip art audio: From the Insert tab, click the Audio drop-down arrow from the media group. and select Clip Art Audio. The Clip Art pane will appear on the right. Scan Here For video tutorials

154 New Gateway to Computer Science Book-8 Enter keywords in the Search for: field, then click Go. The results will appear in the Clip Art pane. To preview an audio file, rightclick the file and select Preview/Properties. A dialogue box will appear, and the audio file will start playing automatically (it may take a few seconds to load). To play it again, press the Play button.

155 New Gateway to Computer Science Book-8 When you finished previewing the file, click on Close. Once you have found the audio file you want to use, click it to insert it into the slide. Recording your own audio You can record the audio and directly place into a presentation. For that you must have a microphone that must be compatible with your computer system. Many computers have built-in microphones or ones that can be plugged in to the computer. To record audio: From the Insert tab, click on the Audio drop-down arrow from media group and select Record Audio. Type a name for the audio recording.

156 New Gateway to Computer Science Book-8 Click the red Record button to start recording. When you are finished recording, click on the Stop button. To preview your recording, click on the Play button. When you’re done, click on OK. The audio file will be inserted into the slide. To trim the audio: You can trim some part of your audio. To do this you can use the following step. From the Playback tab, click the Trim Audio command. The Trim Audio dialogue box will appear.

157 New Gateway to Computer Science Book-8 Use the green and red handles to set the start time and end time. To preview the audio file, click the Play button. Adjust the green and red handles again if necessary, then click OK. To add a fade in and fade out: On the Playback tab, locate the Fade In and Fade Out fields. Type in the desired values, or use the up and down arrows to adjust the times. Audio options There are other options that you can set to control how your audio file plays. These are found in the Audio Options group on the Playback tab.

158 New Gateway to Computer Science Book-8 Volume: This changes the audio volume. Start: This controls whether the audio file starts automatically or when the mouse is clicked. Hide During Show: This hides the audio icon while the slide show is being played. Loop Until Stopped: This causes the audio file to repeat until it is stopped. Rewind After Playing: This causes the audio file to return to the beginning when finished playing. A chart is a tool that you can use to communicate your data graphically. The data series consists of the related data points in a chart. The legend identifies which data series each colour on the chart represents. You can also add sounds in a slide. To insert Clip Art audio, you can go to insert tab. You can record the audio and directly place into a presentation. Quick Learn Open an existing PowerPoint presentation. Select a slide and apply a transition. Change the transition duration. Add a sound effect to the transition. Apply this transition and its settings to all slides. Apply a different transition to one slide. Remove the transition. Lab Activity 1

159 New Gateway to Computer Science Book-8 Open an existing PowerPoint presentation. Insert a new chart. Change the chart layout. Apply a chart style. Lab Activity 2 Open an existing PowerPoint presentation. Insert an audio file from your computer. Preview the audio file. Trim the audio file. Add a fade in and fade out. Add a clip art audio file. Change the picture for one of the audio files. If your computer has a microphone, record some audio into a slide. Experiment with the different audio options on the Playback tab. Lab Activity 3 1. Fill in the blanks with suitable words. a. PowerPoint is a ………………..program. b. The presentation is made up of a series of ………. c. To check spelling you can go on ……………tab. d. Red wavy lines indicates the …………….errors. e. A theme is a ……………….combination of colours, fonts and effect that can be applied to the presentation. f. To change the theme colour you can use ………….tab. g. You can change the ……………..colour and texture by choosing a different background style. EXERCISE

160 New Gateway to Computer Science Book-8 h. The …………consists of the related data points in a chart. i. A table is a ……….of cells arranged in rows and columns. j. You can …….the audio and directly place into a presentation. 2. State whether the following statements are true or false. a. PowerPoint is a spread sheet program. b. PowerPoint presentations work like slide shows. c. You can modify themes by combining the colour, fonts and effects from different themes and you can customize them. d. You can change the background colour and texture by choosing a different background style. e. A table is a tool that you can use to communicate your data graphically as a picture. f. The vertical axis is known as legend. g. The horizontal axis is also known as the x axis. h. You cannot place the audio in the slide. i. To record an audio you can click on home tab. 3. Write down the proper steps for the followings. a. To change theme effects. b. To insert a chart. c. To change the chart layout. d. To insert a blank table. e. To add column or rows. f. To record your own sound. 4. Write very short answer to the following questions. a. Can we work with spelling and grammar checking options in power point? If yes, which tab can be used? b. What is the use of ‘ignore once’ in spelling check dialogue box? c. Which function key is used to view presentation? d. Which tab can be used to insert chart in presentation? e. What is the use of CTRL + C and CTRL + V shortcut key? f. What are the other three options available with Audio drop down list?

161 New Gateway to Computer Science Book-8 5. Write short answer to the following questions. a. What is PowerPoint? For what purpose can you use PowerPoint? b. Write down the common features of PowerPoint. c. What indicates grammar and spelling errors in PowerPoint? d. Define theme. Write down the steps to create a new theme colour. e. Write down the steps to change the background style. f. Define chart and name some types of charts. g. Write down the Name of the parts of a chart. h. Can you insert an audio in a presentation? If so, write the steps to add it in a slide. 6. Write long answer to the following questions. a. What is theme? Explain the ways to change the theme colour, theme fonts and theme effects. b. What is the purpose of inserting an audio in a slide? Write down the step to insert clipart audio and recording own audio. c. Explain the types of chart with its various parts. Design some slides to explain about your school by using the following slides: Title slide Bulleted list slide Column slide Slide with inserting table Slide with inserting chart Slide with organization chart Apply some design template on above slide. Create a pie chart on power point (you can make a list of male and female teachers of your school in a chart.) Make a slide and record your voice and place on your slide. Lab Activities

ICT, Computer Ethics and Cyber Law Unit 2 Chapter 10 Chapter 11 Chapter 12 Chapter 13 Chapter 14 Web Page Designing with HTML Information and Communication Technology Computer Ethics and Cyber Law Computer Virus Introduction to Computer Networking Inside the Unit

163 New Gateway to Computer Science Book-8 Introduction Internet is the basic tool for human in this 21st century. Human life is almost incomplete without the internet these days. It is used for various purposes like for education, health, sports, entertainment and so many other fields. All types of information on the internet are stored on web server which can be viewed with the help of web site. The website is the collection of web pages which can be created by using some web page designing applications. We can say web design is the process of creating websites. It includes different aspects, including web page layout, content production, and graphic design. Basic terminology Web page A web page is a document commonly written in Hyper Text Mark-up Language (HTML) that is accessible through the Internet or other network using an Internet browser. A web page is accessed by entering a URL address. With the collection of web pages we can develop the web site. Web Page Designing with HTML 10 Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • define the various terminologies • list out the features of HTML and explain the HTML Tags. • identify the structure of HTML document and Prepare HTML document. • work with paragraph alignment and work with HEADING TAG. • change the font colour size and face. • work with various HTML tags.

164 New Gateway to Computer Science Book-8 HTML Hyper Text Mark Up language was developed by Tim Berners Lee in 1990 AD. HTML is the standard mark-up language for creating web pages and web applications. Hypertext is the method by which you can move around the web page by clicking on special text called hyperlinks. Web browser A web browser is application software used to access and view websites. We can also define web browser as a software program that allows a user to locate, access, and display web pages. Web browser is also called “browser.” Browsers are used mainly for displaying and accessing websites on the Internet, as well as other content created using Hypertext Mark-up Language (HTML) and Extensible Mark-up Language (XML). Opera, Google Chrome, Mozilla Firefox, Internet Explorer, Safari, etc. are the popular web browsers. Search Engine Search engines are used to view the web documents based on keyboards. It is a web-based tool that enables users to locate information on the World Wide Web. Popular examples of search engines are Google, Yahoo!, ask.com, etc. A dictionary meaning of search engine is “a computer program that searches documents, especially on the World Wide Web, for a specified word or words and provides a list of documents in which they are found.” Hyperlink Simply hyperlink means linking with multiple pages. Hyperlink is a word, phrase, or image that you can click to jump in a new document or a new section within the current document. Hyperlinks are found in all Web pages. A hyperlink is an element in an HTML document that links to either another portion of the document or to another document. Working with HTML In this class, we are going to discuss the HTML. We are going to learn some basic tags used by HTML. Features of HTML It helps to create a web page with the help of various tags.

165 New Gateway to Computer Science Book-8 It helps to create a link between or among the documents. It helps to create data in a tabular format. It helps to insert pictures and symbols. It helps to create a form. Internet is used for various purposes like for education, health, sports, entertainment and so many other fields. All types of information on the internet are stored on web server. The website is the collection of web pages which can be created by using some web page designing applications. A web page is a document commonly written in Hyper Text Mark-up Language (HTML) that is accessible through the Internet or other network using an Internet browser. Hyper Text Mark Up language was developed by Tim Berners Lee in 1990 AD. A web browser is application software used to access and view websites. Search engines are used to view the web documents based on keywords. Hyperlink means linking with multiple pages. A hyperlink is an element in an HTML document that links to either another portion of the document or to another document. Quick Learn HTML Tags HTML tags are the hidden keywords within a web page that define how your web browser displays the content. Most tags must have two parts, an opening and a closing part. For example, <html> is the opening tag and </html>is the closing tag. The closing tag has the same text as the opening tag, but has an additional forward-slash ( / ) character. <HTML>, <HEAD>, <BODY>, <B> etc. are the examples of HTML tag. There are two types of HTML tags. Container Tag : This tag has both starting and the ending tag which are enclosed with the help of angular bracket (<>). In container tag, we must use slash (/) to close the tag as</ B>. For example <U> tag start the underline and </U> close the underline. Empty Tag: This tag does not have the ending tag but it has starting tag. For example <BR> code does not have ending tag.

166 New Gateway to Computer Science Book-8 Structure of HTML document <html> <head> <title> Tile of the web page </title> </head> <body> Content of the document that you want to display… </body> </html> <html></html> : This basically defines the document as web page. It also identifies the beginning and end of the HTML document. All other tags must fall between the html tags. <head></head>: The header contains information about the document that does not appear on the actual page, such as the title of the document, the author. <title></title>: The title tag defines the title that will appear in the title bar of your web browser. The title must appear between the head tags. <body></body>: The body tags contain all the information and other visible content on the page. All your images, links and plain texts must go between the <body> and </body> tags. Preparing HTML document With the help of HTML tag, we can create HTML documents. To write HTML tag we can use the text editor program like Notepad. We can save the notepad file with .html extension and view it with the help of web browsers. Starting Notepad Press windows key and R at the same time (Windows key + R) from the keyboard. A Run dialogue box will appear. Type Notepad in the box and press enter Now you can view the notepad screen as below.

167 New Gateway to Computer Science Book-8 Use various HTML tags as required. Save this file with .htm or .html extension in your required location of storage. After it, use any web browser to view the page as a web page. Text formatting tags in HTML <B> text </B>: This tag is used to make the text bold and close it. <I> text </I>: This tag is used to make the text italic and close it. <U> text </U>: This tag is used to insert the underline in the required text and close it. <SUP> text < SUP>: This tag is used to convert the text in superscript format. <SUB> text <.SUB>: This tag is used to convert the text in subscript format. <P>: This tag is empty tag used to change the paragraph. <BR>: This tag is used to break the line. <HTML><HEAD> <Title> This is the first sample. </title </HEAD> <BODY><B> code is used to make the text bold.</B><BR> <I> code is used to make the text italic. </I><BR> <U> code is used to insert underline in the text.</U><BR> We can use formula in HTML as given <BR> A² + 2ab + b² as to display in superscript and H<sub>2</ sub>SO₄ as subscript. </BODY></HTML> Lab Activity

168 New Gateway to Computer Science Book-8 Output Changing the paragraph alignment <P> Tag This option is used to move the text or paragraph or an image to the centre, left or right part of the screen. We can also justify the text with paragraph alignment tag. Syntax: <P align = “Center” | “Left” | “Right” | “Justify”>text </P> Open NOTEPAD and type the below text and display the result. <HTML><HEAD> <Title> this is second sample. </title </HEAD><BODY> <P align = “Center”> This is our second sample <P><br> <P align = “left”> This is our second sample <P><br> <P align = “right”> This is our second sample <P><br> <P align = “justify”> This is our second sample on HTML. <br> We can use HTML for writing the tags. <br>We can apply formula and others in HTML. <br> We can also work with table and so on. <P><br> </body> </html> Lab Activity

169 New Gateway to Computer Science Book-8 Output Heading tag <Hn> Tag You can use different sizes for your headings. HTML has six levels of headings, which use the elements such as<H1>, <H2>, <H3>, <H4>, <H5>, <H6>. While displaying any heading, browser adds one line before and one line after that heading. Syntax: <H1> …………….</H1> <H2> …………….</H2> <H3> …………….</H3> <H4> …………….</H4> <H5> …………….</H5> <H6> …………….</H6> Where H1 is the largest heading and H6 is the smallest heading. <HTML><HEAD> <Title> this is heading sample. </title </HEAD> <BODY> <H1> This is heading 1.</H1><br> <H2> This is heading 2. </H2><br> <H3> This is heading 3. </31><br> <H4> This is heading 4. </H4><br> <H5> This is heading 5. </H5><br> <H6> This is heading 6. </H6><br> </body></html> Lab Activity

170 New Gateway to Computer Science Book-8 Output Font colour size and face <Font> Tag There are three different ways of defining a colour. The easiest way is to name the colour in English. For example: black, white, red, green and blue. We can also use colour code as below in HTML. Colour Hexa Colour Hex Colour Hex Colour Hex aqua #00FFFF green #008000 navy #000080 silver #C0C0C0 black #000000 gray #808080 olive #808000 teal #008080 blue #0000FF lime #00FF00 purple #800080 white #FFFFFF fuchsia #FF00FF maroon #800000 red #FF0000 yellow #FFFF00 Syntax: <FONT SIZE= “SIZE VALUE” COLOR = “COLOUR NAME” FACE= “FONT NAME” Text..........</FONT> Here, size is used for setting the absolute values ranging from 1 to 7. Colour is used for changing the font colour and face is used for changing the font name. <HTML> <HEAD> <Title> this is font colour size and face sample. </title </HEAD> <BODY> <FONT COLOR = #008000 size = “7” face = “Arial Black”>we all are Nepali and we are proud to be Nepali. </FONT> </body> </html> Lab Activity

171 New Gateway to Computer Science Book-8 In the given tag #008000 is the colour value for green, 7 is the size of the font and Arial Black is the name of the font which is also called font face. You can change the font colour, size and face as your requirement. Output Marquee Element <Marquee> Tag This element is used to make the text or picture movable. You can move the text or picture centre part, left part, right part, upwards, down wards, scroll and alternate. on the screen. Syntax: <MARQUEE BEHAVIOR= “SCROLL”/ “SLIDE” / “ALTERNATE”DIRECTION = “LEFT”/ “RIGHT” / “UP” / “DOWN” BGCOLOR = “COLOUR NAME OR VALUE” >Text……………</MARQUEE> Where, behavior enables you to set the movement of the marquee, direction specifies the direction in which the text will scroll, bgcolor set the background colour for the marquee with a colour name or value. <HTML><HEAD> <Title> this is marquee sample. </title </HEAD> <BODY> <FONT COLOR = #008000 size = “7” face =”Arial Black”> <marquee bgcolor = “red” behavior = “alternate”> We are learning the HTML. </ Marquee> </body></html> Lab Activity

172 New Gateway to Computer Science Book-8 Working with image <IMG> Tag We can insert various types of pictures in HTML document. Before inserting the picture you have to identify the extension of picture as it is .JPG, .GIF, .JPEG, .TIF or .BMPpicture. Syntax: <IMG SRC = “IMAGE NAME WITH LOCATION” ALIGN = “TOP” / “MIDDLE” / “BUTTON” / “LEFT” / ”RIGHT” / “CENTER” WIDTH = “IMAGE PIXEL” HEIGHT =”IMAGE PIXEL”> Where, src used to specify the source of image, align aligns text around an image in word wrap style, width specifies the width of the image in pixel and height specified the height of the image in pixels. <HTML><HEAD> <Title> this is image inserting sample. </title </HEAD> <BODY> <P align = “center”><IMG SRC = “child.jpg” width =”300” height =”500” </body></html> Lab Activity Output Hyperlinks and Anchors <A> Tag Hyperlink is essential in each web document. When you click on this link, you can view or open the new page. Syntax: <A HREF = “NAME OF THE WEB SITE”> Text ….. </A>

173 New Gateway to Computer Science Book-8 <HTML><HEAD> <Title> this is hyperlink sample. </title></HEAD> <BODY> <A HREF = “http://shubharambhapublication.com”> Visit our web page </A> </body></html> Lab Activity HTML tags are the hidden keywords within a web page that define how your web browser displays the content. There are two types of HTML tags, they are Container Tag and Empty Tag. Text formatting tags are used to format the text. Marquee element is used to make the text or picture movable. You can move the text or picture centre part, left part, right part, up wards, down wards, scroll and alternate, etc. on the screen. We can insert various types of pictures in HTML document. JPG, .GIF, .JPEG, .TIF or .BMP, etc. are the extension of pictures. Hyperlink is essential in each web document. When you click on this link, you can view or open the new page. Quick Learn 1. Choose the best answer from the given alternatives. a. Who was the creator of the first web page? i. Babbage ii. Tim Berners Lee iii. Lady Ada b. What is the extension of HTML file? i. .HTML ii. .DOC iii. .JPEG c. Which of the following is a web browser? i. Opera ii. Google iii. Facebook d. Which of the following is a search engine? i. Opera ii. Google iii. Facebook EXERCISE

174 New Gateway to Computer Science Book-8 e. What is the meaning of hyperlink? i. No any link ii. Link with in single page iii. Link with multiple pages f. What is the name of the starting page of any web pages? i. File page ii. Home page iii. Insert page g. Which of the following tag is used to place the text to the center align? i. <P Align = “Center”> ii. <P Align = “Right”> i ii. <P Align = “Left”> 2. Fill in the blanks with suitable words. a. The web site is the collection of ………………. which can be created by using some web page designing applications. b. Hyper Text Mark Up language was developed by ……………in 1990 AD. c. ………… are used to view the web documents based on keyboards. d. A ……… is an element in an HTML document that links to either another portion of the document or to another document. e. There are two types of HTML tags they are Container Tag and …………… f. ……………. element is used to make the text or picture movable. 3. State whether the following statements are true or false. a. All types of information on the internet are stored on web server. b. A web page is a document commonly written in Hyper Text Mark-up Language (HTML) that is accessible through the Internet or other network using an Internet browser. c. A search engine is an application software used to access and view websites. d. Hyperlink means linking with only single page. e. Text formatting tags are used to format the pictures. f. Hyperlink is essential in each web document. When you click on this link, you can view or open the new page. 4. Match the following. Google Tag to insert picture Firefox Adding horizontal line <HR> Search Engine <IMG SRC> Web Browser

175 New Gateway to Computer Science Book-8 5. Write down the function of the following HTML tags. <MARQUEE>, <IMG SRC>, <FONT COLOR>, <B>, <HR>, <TABLE>, <H1> 6. Write very short answer to the following questions. a. Name any two web browsers. b. Name any two popular search engines that you know. c. When was the first web page created? d. What are the types of HTML tag? e. Which tag is used to make the text italic and close it? f. Which colour code is use for green colour in RGB colour format? g. Can we use space at the beginning or middle of the tag? 7. Write short answer to the following questions. a. Define web browser and search engine. b. What is HTML? Write down the features of HTML. c. What is HTML tag? Explain its types. d. Define hyperlink with its examples. e. What is the default background colour of the web page? f. Which tag is used to make the text movable? 8. Write long answer to the following question. a. What do you mean by text formatting in HTML? Explain some text formatting tag with its syntax. Project Work & Activity • Prepare a web page using HTML tag where you can describe about your family and school. • Prepare a web site by describing about your locality. • Conduct a speech competition on the topic “Social media and its impacts”.

176 New Gateway to Computer Science Book-8 Introduction The Information and Communication Technology is making dynamic changes in the society in this 21st century. ICT has a great impact in our daily lives. ICT not only covers about the computer but also all the technological devices that people are using all over the world. Information and Communication Technology (ICT) refers to all the technology used to handle telecommunications, media, management systems, audiovisual processing, and network-based control and monitoring functions. ICT has become an integral part of everyday life for many people. It increases its importance in people’s lives, and it is expected that this trend will continue, to the extent that ICT literacy will become a functional requirement for people’s work, social, and personal lives. Information and Communication Technology (ICT) has an important role in the world since we are now in the information era. With ICT, the company can make the business easier to happen with the client, supplier and the distributor. It is also very important in our daily lives. The lack of appropriate information at the right time will result in low productivity, low quality research works, and waste of time to pursue information and even to do research which actually others had done in other countries. ICT is one of the economic development pillars to gain national competitive advantage. It can improve the quality of human life. It also provides wider knowledge and can help in gaining and access the information. Information and Communication 11 Technology Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students willbe able to: • tell about the ICT with its advantages and disadvantages. • write the application areas of ICT.

177 New Gateway to Computer Science Book-8 Advantages and disadvantages of ICT Advantages: It is massively used in the educational sector. It has great impact in the field of communication. It is used to promote e-commerce. It is used in distance learning and online health service. Disadvantages: It has increased the piracy of data and information. More chances of spreading viruses. Increasing the viewers of pornography. A great threat from the hackers. People are depending on other resources which may decrease the efficiency. The Information and Communication Technology is making dynamic changes in the society in this 21st century. ICT not only covers about the computer but also all the technological devices that people are using all over the world. ICT has become an integral part of everyday life for many people. Information and Communication Technology (ICT) has an important role in the world since we are now in the information era. Quick Learn Information technology is the technology used to store, manipulate, distribute or create information. It is a set of tools that can help to provide the right people with the right information at the right time Exploring Knowledge!

178 New Gateway to Computer Science Book-8 Application of ICT The major application areas of ICT are explained below. ICT in education The use of ICT in education is rapidly increasing day by day. The various ICT tools are used in school and colleges for the effective learning activities. A teacher can use ICT tools for teaching activities like laptop, projector, smart board, educational software, tablet, mobile and others. During teaching learning activities students can listen and watch various audio and video clips with the help of the internet. Nowadays, distance learning, online education, online exams etc. are possible due to the use of ICT tools. A student should not depend upon a teacher these days, they can use different web site and browse the related information at anytime from anywhere. ICT in Health ICT tools are being used at hospital for CT-Scan, ultrasound, endoscope, ECG, X-Ray to do the investigation of the patients. ICT tools are also used to keep the records of doctors, hospital staff, patients, doctor’s duty schedule, etc. Telemedicine and online medical advisees are also possible with the help of ICT tools. Telemedicine can be defined as the use of electronic communication technology to exchange patient information and provision of health care services at remote locations. To sum up, ICT in health sectors are used for the followings. Health and Education Hospital Management System Health Research Electronic Medical Record ICT in Banking Information and Communication Technology plays an important role in the development of banking industry. In fact, ICT has made the banking sector more competitive

179 New Gateway to Computer Science Book-8 because of advancement of information and communication technologies. ICT allows the banks to effectively cater the needs of the consumers by strengthening internal control systems which are backed by the effective communication mechanisms. The wide spread use of smart cards, ATMs, mobile banking, electronic banking, telephone banking, twenty four hours service, the overall quality of services, expanded portfolio of products and services, better customer relationship management with the use of advanced tools and variety of products has enabled banks to better serve their customers with the advent of ICT. ICT in Communication The world is very small due to the use of ICT in communication. You can connect with the people of the world with in a very few seconds. ICT tools are decreasing the distance between or among the people of the world. You can collect and transfer the information all over the world with in a few minutes. Nowadays, the use of e-mail, voice mail, web chat, uses of social media like Facebook, twitter, Viber are rapidly increased to have a communication effectively which are also the tools of ICT. Social media are interactive computer-mediated technologies that facilitate the creation and sharing of information, ideas, interests and other forms of expression through virtual communities and networks Exploring Knowledge! ICT in E-Commerce E-Commerce stands for electronic commerce which is used to buying and selling the goods over the internet. We can do online shopping and also promote the business. E-commerce refers to the purchase and sale of goods and/or services through electronic channels such as the Internet. E-commerce was first introduced in the 1960s via an Electronic Data Interchange (EDI) on value-added networks (VANs). E-commerce is subdivided into three categories: business to business or B2B like Cisco, business to consumer or \B2C like Amazon, and consumer to consumer or C2C like eBay.

180 New Gateway to Computer Science Book-8 A teacher can use ICT tools for teaching activities like laptop, projector, smart board, educational software, tablet, mobile and others. ICT tools are popularly used at hospital for CT-Scan, ultrasound, endoscope, ECG, X-Ray to do the investigation of the patients. Telemedicine and online medical advice is also possible with the help of ICT tools. ICT allows banks to effectively provide all services accurately. The world is very small due to the use of ICT in communication. You can connect with the people of the world with in a very few seconds. ICT tools are decreasing the distance between or among the people of the world. E-Commerce stands for electronic commerce which is used to buying and selling the goods over the internet. Quick Learn 1. Fill in the blanks with suitable words. a. The ……………………. are making dynamic changes in the society in this 21st century. b. ICT has become an ………………….. of everyday life for many people. c. A ………………… can use ICT tools for teaching activities like laptop, projector, smart board, educational software, tablet, mobile and others. d. ICT allows the ………………. to effectively provide all the services of bank. e. ICT tools are …………………. the distance between or among the people of the world. 2. State whether the following statements are true or false. a. ICT not only covers about the computer but also all the technological devices that people are using all over the world. b. Information and Communication Technology (ICT) has an important role in the world since we are now in the information era. EXERCISE

181 New Gateway to Computer Science Book-8 c. ICT tools are popularly used at bank for CT-Scan, ultrasound, endoscope, ECG, X-Ray to do the investigation of the patients. d. Telemedicine and online medical advice are also possible with the help of ICT tools. e. The world is very small due to the use of ICT in communication. f. You can connect with the people of the world with in a very few seconds. g. E-Mail stands for electronic commerce which is used to buying and selling the goods over the internet. 3. Write very short answer to the following questions. a. What is the full form of ICT? b. Are laptop and desktop computers related to technology? c. Is it possible to use ICT tools in education? d. Name any three ICT tools that can be used at your school. 4. Write short answer to the following questions. a. Define ICT with its advantages and disadvantages. b. What is the role of ICT in education? Describe in short. c. What types of services can we get with the help of ICT tools at hospital? d. What is the role of the ICT tools in communication these days? e. What is E-Commerce? What are the different categories of E-Commerce? Project Work & Activity • Conduct a speech competition on the topic “Role of ICT tools for education and communication in 21st Century. • Collect various ICT tools from different newspaper and paste in your chart paper. • Take an interview with your school principal about the various ICT tools that are being used and record an audio then present it in your classroom.

182 New Gateway to Computer Science Book-8 Introduction The history of computer ethics was started from 1950 AD. It is a branch of applied science. Computer ethics deals with how the computer experts should make decision regarding the social and professional behaviour while working with the computer tools and technology. It also deals with the procedures, values and practices that govern the process of consuming computing technology and its related disciplines without damaging or violating the moral values of any individual, organization or entity. Every society has its rules about whether certain acts are ethical or not. These rules have been established as a result of consensus in society and are often written into laws. Computer Ethics and Cyber Law 12 Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • define computer ethics and its provisions. • tell about the cyber crime. • write about cyber law and its area. • explain the cyber law of Nepal.

183 New Gateway to Computer Science Book-8 Computer ethics address the following things. Accountability Responsibility Liability Intellectual Property Right Obligation Quality of system and quality of life There are ten provisions of computer ethics defined by the Computer Ethics Institute. a. Do not use a computer to harm other people. b. Do not interfere with other people’s computer work. c. Do not snoop around in other people’s files. d. Do not use a computer to steal. e. Do not use a computer to bear false witness. f. Do not use or copy software for which you have not paid. g. Do not use other people’s computer resources without authorization. h. Do not appropriate other people’s intellectual output. i. Do think about the social consequences of the program you write. j. Do use a computer in ways that show consideration and respect Cyber crime Cybercrime is a criminal activity committed with the help of computer and computing tools. Cyber terrorists use computer tools to steal the personal information, spread viruses, hacking the website and blogs to earn the money. The growth of the internet is increasing in the volume of cybercrime activities. These days people are also using social media like facebook and others to commit criminal activities so that some countries are restricting the use of social media. Cybercrime is committed by individuals or small groups, as well as by criminal organizations that are often spread around the world and committing crimes on an unprecedented scale. Cyber law is the law that includes a variety of issues related to the internet and other communication technology, including intellectual property, privacy, freedom of expression, and jurisdiction. Exploring Knowledge!

184 New Gateway to Computer Science Book-8 The history of computer ethics was started from 1950 AD. Computer ethics is a branch of applied science. Computer ethics deals with how the computer experts should make decision regarding the social and professional behaviour while working with the computer tools and technology. Cybercrime is a criminal activity committed with the help of computer and computing tools. Cyber terrorists use computer tools to steal the personal information, spread viruses, hacking the web site and blogs to earn money. The growth of the internet is increasing the volume of cybercrime activities. These days people are also using social media to commit the criminal activities. Cybercrime is committed by individuals or small groups, as well as by criminal organizations. Quick Learn The following are the crime related to computer Piracy Piracy is the unauthorized distribution, theft, reproduction, copying, storage, or other use of intellectual property protected under copyright law. In computing, software piracy is a global issue. When a software program is illegally copied, downloaded or installed, a pirate commits an act of theft. Pirates engage in any activities like using, distributing or copying software illegally, uploading or downloading online music illegally, etc. Hacking A hacker is a person who finds and exploits the weakness in computer system and networks to gain access. Hackers are the computer programmers with knowledge of computer security. A computer hacker is any skilled computer expert that uses his/her technical knowledge to overcome a problem. Cyber terrorism Cyber terrorism can be explained as internet terrorism. With the beginning of the internet, individuals and groups are misusing the privacy to threaten individuals, certain groups, religions, ethnicities or politics. Cyber terrorism is defined as attack against a computer system, computer data, programs and other information.

185 New Gateway to Computer Science Book-8 Cyber stalking It is a criminal practice where an individual uses the Internet to systematically harass or threaten someone. This crime can be perpetrated through email, social media, chat, messaging and any other online medium. Cyber stalking is one of several cybercrimes that is enabled by the Internet. Spam Spam is an e-mail sent to thousands or millions of people without prior approval. The first spam e-mail was sent by Gary Thuerk on May 1, 1978. Spam is an electronic junk mail or junk newsgroup postings. A spammer typically sends an email to millions of email addresses, with the expectation that only a small number will respond or interact with the message. Cyber Law Cyber law is the part of the legal system that deals with the Internet, cyberspace, and their respective legal issues. Cyber law is a term that captures the legal issues related to use of the computer and internet technology. Cyber laws prevent or reduce the damage from cybercriminal activities by protecting information access, privacy, communications, intellectual property (IP) and freedom of speech related to the use of the Internet, websites, email, computers, cell phones, software and hardware, such as data storage devices. Social media related cybercrime in Nepal includes using pornography content in social media or creating fake profiles to intentionally harm someone with the use of Facebook, Twitter, Instagram or any social media platform. Area of cyber law Computer Crime law Computer crime law deals with the board range of criminal offenses using a computer or any computing devices. Most of the computing related criminal activities are being increased with the massive uses of internet. Computer crime is an illegal activity carried out by the use of computers and computing devices. To stop such types of criminal activities, computer crime law is important. Intellectual Property law Intellectual properties are the works done by the own creativity of an individual or the creation of mind, such as inventions, literary , artistic works, designs and symbols, names and images, etc. Intellectual property law deals with the rules for securing and

186 New Gateway to Computer Science Book-8 enforcing legal rights to writers, inventors, designers, artists, etc. This law protects ownership of personal property or organizational property. It includes copyrights, patents, trademark and industrial design. Data Protection and Privacy Law Data protection and privacy means the proper maintenance of security of information or data from being theft or from the unauthorized access. This law helps the people to maintain the proper security of data and punish those people who enter into other’s system without permission or authority. Copyright law Copyright is a form of intellectual property protection provided by the law. Copyright protection is available for original works of authorship that are fixed in a tangible form, whether published or unpublished. The copyright act prevents the unauthorized copying of a work of authorship or others. Nepal government also use this law as a part of cyber law. Trademark law A trademark is a word, symbol, or phrase, used to identify a particular manufacturer or seller’s products and distinguish them from the products of other. Trademarks make it easier for consumers to quickly identify the source of a given goods. For example instead of reading the print on a coke bottle, consumers can look for the Coca-Cola trademark. Trademark law is also included in cyber law. Telecommunication law Telecommunication is the way of exchanging the information over significant distances by electronic means and refers to all types of voice, data and video transmission. It includes a wide range of information transmitting technologies such as telephones (wired and wireless), microwave communications, fibre optics, satellites, radio, television broadcasting, internet, etc. The use of telecommunication services are rapidly increasing day by day. People may commit criminal activities with the help of telecommunication services. To stop such types of criminal activities, telecommunication law is introduced in cyber law. Cyberspace is the electronic medium of computer networks, in which online communication takes place. Cyberspace is a very wide term that includes: computers, computer networks, the Internet data software, etc. Exploring Knowledge!

187 New Gateway to Computer Science Book-8 Cyber law in Nepal The first cyber law of Nepal was introduced on Bhadra 30, 2061, which was named as Electronic transaction and digital signature act ordination- 2061. In 2063 BS “electronic transaction act 2063” and in 2064 BS “electronic transaction regulation 2064” was launched. Nepal is a developing county. The ICT sector is also in developing phase like other sectors. Nowadays the business sector, government sector and public sector are using ICT as a major tool to support all types of business process and providing services to the public. It is very essential to legalize the digital activities like online work to make it useful and standard. Computer users, and the growth of technology has resulted the use of computers for cybercrime. Most Nepalese use computers and internet for entertainment purpose and are not aware of the risk they are involved in. They probably do not have the knowledge of cyber security. The history of computer ethics was started from 1950 AD. Computer ethics is a branch of applied science. Computer ethics deals with how the computer experts should make decision regarding the social and professional behaviour while working with the computer tools and technology. Cybercrime is a criminal activity committed with the help of computer and computing tools. Cyberstalking is a criminal practice where an individual uses the Internet to systematically harass or threaten someone. Spam is an e-mail sent to thousands or millions of people without prior approval. Cyber law is the part of the legal system that deals with the Internet, cyberspace, and their respective legal issues. Computer crime law deals with the board range of criminal offenses using a computer or any computing devices A trademark is a word, symbol, or phrase, used to identify a particular manufacturer or seller’s products and distinguish them from the products of other. Quick Learn

188 New Gateway to Computer Science Book-8 1. Fill in the blanks with suitable words. a. Computer …………… is a branch of applied science. b. …………… is a criminal activity committed with the help of computer and computing tools. c. These day people are also using …………… to commit the criminal activities. d. ………… is the unauthorized distribution, theft, reproduction, copying, storage, or other use of intellectual property protected under copyright law. e. …………are the computer programmers with knowledge of computer security. f. A …………. is any skilled computer expert that uses his/her technical knowledge to overcome a problem. g. …………… it is a criminal practice where an individual uses the Internet to systematically harass or threaten someone. h. ………….. is the part of the legal system that deals with the internet, cyberspace, and their respective legal issues. i. A ………………… is a word, symbol, or phrase, used to identify a particular manufacturer or seller’s products and distinguish them from the products of other. 2. State whether the following statements are true or false. a. The history of computer ethics was started from 2000 AD. b. Cyber terrorists use computer tools to steal the personal information, spread viruses, hacking the web site and blogs to earn the money. c. The growth of the internet is decreasing in the volume of cybercrime activities. d. Cybercrime is committed by individuals or small groups, as well as by criminal organizations. e. A programmer is a person who finds and exploits the weakness in computer systems and networks to gain access. f. Cyber Crime can be explained as internet terrorism. g. Spam is an e-mail sent to thousands or millions of people without prior approval. EXERCISE

189 New Gateway to Computer Science Book-8 3. Write very short answer to the following questions. a. When was the history of computer ethics started? b. Write any one commandment of computer ethics. c. Is cybercrime a criminal activity? d. Who are called hackers? e. When was cyber law introduced in Nepal? f. Write any one area of cyber law. 4. Write short answer to the following questions. a. What do you mean by computer ethics? b. Write any six provisions of computer ethics. c. What is cybercrime? Is hacking is a cybercrime? d. Explain about Cyber terrorism. e. Define cyber law with its area. 5. Write long answer to the following question. a. Explain the area of cyber law in detail. b. What are various crimes related to computer? Explain each of them. Project Work & Activity • Conduct a presentation competition about the cyber law of Nepal and its provisions. • Prepare a chart paper with the provisions of computer ethics defined by the Computer Ethics Institute.

190 New Gateway to Computer Science Book-8 Introduction A computer virus is a manmade destructive computer program that can copy itself and infect a computer without the permission or knowledge of the user. It is also called program or piece of code that is loaded onto your computer without your knowledge and runs against your wishes. Viruses can also replicate themselves. When the virus is executed, it spreads by copying itself into or over data files, programs, or boot sector of a computer’s hard drive. Most of the computer viruses will delete data, overwrite information, display messages, and add itself to other files on the computer. Almost all computer viruses only damage the data contained on the computer and do not physically harm the computer or its hardware. I love you, Code Red, Melissa, Sasser, Zeus, Conficker, Mydoom, CryptoLocker, Flashback, etc. are the popular computer viruses. The common types of computer viruses are listed below. Types of viruses The various types of computer viruses are explained below. Computer Virus 13 Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • define computer virus and its types. • tell the symptoms of virus infection, protection mechanism. • write about the anti virus program with examples. The term ‘computer virus’ was first formally defined by Fred Cohen in 1983 Exploring Knowledge!

191 New Gateway to Computer Science Book-8 Macro Virus These are the particular type of file virus written in the macro language used to damage the software applications like word processors. A macro is a series of commands that automatically triggers a specific function within a software program. An example of this type of virus is the Melissa Virus from 1999. The macro virus is initially embedded in one document or a few documents, but it can spread to other documents within the same computer, as well as reaching out to other computers through shared documents. Boot Sector virus A boot sector virus infects the boot sector on hard disk, floppy disk and also bootable media such as CD and DVD. Bootable and non-bootable media can spread a boot sector virus. Once the infected computer successfully boots, the boot sector virus stays in memory and infects storage media when they are written to by the infected computer. These viruses infect the master boot record, they are very difficult to remove. C-Brain, Stone, Disk killer, Polyboot, etc. are the examples of boot sector virus. File infector virus File infector virus is also known as parasitic virus that usually infects memory and executable files. It is a type of computer virus that inserts its malicious code into executable files on a system. When the infected file is opened or used, the virus may overwrite the file and cause permanent damage to the content of the overwritten file. This type of virus targets a large range of operating systems, including Macintosh, UNIX, DOS, and Windows. Once they are in system they remain for a long time. Jerusalem, cascade, etc. are the examples of file infector virus. Polymorphic virus A polymorphic virus is a computer virus that affects data types and functions. It is a self-encrypted virus designed to avoid detection by a scanner. The polymorphic virus duplicates itself by creating usable, albeit slightly modified, copies of itself. The first known polymorphic virus (1260) was written by Mark Washburn in 1990. Polymorphic viruses change with each infection. Polymorphic viruses are complicated computer viruses that attack computer data types and functions. Each polymorphic virus duplicates itself into millions of copies. Evil, Elkers, Stan Bug, etc. are the examples of polymorphic virus. The Creeper virus was first detected on ARPANET, the forerunner of the Internet, in the early 1970s. Creeper was an experimental self-replicating program written by Bob Thomas in 1971. Exploring Knowledge!

192 New Gateway to Computer Science Book-8 Multipartite virus A multipartite virus is a fast-moving virus that uses file infectors or boot infectors to attack the boot sector and executable files simultaneously. The multipartite virus can affect both the boot sector and the program files at the same time. A multipartite virus infects computer systems many times and differently. The first multipartite virus was the Ghostball virus. It was discovered by FridrikSkulason in 1989. To sum up, we can say that multipartite viruses have dual capabilities and typically infect both system sectors and files. Script virus These types of viruses are created with the help of scripting languages such as VB Script, Java Script, etc. Script viruses use email to send themselves to others is also a form of worm. A Script Virus usually comes from web page advertisements, so it can spread very fast. Almost all Script Viruses have these common features: attaching itself script and being written via a scripting language such as Java Script. A Script Virus is spread via web pages and has several properties such as being easy to program, malicious, and highly transferable. Stealth virus A computer virus that actively hides itself from the antivirus software and create a copy of itself in another location on the drive are stealth virus. A stealth virus will hide itself in the system memory every time when a program scanner is run. It employs various techniques to hide any changes so that when the scanner looks for altered sections, the virus redirects it to any area that contains the clean, uninfected data. A more advanced anti-virus program can detect a stealth virus by searching for evidence of changes within system sectors along with areas that are more susceptible to attack, regardless of how it is booted. In March of 1999, hackers released the Melissa Virus, which was very powerful that it forced Microsoft and other companies to completely turn off their email systems so they could destroy it completely Exploring Knowledge!

193 New Gateway to Computer Science Book-8 A computer virus is a manmade destructive computer program Most of the computer viruses will delete data, overwrite information, display messages, and add itself to other files on the computer. I love you, Code Red, Melissa, Sasser, Zeus, Conficker, Mydoom, Crypto Locker, Flashback, etc. are the popular name of computer virus. A macro is a series of commands that automatically triggers a specific function within a software program. A boot sector virus infects the boot sector on hard disk, floppy disk and also bootable media such as CD and DVD. File infector virus is also known as parasitic virus that usually infects memory and executable files. The polymorphic virus duplicates itself by creating usable, albeit slightly modified, copies of itself. The first known polymorphic virus (1260) was written by Mark Washburn in 1990. The multipartite virus can affect both the boot sector and the program files at the same time. A script virus usually comes from web page advertisements so it can spread very fast. A stealth virus will hide itself in system memory every time a program scanner is run. Quick Learn Symptoms of virus infection. Computer will be slow down and does not respond properly. Computer will restart itself. Unwanted error message appears on the display screen. Programs and files may disappear from the computer system. Disk and drive may not open properly. Antivirus program may not work properly or may disappear from the system.

194 New Gateway to Computer Science Book-8 Protection from computer virus Always use antivirus program on your computer system and update it regularly. Scan removable storage media with antivirus before using it. Use firewall system. Do not download unnecessary software and data from the internet. Do not open unwanted and junk emails. Give priority to use genuine software programs. Routes of virus transformation Email attachment and web documents Removable storage devices like pen drive, memory card, etc. Fake websites Bluetooth, Xender, etc. Antivirus software Antivirus programs are utility tools used to detect and remove the virus from the computing devices. Most antivirus programs include both automatic and manual scanning capabilities. The automatic scan checks the files that are downloaded from the Internet, discs that are inserted into the computer, and files that are created by software installers. The automatic scan also scans the entire hard drive on a regular basis. Some special functions of antivirus software are listed below. It scans specific files or directories for any malware or known malicious programs. It allows us to schedule scans to automatically run. It allows us to initiate a scan of a specific file, storage media or computer at anytime. It removes malicious codes that are detected. Some popular antivirus programs Norton antivirus Kaspersky antivirus McAfee antivirus NOD 32 antivirus AVG antivirus Panda antivirus

195 New Gateway to Computer Science Book-8 When your computer is affected by the virus, it will slow down and does not respond properly, restart itself, unwanted error message appears and programs and files may disappear from the computer system. To protect the computer system from the virus always use antivirus program and update it regularly, scan removable storage media with antivirus and use firewall system. Email attachment, web documents, removable storage devices like pen drive, memory card, etc. and Fake web sites are the routes of virus transformation. Antivirus programs are utility tools used to detect and remove the virus from the computing devices. Most antivirus programs include both automatic and manual scanning capabilities. Norton, Kaspersky, McAfee, NOD 32 antivirus, Avira, A-vast are the popular antivirus programs. Quick Learn 1. Choose the correct option from the given alternatives. a. Which of the following is destructive computer program? i. Virus ii. Antivirus iii. Both (i) and (ii) b. Which of the following is a computer virus? i. Code Red ii. I Love you iii. Both (i) and (ii) c. Which of the following is a boot sector virus? i. C-Brain ii. Script Virus iii. Mydoom d. Which of the following is a symptom of virus infection? i. Computer restarts time and again ii. Errors messages appear on the desktop iii. Both (i) and (ii) e. Which of the following is an antivirus program? i. McAfee ii. Presentation Program iii. Mydoom EXERCISE

196 New Gateway to Computer Science Book-8 2. Fill in the blanks with suitable words. a. A …………... is a series of commands that automatically triggers a specific function within a software program. b. File infector virus is also known as ……………. that usually infects memory and executable files. c. The first known polymorphic virus was written by …………….. in 1990. d. The …………….. can affect both the boot sector and the program files at the same time. e. When your computer is affected by ……………….. it will slow down and does not respond properly. f. Email attachment, web documents, removable storage devices like pen drive, memory card, etc. and fake websites are the ………….. of virus transformation. g. Most ……………. include both automatic and manual scanning capabilities. h. Norton, Kaspersky, McAfee, NOD 32 antivirus, Avira, A-vast are the popular ……… programs. 3. State whether the following statements are true or false. a. A computer virus is a manmade destructive computer program. b. Code Red, Conficker, Crypto Locker, Flashback, etc. are the popular names of computer antivirus. c. A file infector virus infects the boot sector on hard disk, floppy disk and also bootable media such as CD and DVD. d. The polymorphic virus duplicates itself by creating usable, albeit slightly modified, copies of itself. e. A boot sector virus usually comes from web page advertisements so it can spread very fast. f. A stealth virus will hide itself in system memory every time a program scanner is run. g. To protect the computer system from the virus always use antivirus program and update it regularly. h. Antivirus programs are utility tools used to detect and remove the virus from the computing devices.

197 New Gateway to Computer Science Book-8 4. Write down a single technical term for the following. a. These are the utility tools used to detect and remove the virus from the computing devices. b. It is a series of commands that automatically triggers a specific function within a software program. c. A type of computer virus that inserts its malicious code into executable files on a system. d. These types of viruses are created with the help of scripting languages such as VB Script, Java Script, etc. e. The virus can affect both the boot sector and the program files at the same time. 5. Write very short answer to the following questions. a. Name any three computer viruses. b. Write any two examples of file infector virus. c. Name any two routes of virus transformation. d. Does computer virus affect computer hardware? e. What should be installed in your computer system to protect it from computer virus? f. Name any two antivirus that you know. 6. Write short answer to the following questions. a. What is a computer virus? Explain with examples. b. What are the types of viruses? List out them . c. What are the symptoms of virus infections? d. What are the routes of virus transformation? e. Define antivirus with some examples. f. Explain the ways to protect your computer system from the viruses. 7. Write long answer to the following question. a. Explain the types of computer viruses. Project Work & Activity • Conduct a presentation competition about the symptoms of computer virus and protecting mechanism. • Use any antivirus software that has been installed in your computer system and scan D: drive of your hard disk.

198 New Gateway to Computer Science Book-8 Introduction People need to communicate electronically in today’s world. They need to exchange data and information with one another. A good communication system is a must for every individual and organization. Most of the organizations depend on interconnected networks of computers to service their processing needs. A computer network is a group of two or more than two computers that are linked together to share the information and resources. Generally, computer network is any arrangement where a sender transmits a message to a receiver over a channel consisting of some type of medium. A computer network is a set of computers connected together for the purpose of sharing resources. We need sender, receiver, communication channel, protocols and operating system to establish a computer networking. Uses of computer networking Resource sharing like file, data, storage devices, hardware, software and some application programs. It is used for providing high reliability. Introduction to 14 Computer Networking Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • define compuetr network with its advantages and disadvantages. • identify the components required for networking. • explain the types of computer networking. • tell about network topology. • write about network architecture.

199 New Gateway to Computer Science Book-8 It can provide a powerful communication medium like e-mail, messaging, VOIP, etc. It is very cheaper system. Advantages of networking It enhances communication and availability of information. It allows for more convenient resource sharing. It makes file sharing easier. It has a highly flexible working condition. It increases cost efficiency Disadvantages of networking It is difficult to establish Trained person is required to handle. It has less privacy. More chances of spreading viruses. Components for computer networking Computer: It is the most essential component to establish networking system. A computer can act as a server, host or client in the networking system. It is almost impossible to establish computer networking without the computer system. Network Interface Card (NIC): Network Interface Card is also called as LAN (Local Area Networking) card. It connects the computer to the cabling, which creates links with all of the computers on the network together. Each computer on a network must have a network card. The network interface card is built in with motherboard in every desktop and laptop computers. Communication Media: Guided and unguided media are used in networking as a communication media. Guided media use wire or cable technology and unguided media use wireless technology like WIFI to create networks. Port can be referred as logical channel through which data can be sent/received to an application. Any host may have multiple applications running, and each of this application is identified using the port number on which they are running on. Exploring Knowledge! Computer networking is an act of connecting or joining two or more computer devices like the desktop, laptops, tablet PC, smartphones, etc. together to share files and resources, working remotely to achieve targeted aim and purpose. Exploring Knowledge!