Unit 2.1

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Unit 2.1

  1. 1. Programming and Development Tools Web Programming UNIT 2.1Web ProgrammingInternet Basics OBJECTIVES This unit helps you to be familiar with the fundamentals of Internet and to explore the World Wide Web. At the end of this unit, you will be able to Connect your computer to the Internet Search the www effectively Identify the uses of Internet Browse the Internet Send E-mail Use the browser efficiently Identify IP Address and URLBenchmark standard Browse the Internet effectively. Use the WWW resources proficiently. Demonstrate the Web server concepts.Internet Basics 2.1-1
  2. 2. Programming and Development Tools Web ProgrammingIntroductionIs it possible to wrap the earth? Yes, Internet makes the Earth so small bywrapping it up with the communication media as shown in Figure 2.1.1. Figure 2.1.1: Earth wrapped by communication mediaYou know that Wide Area Network (WAN) is a network that connectscomputers and devices over a large area. There are innumerable WANs allover the world. These WANs are interconnected throughout the world to formInternet. Hence, Internet is a global network of networks. It connects a widevariety of computers and millions of users all over the world. You can use theInternet services to send messages, chat with your friends, gather informationon any topic, access a remote computer, transfer files from one computer toanother and much more.2.1.1 Getting connected to InternetSuppose that your English teacher gives you an assignment to collect a wordand its meaning every day. You can go to a library and search for a word in thedictionary. But the easiest way is to use the Internet. You can use the Internetto get the word, just on a mouse click. TipMake a habit of browsing the Internet to collect at least a word and its meaning everyday. Hands-On!Find the word of the day and its meaning using the site www.dictionary.com.The steps for getting the word of the day from the site www.dictionary.com aregiven below: 1. Double-click the Internet Explorer icon on the desktop to open Internet Explorer. 2. Type www.dictionary.com in the Address bar and press the Enter key. 3. Click the Word of the Day hyperlink.Internet Basics 2.1-2
  3. 3. Programming and Development Tools Web Programming 4. Note down the word of the day and its meaning.Now you will have these questions in mind. What are the minimumrequirements to have Internet connection? How is your computer connected toother computers on the Internet? What type of connection is feasible? Howdoes your computer display a page that is stored in some other machinelocated somewhere in the world? All your questions will be answered in thefollowing sections.Requirements to get Internet ConnectionThe following are the minimum requirements to have an Internet connection: 1. A computer with the following configuration: Processor : 486/66 MHz Processor Memory : 16 MB RAM Video card : 640 X 480 resolution 256 colors 2. A telephone line 3. A MODEM (Modulator and De-modulator). 4. An ISP (Internet Service Provider). 5. A Web Browser : Commonly used browsers, Internet Explorer or Netscape Navigator. NoteA Web browser is software used to display a Web page.Internet Explorer is the browser used for examples throughout this module. NoteAn Internet service providing (ISP) company allows you to use their Internet connection bypaying the amount specified by them. On payment, ISP gives you a user name, password, anaccess telephone number and a dial-up program to connect your PC to the Internet.Types of Internet ConnectionThere are different ways of connecting your computer to the Internet. Thedifferent types of connections are: Dial-up connection Broadband cable DSL and ISDN Wireless connectionInternet Basics 2.1-3
  4. 4. Programming and Development Tools Web ProgrammingDial-up ConnectionIndividual users and small companies prefer dial-up access, because it is aneasy and less expensive way of connecting to the Internet. The speed ofInternet access in this type of connection is less than 56 kbps (kilobytes persecond). In this connection, the MODEM in your computer is connected to theInternet by using a standard telephone line. To get a dial-up connection, set upan account with your ISP. Your ISP will provide you a program in CD-ROM, ausername and a password.After getting these requirements from the ISP, connect the telephone cable toyour PC and install the program in your computer. Now you are ready toaccess the Internet. With these, you can connect your PC with the Internet.You can connect and disconnect your computer to the Internet, whenever youwant. NoteA MODEM is a device that converts analog signals (signals that can be carried throughtelephone cables) into digital signals (signals that a computer can understand) and vice-versa.Broadband CableIn the broadband cable connection, the MODEM in your computer is connectedto the Internet through a cable TV line. The speed of Internet access in thistype of connection is around 1000 kbps, which is faster when compared to thedial-up connection. Here, your computer is connected to the Internet 24 hours aday. You can browse the Internet and at the same time watch the TV.DSL and ISDNIn Digital Subscriber Line (DSL) and Integrated Services Digital Network(ISDN), your computer is connected to the Internet through a copper telephoneline. With this connection, you can use the telephone and browse the Internetat the same time. In this type of connection also your computer is connected tothe Internet 24 hours a day. The errors are less while transmitting and hencethe speed of Internet access is faster (around 1000 kbps) in this type ofconnection.Wireless ConnectionNowadays, Wireless Internet access technologies are also popular. This type ofconnection is used to connect Internet with PDAs, notebook computers andsmart phones. A wireless connection is established using satellite and cellularradio network. These are faster than dial-up connections.Connecting to the InternetThe following are the steps to connect and disconnect your computer from theInternet, using a Dial-up connection:Internet Basics 2.1-4
  5. 5. Programming and Development Tools Web Programming 1. Double-click the dial-up program’s icon on the desktop. Dial-up icon Figure 2.1.2: Dial-up Icon on the DesktopThe Connect dialog box appears as shown in Figure 2.1.3. Rabiah Figure 2.1.3: Connect Dialog Box 2. In the Connect dialog box, type the username, password and dial number provided by the ISP. Click the Dial button. If the informationInternet Basics 2.1-5
  6. 6. Programming and Development Tools Web Programming provided is correct, your computer will be connected to the Internet and a connection icon appears on the taskbar. Connection icon Figure 2.1.4: Connection Icon on the Desktop 3. To disconnect, click the Connection icon at bottom-right corner of the task bar. The Status dialog box appears as shown in Figure 2.1.5. Click the Disconnect button. Figure 2.1.5: Status Dialog BoxInternet Basics 2.1-6
  7. 7. Programming and Development Tools Web Programming Self-Check Exercise 2.1.11. Identify what type of Internet connection, you require for the following conditions: Speed of Internet access does not matter to you. You do not want to connect to the Internet 24 hours a day. You do not have a cable TV connection at your home. You have a telephone line.2. Identify the false statement in the following set of statements: A wireless connection is established using satellite and cellular radio network. In Broadband Cable connection, you can browse the Internet and watch TV at the same time. Digital Subscriber Line is the expansion of DSL. The speed of Internet access is greater in Dial-up connection when compared to other connections. Activity 2.1.11. Browse the Internet and find the meanings of the following terms: Cybrarian Cybercafe Cybercitizen e - paper Electronic resume2.1.2 World Wide WebWorld Wide Web (www) is an Internet service that provides worldwideinformation with a vast collection of Web sites.Suppose that you are on summer holidays and want to visit some fascinatingplaces in Malaysia. You can browse the Internet to collect information aboutsome interesting places of visit in Malaysia and enjoy your summer holidays. Hands-On!To search for the information about the places of visit in Malaysia, 1. Click the Internet Explorer icon on the desktop and open the Internet Explorer. For example, you can type www.geographia.com in the Address bar and press the Enter key. The home page of the Web site www.geographia.com is displayed in the browser window as shown in Figure 2.1.6.Internet Basics 2.1-7
  8. 8. Programming and Development Tools Web Programming Figure 2.1.6: Home Page of geographia.com 2. Click the Asia hyperlink to open the linked page as shown in Figure 2.1.7. Figure 2.1.7: A Sample Web Page of geographia.comInternet Basics 2.1-8
  9. 9. Programming and Development Tools Web Programming 3. Click the hyperlink, Malaysia in this Web page and select the hyperlink Places to view the page containing information about tourist spots in Malaysia. Figure 2.1.8: A Sample Web Page of geographia.comYou have seen some of the Web pages of the Website geographia.com thatcontain information about the tourist spots. These are just a few sample Webpages out of the millions posted in the Web. World Wide Web shortly www is ahuge collection of such Web pages. Figure 2.1.9 shows that information isspread over the world like a Web using Internet. Figure 2.1.9: World Wide WebInternet Basics 2.1-9
  10. 10. Programming and Development Tools Web ProgrammingA Web page is an electronic document that contains information in the form oftext, pictures, audio or video. A Web site is a collection of such related Webpages. In geographia.com, you have seen some Web pages that have relatedinformation. The Web pages of a Web site are linked together by hyperlinks. InFigure 2.1.8, you can see the link, Places that is used to open another Webpage, about the various places of visit in Malaysia. The first page of a Web siteis called Home page. Figure 2.1.6 shows the home page of the web sitewww.geographia.com.Searching the WebSearching the Web for information spread across the globe is as easy assearching for a file in your computer. You can get information, specific to anyfield, from the Web in just a few mouse clicks. Figure 2.1.10: Searching the WebYou can plan for your higher studies by collecting information such as thecolleges available in Malaysia, courses and facilities offered by differentcolleges. There are many sites that provide you this information. Search for thesites on the Web using the search engines. NoteA Search Engine is a program used to search the Web for related Web pages.The steps to search for information using search engines are given as follows:Step 1: Open Internet Explorer and type www.google.com.my in the Address bar and press the Enter key. The home page of the Web site, www.google.com.my is displayed in the browser window as shown in Figure 2.1.11.Internet Basics 2.1-10
  11. 11. Programming and Development Tools Web Programming Figure 2.1.11: Home Page of google.comStep 2: Type the keywords Malaysia colleges in the text box and click Google Search button. The links of Web pages that contain the keywords Malaysia and colleges are displayed on the screen as shown in Figure 2.1.12. Click any of these links to view the Web pages related to your search information.Internet Basics 2.1-11
  12. 12. Programming and Development Tools Web Programming Figure 2.1.12: Result of a sample search in google.comThere are different ways of searching and there are different search engines tosearch the Web. Some of the famous search engine addresses are: www.google.com www.altavista.com www.alltheweb.com www.excite.com www.hotbot.com www.lycos.com www.yahoo.comSearching TechniquesIf you want to collect information about the different colleges in Malaysia, thenyou can use the keywords Colleges and Malaysia. You can specify these twokeywords in different ways in the Search textbox and vary the searchingtechnique accordingly. For example, open www.yahoo.com and type the keywords within quotation to search for the pages that contain the keywords given in the same order as mentioned in the Search textbox. For example, the keywords Colleges in Malaysia will search for the Web pages that contain the 3 keywords appearing in the same order.Internet Basics 2.1-12
  13. 13. Programming and Development Tools Web ProgrammingType the keywords without quotation to search for the pages that contain thekeywords in any order. For example, the keywords Colleges in Malaysia willsearch for the Web pages that contain the 3 keywords appearing in any order. Use Boolean Logic in your search. You can use the Boolean logic that combines the keywords using Boolean Operators in your search. The different Boolean Operators are AND, OR and NOT. The AND operator searches for the pages on the Web that contains both the keywords in the Search textbox. For example, the keywords combined using AND operator as Colleges AND Malaysia makes the browser search for the pages that contain both the words, Colleges and Malaysia as shown in Figure 2.1.13. Web pages Web pages containing containing only Colleges only Malaysia Web pages containing both Colleges & Malaysia Figure 2.1.13: Search Result using AND Operator The OR operator searches for the pages on the Web that contains either one of the keyword or both the keywords. For example, the keywords combined by the OR operator as Colleges OR Malaysia searches for the pages that contain either Colleges or Malaysia or both as shown in Figure 2.1.14.Internet Basics 2.1-13
  14. 14. Programming and Development Tools Web Programming Web pages Web pages containing containing only Colleges only Malaysia Figure 2.1.14: Search Result using OR Operator The NOT operator makes the browser search for the pages that does not contain the search keyword given after NOT. For example, the keywords combined using NOT operator as Colleges NOT Malaysia make the browser search for the Colleges that are not in Malaysia as shown in Figure 2.1.15. Web pages Web pages containing containing only Colleges only Malaysia Web pages containing both Colleges & Malaysia Figure 2.1.15: Search Result using NOT Operator NoteThe working of NOT operator varies slightly among various search engines.You know that the storage capacity of a disk is measured in bytes. Do youknow how many Kilobytes make 3 Gigabyte? The following example uses asearch engine to search for the Web pages that provide this kind of information.Here, you have to search for pages online that have details about conversionsrelated to computer. So, the keywords that can be used to search may be thecombination of the words Online, Conversion and Computer. Hence thekeyword for the search will be Online AND Conversion AND Computer.Internet Basics 2.1-14
  15. 15. Programming and Development Tools Web Programming Hands-On!Open a search engine, say www.google.com and type Online AND ConversionAND Computer in the text box and click Google Search button. The links ofpages that contain the words Online, Conversion and Computer are displayedas shown in Figure 2.1.16. Figure 2.1.16: Search result using google searchClick on a link and get your information. Self-Check Exercise 2.1.2Fill in the blanks:1. A ________ is an electronic document that contains information in the form of text, pictures,audio and video.2. The first page of a Web site is called _________.3. _______ is an example for a search engine.4. WWW is the acronym for _______.5. The Boolean operators that can be used in searching are ____, ____ and ____.Internet Basics 2.1-15
  16. 16. Programming and Development Tools Web Programming Activity 2.1.2Search for the Web sites that provide information about the different ISPsavailable in your region. Lab ExerciseLab Exercise 1: Find out the list of universities in Malaysia using google search.Lab Exercise 2: Find out the information about Petronas Twin Tower using any search engine.Lab Exercise 3: Search the Web to find information about the World Cup Football Winners till now.Lab Exercise 4: Search the Web sites to find information about the best Football players in the world.Lab Exercise 5: Browse the Web for finding the details about Bachelor of Computer Science Programme in the various colleges of Malaysia.Lab Exercise 6: Find out the USA International dialing code using search engine.Lab Exercise 7: Search the Web using a search engine to find “Information about Internet” with and without double quotation marks and find the difference.Lab Exercise 8: Search the Web page for “Tours and Travels in Malaysia” using the Yahoo search engine. Use the Boolean operators “or”, “not” instead of “and” in the search string and find the difference.Lab Exercise 9: Collect the information about “Festivals in Malaysia” and document the information.2.1.3 Uses of InternetGathering information is one of the main uses of Internet. You can collectinformation almost on any topic using the Internet. Apart from its use as a bestcommunication media, Internet has also grown as an educating andentertainment medium. Apart from these, Internet provides some vital serviceslike E-mail, FTP, and Newsgroup.E-mailElectronic mail (E-mail) is one of the major uses of the Internet. You can sendand receive messages to the users all around the world using the e-mailprogram. Here, the procedure for sending mail is explained using the yahoo E-mail service.To send an e-mail, follow the steps given below:Step 1: Open Internet Explorer. Type www.yahoo.com in the Address bar. The home page of yahoo is displayed on the screen.Internet Basics 2.1-16
  17. 17. Programming and Development Tools Web Programming Click here to Sign In Figure 2.1.16: Home page of yahoo.comStep 2: Click the hyperlink Sign In. The page shown in Figure 2.1.17 is displayed in the Web browser. Figure 2.1.17: Sign in Page of yahoo.comInternet Basics 2.1-17
  18. 18. Programming and Development Tools Web ProgrammingStep 3: Enter your ID and Password in the respective text boxes provided and press the Enter Key. Your ID and password are checked and the Web page shown in Figure 2.1.18 is displayed. Mail hyperlink Figure 2.1.18: Home page of yahoo.comStep 4: Click the Mail hyperlink. Select Compose in the page displayed. The page shown in Figure 2.1.19 is displayed. Figure 2.1.19: Compose Page of yahoo.comInternet Basics 2.1-18
  19. 19. Programming and Development Tools Web Programming To: In the To text box, type the receiver’s e-mail address. Cc: In the Cc text box, type the e-mail addresses of the persons to whom you want to send a copy of the same message. Cc stands for Carbon Copy. Bcc: Bcc stands for Blind Carbon Copy. Bcc is similar to Cc, but the difference is that the users specified in the Bcc text box will receive the message without the knowledge of the users specified in the To and Cc text boxes. Subject: Type the subject of the message in the Subject text box. Attach Files: Click Attach Files hyperlink to attach a file with that message. Select the file you want to attach and click OK.Step 5: Type the body of the message in the large text box and click the Sendbutton.To view the mails that you receive, follow the steps given below: Step 1: Open www.yahoo.com and select Mail hyperlink. Step 2: Enter your username and password in the Sign In page. Step 3: Click the Inbox hyperlink. Step 4: Click the mail you want to read. NoteAll the mails you receive will be stored in the Inbox. Activity 2.1.3Type your bio-data in Word format and send this as an attachment to your ownmail ID.E-commerceElectronic commerce shortly called E-commerce is a business that involvestransfer of information about a product, exchange of goods and services overthe Internet. Anyone who has a computer, an Internet connection and a meansto pay the money for purchased goods can buy a product through E-commerce.FTPFTP stands for File Transfer Protocol. FTP is used to transfer files over theInternet. You can upload and download your files to any place in the worldusing FTP. Uploading is the process of sending documents from your computerInternet Basics 2.1-19
  20. 20. Programming and Development Tools Web Programmingto a server. Downloading is the process of receiving documents from a serverto your computer.NewsgroupNewsgroup is an area on the Internet, where users can discuss on a particulartopic. A user can send a message to a newsgroup on a particular topic and allthe other users of that newsgroup can view and reply to that message. Thereare several newsgroups in the Internet. The collection of all newsgroups iscalled Usenet. The computer that stores and replies the newsgroup messagesis called News Server.ChatChatting is a conversation between two or more users over the Internet.Millions of people chat all over the world using Internet no matter how far theyare located. Self-Check Exercise 2.1.3Am I correct?1. Newsgroup is a feature used to transfer files over the Internet.2. FTP is a conversation between two or more users over the Internet.3. You can send and receive messages to the users all around the world using the e-mail program.4. You cannot add files to your messages using E-mail.5. E-commerce is a business that involves transfer of information about a product, exchange of goods and services over the Internet. Lab ExerciseLab Exercise 10: Send a mail to your friend.Lab Exercise 11: Send a mail with the same message to different mail address.2.1.4 Browsers and Web Server ConceptsThe browser acts as an interface between the user and the Web. It is anapplication program that resides in the client machine and displays the contentof a Web page. The browser reads the instructions given in a language such asHTML and displays the document in the browser window. Some of thebrowsers are Internet Explorer, Netscape Navigator, Hot Java, Mozilla, Mosaicand Opera. Here, you will be exposed to one of the renowned browsers, theInternet Explorer.Internet Basics 2.1-20
  21. 21. Programming and Development Tools Web ProgrammingYou can open the Internet Explorer by selecting Start Programs InternetExplorer. The Internet Explorer interface opens as shown in the Figure 2.1.20. Figure 2.1.20: Internet Explorer Interface The title bar is displayed at the top of the page. It contains the title of the document. Menu bar is displayed below the title bar. The Standard Buttons toolbar is below the Menu bar. Next to the Standard Buttons toolbar is the Address bar, where you type the URL of a particular web page. Below the address bar is the area where the document will be displayed. The status bar is displayed at the bottom of the Internet Explorer window.Opening a Web Page in Internet ExplorerTo open a Web page in Internet Explorer, type the URL of the Web page in theAddress bar and press the Enter key. For example, to open yahoo.com typewww.yahoo.com in the Address bar and press the Enter key. The home pageof yahoo.com will be displayed in the browser window.Buttons in the Standard buttons toolbarThe Back button is used to open the previous page that had been visited. TheURLs of the pages that had been visited can be viewed by clicking the smallarrow at the right of the Back button. The desired page can be viewed byclicking the URL from the list displayed.Internet Basics 2.1-21
  22. 22. Programming and Development Tools Web ProgrammingThe Forward button is used to open the next page to the current page that hadbeen visited. The URLs of the pages that had been visited can be viewed byclicking the small arrow at the right of the Forward button. The desired pagecan be viewed by clicking the URL from the list displayed.If you have typed the URL of a page in the Address bar and pressed the Enterkey, the browser will start connecting to that page. If you want to stop thesearch in the middle, click the Stop button.Sometimes the Web page you are searching for may not be displayed properly.The Refresh button can be used to restart the search from the beginning.The Web pages that you often visit can be stored in Favorites so that you canretrieve it easily in future.Home button can be clicked to get back to the home page set in the browser.Web ServerIn an earlier session, you have got a word and its meaning using the Web sitewww.dictionary.com. Two computers were involved in this process of retrievingmeaning of the word. The computer using which you sent a request is theClient Computer. The computer that received your request and responded to itis the Server Computer. Some of the servers are Web server, FTP server andmail server. Web server follows a set of rules while communicating with theclient. This set of rules is known as HTTP (Hypertext Transfer Protocol).Internet Basics 2.1-22
  23. 23. Programming and Development Tools Web Programming Request Response Client Server Figure 2.1.21: Web Server responding to a Client’s RequestThe meaning of server here is related to both hardware and software. The Website, say www.dictionary.com is stored in the server machine. The responsemade to your request is through the software. Microsoft’s IIS (InternetInformation Server) is popular Server software for Windows OS. The followingare the steps that occur while retrieving a Web page: 1. The browser breaks the URL into different parts namely, the protocol (HTTP – Hypertext Transfer Protocol), the server name and the file name. NoteThe HTTP is the set of rules followed by the server for effective communication with the client. 2. The browser sends the server name to a name server that translates the server name into IP Address. The browser uses the IP address to communicate with the server. 3. The browser sends a GET request to the server asking for the Web page. 4. The server finds the requested page and sends HTML code of page to the browser. 5. The browser reads the HTML code and displays the page in the browser window.Figure 2.1.22 visualizes the above mentioned points:Internet Basics 2.1-23
  24. 24. Programming and Development Tools Web Programming Figure 2.1.22: Server Serving a Web page to a ClientData Transmission from Client to Web ServerEstablish the Internet connection by dialing up your Internet Service Provider(ISP). After establishing the connection to the Internet, open a Web browser,say Internet Explorer by double clicking its icon on the desktop. The InternetExplorer opens with its home page. Type the address of the Web site, saywww.yahoo.com in the Address bar and press the Enter key. The Web page thatyou requested is displayed in the browser as shown in Figure 2.1.23. Figure 2.1.23: Home Page of yahoo.com The steps involved in transmitting data in the Internet are as follows:Internet Basics 2.1-24
  25. 25. Programming and Development Tools Web Programming 1. The request that you made to display the home page of yahoo by typing the address of the Web site is sent to a MODEM in the form of digital signals. 2. The MODEM connected to your computer converts the digital signals into analog signals. The telephone cables can carry only analog signals. 3. The analog signals are carried through the telephone line to a regional ISP. 4. The data in the form of signals are then passed to a national ISP through telephone lines. 5. The signals are passed to another national ISP, from where it is transferred to the regional ISP in the server location. 6. From the regional ISP, the signals are passed to the server that contains the required Web page after converting to digital signals by a MODEM. Figure 2.1.24: Data Transmission from Client to Web Server 7. The server gets the requested data (Web Page) and sends it to the client computer through the regional and national ISPs. 8. The MODEM in your location converts analog signals to digital. 9. Finally, the data received by your computer is displayed in the browser window as shown in Figure 2.1.23.Internet Basics 2.1-25
  26. 26. Programming and Development Tools Web Programming2.1.5 IP Addresses and Uniform Resource Locator2.1.5 (A) IP AddressThe computers in the Internet are linked by a network. In this network, yourcomputer acts as a client. The client computer can request different computers,which act as servers for data and information. Each computer in the network isidentified by a unique address known as IP address, short form for InternetProtocol address.The following is an example for an IP address: 103.38.123.214 Represents a Represents a specific network computer in the networkThe IP address consists of four parts. Each part is called as octet becauseeach part is made up of 8 bits (8 binary digits) and makes a total of 4 X 8 = 32bits. Each octet is a number between 0 and 255 in decimal form and isseparated by a dot. The first 3 octets represent the network to which thecomputer is connected and the fourth octet represents the computer in thatnetwork.2.1.5 (B) URLEvery Web page in WWW has a unique address. This address is called as URL(Uniform Resource Locator). The URL is similar to the postal address. Thepostal address contains your door number, street name, area name and zipcode. Similarly the URL contains protocol, domain name, path and Web pagename as shown in the following example. http://www.geographia.com/indx04.htm Protocol Domain Name Web page nameIn the above example, http is the protocol, www.geographia.com is the domainname and indx04.htm is the Web page name.In the domain name, the last portion is called top-level domain that representsthe type of organization, the Web site belongs to. Here, .com refers tocompanies and commercial organization. A list of some of the top-leveldomains is given in Table 2.1.1.Internet Basics 2.1-26
  27. 27. Programming and Development Tools Web Programming Top-Level Domains Domain Type com Commercial Organizations and companies org Non-Profit Organizations net Company that provides network gov Government Organizations edu Educational Institutions Table 2.1.1: List of Top-Level Domains Self-Check Exercise 2.1.4Who am I? (Identify who I am using minimum number of clues given below)Clue 1 - I reside in client’s computerClue 2 - Without me, you cannot see any web pages.Clue 3 - I can understand HTML tags.Clue 4 - I act as an interface between the user and the web. Technical TerminologiesInternet - Internet is a network of networksMODEM - A device that converts analog signals into digital signals and vice-versa.ISP - Internet Service provider (ISP) is a company that allows you to use their Internet connection for a price.Web Page - An electronic document that contains information in the form of text, pictures, audio and video.Web Site - Collection of related Web pages.Hyperlink - Link that connects Web pages of a Web site.Home Page - First page of a Web site.E-mail - Program used to send and receive messages to the users all around the world.E-Commerce - A business that involves transfer of goods and services over the Internet.FTP - A program used to transfer files over the Internet.Newsgroup - An area on the Internet where users can discuss on a particular topic.Internet Basics 2.1-27
  28. 28. Programming and Development Tools Web ProgrammingChat - Conversation between two or more users over the Internet.IP Address - IP Address is the address of your computer on the Internet.URL - The address of a Website is called URL (Uniform Resource Locator).PDA - Personal Digital Assistant is a hand-held computer that has a calendar and organizer for storing personal information.SummaryIn this unit, you learnt that Wide Area Networks are interconnected through out the world to form Internet. MODEM is a device that converts analog signals into digital signals and vice-versa. In Broadband cable connection, the MODEM in your computer is connected to the Internet through a cable TV line. World Wide Web shortly www is a huge collection of web pages. Web site is a collection of related Web pages. The first page of a web site is called Home page. E-mail is a program used to send and receive messages to the users all around the world. FTP is used to transfer files over the Internet. Chatting is a conversation between two or more users over the Internet. Browser is an application program that displays the content of a web Page. Each computer in the network is identified by a unique address known as IP address. Every Web page in WWW has a unique address called as URL.Internet Basics 2.1-28
  29. 29. Programming and Development Tools Web Programming AssignmentI. Solve the following crossword: 1 2 3 4 5 6 7 8 9 10Across 5. Network of Networks 7. Approach them to get Internet connection 8. Opening page of a Web site 10. Store the frequently visiting pages hereDown 1. Click this to view the related page 2. Used to transfer files 3. Interface between user and WWW 4. Collection of related web pages 6. Domain name for government organizations 9. A Web serverII. Answer the following questions: 1. Define the term Internet. 2. Mention the use of a MODEM. 3. Define the term E-commerce. 4. State the definition for a Web browser. 5. Write short notes on IP address and URL.Internet Basics 2.1-29
  30. 30. Programming and Development Tools Web ProgrammingCriterion Referenced TestInstruction: Students must evaluate themselves to attain the list ofcompetencies to be achieved.Name:Subject: Programming and Development toolsUnit: Internet BasicsPlease tick [ √ ] the appropriate box when you have achieved the respectivecompetency.Date Internet Basics C1 C2 C3 C4 C5CommentCompetency codes:C1 = List the requirements to connect your computer to the Internet.C2 = Search the WWW for information using different search techniques.C3 = List the uses of Internet.C4 = Send an E-mail.C5 = Describe how data is transmitted from client to server and vice-versa.Internet Basics 2.1-30

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