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PowerPoint Presentation to Accompany Chapter 7 The Internet Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall.

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Presentation on theme: "PowerPoint Presentation to Accompany Chapter 7 The Internet Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall."— Presentation transcript:

1 PowerPoint Presentation to Accompany Chapter 7 The Internet Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

2 Objectives 1.Recognize the importance of the Internet. 2.Compare types of Internet connections. 3.Compare popular Web browsers. 4.Demonstrate how to navigate the Web. 5.Discuss how to evaluate the credibility of information found on the Web. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

3 Key Terms Objective : Overview 1 Internet Timeline 1.Discuss the origins of the Internet 2.Discuss the impact of hypertext and hyperlinks 3.Discuss Internet2 and why it was created  ARPANET  Hyperlink  Hypertext  Internet (net)  Internet2  Internet backbone  Internet Exchange Points  World Wide Web Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

4  In 1957, the Soviet Union launched the first space satellite – Sputnik.  The United States and the Soviet Union were engaged in a political conflict – called the Cold War – at the time, and this launch led to fears that the United States was falling behind in the technology race. Brief History of the Internet

5  In 1958, President Eisenhower created the Advanced Research Projects Agency (ARPA) to jump-start U.S. technology for the military.  One of ARPA’s early projects was to create a Galactic Network that would connect smaller networks around the world. Brief History of the Internet

6  The Internet started as a U.S. Department of Defense ARPA project in the 1960s to design a communications system that had multiple pathways through which information could travel so that losing one part of the system (e.g. in a nuclear strike) wouldn’t cripple the whole thing. Brief History of the Internet

7  It took about 10 years to develop the technology.  The original system was called ARPANET and only had four nodes on it.  The University of California (UCLA)  Stanford Research Institute (SRI)  The University of Utah in Salt Lake City  The University of California at Santa Barbara (UCSB) Brief History of the Internet

8 The original drawing of the ARPANET illustrates the four nodes: UCLA, UCSB, SRI, and University of Utah

9 Brief History of the Internet In 1979, the National Science Foundation (NSF) created CSNET to connect the computer science departments at universities using the ARPANET technology. In the mid-1980s, the National Science Foundation (NSF) created NSFNET giving other academic disciplines access to supercomputing centers and connecting smaller networks together. By the late 1980s, the NSFNET was the primary Internet backbone.

10 Brief History of the Internet A backbone is the high-speed connection points between networks. In 1995, NSF decommissioned the NSF backbone. The Internet backbone was privatized. The first five large Network Access Points (NAPs) that made up the new backbone were established in Chicago New Jersey San Francisco San Jose Washington, D.C.

11 Brief History of the Internet Today, the backbone of the Internet is composed of Internet Exchange Points around the world.

12 The Internet The Physical Entity: A Network of Computers  IM  Email  VoIP  FTP  P2P  WWW Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

13 Brief History of the Internet Most people use the terms “Internet” and World Wide Web” interchangeably, but they are, in fact, two different things. The Internet is the physical entity – a network of computer networks. The World Wide Web is just one way that information moves on the Internet. Email, instant messaging, peer-2-peer (P2P), file sharing, and VoIP (voice over IP) are other ways that you might use the Internet.

14 Brief History of the Internet In 1991, Tim Berners-Lee and CERN (European Organization for Nuclear Reseach) released the hypertext system we know as the World Wide Web. The web is made up of Hypertext - text that contains links to other text or objects. Hypertext enables you to navigate through pieces of information by using the links, known as hyperlinks, that connect them. The milestone of having a million Internet nodes (networks or ISPs) was reached in 1992 and commercial sites started to appear.

15 Brief History of the Internet In 1993, a group of graduate students led by Marc Andreessen released the Mosaic point- and-click graphical browser for the Web, which later became Netscape Navigator – the dominant web browser in the 1990s. These events led to a user-friendly Internet. A couple years later, Windows 95 was released and existing online service companies such as AOL and CompuServe began offering Internet access.

16 The Internet The Physical Entity: A Network of Computers Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

17 Brief History of the Internet As personal computers dropped in price and became more powerful, the Internet grew at an incredible rate, and it had almost 3 billion users by 2014. Over the past several years, the widespread use of mobile devices such as tablets and smartphones has put Internet access in the hands of even more people.

18 Internet 2 (I2)  Colleges  Universities  Other educational institutions  Museums  Art galleries  Libraries  Hospitals Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall Designed for education, research, and collaboration

19 Internet 2 (I2) The original use of the Internet – research and education – have been overtaken by commercial and social uses. Even as bandwidth and the Internet infrastructure increase, educational and research institutions have been unable to access the speed and resources they need. Thus, the Internet2 project was born. Internet2 (I2) is a second Internet designed for education, research, and collaboration, very much like how it all began – only faster.

20 Internet 2 (I2) In 1995, when NSFNET was decommissioned, there was a small remnant retained just for research called the Very High Speed Backbone Network Service (vBNS) which later evolved into the Internet2 project. While the Internet is composed of a mix of older telephone cables and newer fiber- optics, the I2 backbone is all fiber. The data travels much faster and is less prone to corruption.

21 Internet 2 (I2) Membership in I2 is limited to colleges, universities, other educational institutions, museums and art galleries, libraries, hospitals, and other organizations that work with them. It’s a pretty small group, and that’s one of the reasons it’s so fast. Collaboration, streaming video, and Web conferencing are just some of the applications that benefit from the faster speed.

22 Does your school participate in the I2 project? Ask your librarian or instructor. If yes, what features does your school use? If not, why not? Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

23 Key Terms Objective : Overview 2 Get Connected 1.Discuss methods to connect to the Internet 2.Compare and contrast Internet connection methods 3.Discuss wireless connection methods  Broadband  Cable Internet access  Dial-up  DSL  Fiber-to-the-Home (FTTH)  Hotspot  Internet service provider (ISP)  LTE (Long Term Evolution)  Municipal WiFi  Satellite Internet access  WiFi  WiMAX Mobile Internet Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

24 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  There are many different ways to get on the Internet.  If you have a personal computer, you have several options.  Internet Service Providers (ISPs)  Companies that offer Internet access offer many different plans from which to choose.

25 Internet Connection  Internet service provider (ISP)  Dial-up  Broadband  Wireless  Wireless mobile  Satellite Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

26 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  The least expensive type of connection is usually dial-up.  With a dial-up connection, you use your regular phone lines to connect to the network.  Plans range from about $10 to $30 per month.  For some people, a dial-up connection may be the only option available.  Dial-up can be very slow, maxing out at 56 Kbps (kilobits per second).  Another drawback is that the connection ties up your phone line while you’re online.

27 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  If you’re looking for more speed, then you have several options.  Cable, DSL, FiOS, and wireless technologies.  The FCC defines broadband as anything over 200 Kbps, which is at least four times faster than dial-up.  Availability, speed, and costs vary depending on where you live.

28 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Cable Internet access is generally offered by your cable TV provider and uses the same wires to carry both signals.  Some cable companies also offer digital phone service.  This requires older cable systems to be upgraded, so it’s not universally available.  Cable speeds range from 1 Mbps to 150 Mbps but are typically 16 Mbps to 50 Mbps.  One cable drawback is that you share cable Internet access with your neighbors.  This could negatively impact your Internet speed.

29 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  DSL (digital subscriber line) uses telephone lines to carry digital signals.  Unlike your normal phone line that’s designed to carry analog signals (sound), DSL lines are designed to carry digital signals and thus are much faster than ordinary phone lines.  DSL averages speeds of 384 Kbps to 20Mbps, which is slower than cable – but generally less expensive.  The biggest problem with DSL is its distance limitations.  You must be within 3 miles of the DSL service provider’s facilities.

30 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Fiber-to-the-home (FTTH) is the fastest of the broadband alternatives, with top speeds of 300-500Mbps – but at a premium. Most companies offer rates only of up to 150 Mbps.  Fiber can cost two to three times as much as DSL or cable for the highest speeds.  It can carry Internet, TV, and phone calls to your home over fiber-optic cable and is available in limited areas.

31 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  In the United States, the primary FTTH service is Verizon FiOS (Fiber Optic Service).  Google fiber, which is currently available in limited markets, offers speeds of 1 Gbps.  Unlike cable and DSL lines, FTTH requires a contractor to lay a fiber-optic conduit directly to the home.

32 Internet Connection: Wired Dial-up Broadband Options CableDSLFTTH  Least expensive  Uses regular phone line  $10-$30 per month  Very slow, maxing out at 56 Kbps  Offered by cable TV providers  Cable speeds range from 1 Mbps – 50 Mbps  Uses phone line to carry digital signal  Average speeds of 384 Kbps – 7 Mbps  Fastest broadband alternative  Speeds top out at 300 Mbps  Can carry Internet, phone, and TV  Uses fiber optic cables  Limited areas of availability Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

33 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  There are several wireless alternatives available.  These options include:  Mobile Cellular Access  WiFi  Satellite

34 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Mobile Internet access allows you to connect to the Internet using the cellular network standards 3G (third generation) and 4G (fourth generation).  4G is faster and includes WiMAX Mobile Internet and LTE (Long Term Evolution) technologies.  The signals are transmitted by a series of cellular towers – thus – coverage isn’t universal.

35 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Coverage maps are available on the providers’ websites.  3G/4G can be used on personal computers with a special adapter.  Special modems make 4G available at home.  Top speeds are considered broadband and can potentially equal those associated with wired broadband service.

36 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Samsung Electronics and other companies are developing mobile technologies for fifth generation networks that will provide data transmission up to several hundred times faster than the current 4G technology.  The new 5G networks will transmit data up to 1 Gbps, which exceeds the wired broadband speeds currently available to most consumers.

37 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  The 5G networks will transmit large amounts of data over long distances, using a wide band of frequencies.  With such speeds, you will be able to download a full-length high-definition movie in seconds; video streaming will be seamless, with no lagging; and online games will be played in real time.  Samsung expects to implement 5G by 2020.

38 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Satellite Internet access is a more global and more expensive option.  Satellite service speeds are comparable to DSL.  You need a clear view of the southern sky, where the communications satellites are positioned.  Weather conditions can affect your service.  You would probably only consider satellite if there were no other option available.

39 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Municipal WiFi is offered in some cities and towns.  CBS Mobile Zone is available in central Manhattan.  Wireless Philadelphia currently covers most of the city for free.  WiFi hotspots are wireless access points that are available in many public locations (airports, schools, hotels, etc.).  WiFi is the same type of wireless technology you may have in your home.

40 Internet Connection: Wireless Wireless Options LTESatelliteMunicipal WiFi  4G service  Connects to the Internet via cellular networks  More global and more expensive option  Need a clear view of the southern sky  Weather conditions can affect service  Considered when other options are not available  Offered in some cities and towns  WiFi hotspots  Free  Fee-based  Available in many public locations Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

41 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Today, most cell phones offer at least a limited ability to connect to the Internet.  Smartphones, tablets, video game consoles, and even your media player may be able to connect via cellular or WiFi.  Some e-readers include free 3G Internet access to shop for and download books and to access other resources.  These devices generally have small screens and limited keyboards, which can make them more difficult.

42 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  However, they’re becoming more powerful and easier to use.  Many people rely on such devices as their primary Internet access device.  While only about 25% of the world’s population have personal computers, over 60% have cell phones.

43 Internet Connection Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Satellite phones connect to satellites instead of cellular towers, making them useful in places where cell service is lacking.  According to the Pew Research Center, in 2015, 85 percent of adults in the U.S. were Internet users and 70 % of adults has home broadband access.

44 Internet Connection Mobile Devices  Smartphones  Cell phones  PDAs  Video game consoles (Xbox, Wii, PS3)  Portable media players (iPod, iPad)  eBook readers (Kindle, Nook)  Satellite phones Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

45 ProviderService Type Speed Upstream/ Downstream CostExtrasOther Research two types of Internet access that are available where you live. Create a table like this one to compare features. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

46 Key Terms Objective : Overview 3 Surf’s Up 1.Define browsers and what they do 2.Compare the following browsers: Internet Explorer, Firefox, Chrome, Safari, and mobile browsers 3.Discuss ways to configure Web browsers  Add-on  Home page  HTML (Hypertext Markup Language) Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Mobile browser (microbrowser)  Plug-in  Web browser  Web page

47 Web Browsers Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  Most information on the Web is in the form of basic Web pages, which are written in HTML (hypertext markup language).  HTML is the authoring language that defines the structure of a web page.  Web browsers (Microsoft Internet Explorer, Mozilla Firefox, and Apple Safari) are programs that interpret HTML to display Web pages as you browse the Internet.

48  Although these are the most widely used browsers for PCs, there are actually many alternatives, including:  Chrome  Opera  Safari  Microsoft Edge  The first Web Browser, Mosaic, was released in 1993.  Mosaic eventually became Netscape Navigator, which dominated the market until Microsoft got in the game. Web Browsers

49 Browser Features Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall Menu Bookmarks Tabbed browsing Search bar Address bar Mozilla Firefox

50  INTERNET EXPLORER:  First released in 1995.  Internet Explorer (IE) has become the leading web browser.  IE is included with Windows, so there’s no special download needed.  As of this writing, IE11 is the current version.  IE holds a 43% market share of desktop browsers. Web Browsers

51  INTERNET EXPLORER:  Windows 8.1 includes two versions of IE.  A full screen app and a desktop version.  Windows 10 includes the desktop version of IE11, and a new browser – Microsoft Edge – which has replaced IE as the default browser. Web Browsers

52  INTERNET EXPLORER:  Some important features of Edge and Internet Explorer are:  Navigation buttons:  Provide a means to navigate back and forward through browsed Web pages.  Address Bar:  Contains the Web address of the current Web page.  You can also search the web from the address bar without having to go to a search provider’s website first.  Favorites:  Allows you to save Web addresses, giving you easy access to your favorite websites.  Bookmarks Web Browsers

53  INTERNET EXPLORER:  Some important features of Edge and Internet Explorer are:  Search box:  Allows you to search the Web from your current Web page without having to go to a search provider’s website first.  Tabbed Browsing:  Allows you to have multiple Web pages open in tabs.  Command Bar:  Contains easy access to most settings and features of IE. Web Browsers

54 Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall  The first version of Mozilla Firefox was released in 2004.  At the time, Internet Explorer had become the dominant Web browser and Netscape was at the end of its life.  As of April, 2014, Firefox had a market share of 12.5%.  Firefox is available for Windows, OS X, and Linux  Firefox is free and easy to install. However, it requires you to go out and download it.

55  CHROME:  Released in 2008.  As of April, 2014, Google Chrome had about a 31% desktop browser market share and about 14% of the mobile browser market.  It has a streamlined interface but is still very similar to Edge, IE and Firefox.  Chrome’s main focus is on speed, and it does load Web pages faster than other browsers.  But it’s not as full-featured as Firefox and IE. Web Browsers

56  SAFARI:  The most popular Web browser for Macs but has an overall market share of about 10%.  It comes bundled with MAC OS X and is also available for Windows.  One of the slickest features of Safari is the Top Sites preview of your 24 most visited websites.  Safari places stars in the corners of the thumbnails of the sites that have changed since the last time you viewed them. Web Browsers

57 Internet Explorer Mozilla Firefox Google Chrome Apple Safari  Released in 1995  Leading Web browser  Included with Windows OS  Released in 2004  Similar in look to IE  Free and easy to install  Released in 2008  Streamlined interface  Similar to IE and Firefox, but not as many features  Main focus is on speed  Most popular browser for Macs  Bundled with Mac OS X  Available for Windows Mobile Browsers Internet Explorer FirefoxOperaSafariProprietary Kindle, Blackberry, Android Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

58  Small screen devices, such as tablets, e- readers, and smartphones, use mobile browsers, which are sometimes called microbrowsers.  IE, Firefox, Safari, and Opera all come in mobile versions.  Other microbrowsers are proprietary:  Kindle  Android  Blackberry  Most websites can be accessed with a mobile browser, and many websites offer alternative pages that are optimized for a mobile browser. Web Browsers

59 Configuring Browsers  The first time you open any browser, it will have default settings (home page and search provider).  You should customize it for your own use.  The term home page has several meanings.  It can mean the first page of a website.  The web page that appears when you first open your browser. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

60  The default home page for IE is msn.com or bing.com.  You can set any page you want as your home page.  Because most browsers support tabbed browsing, you can actually set multiple home pages.  Microsoft Edge does not use a home page by default but rather a news feed you can customize. Configuring Browsers

61  When you type a search term in the address bar or search box of your browser, what search provider is used?  By default, the search provider will probably either be Microsoft Bing or Google.  The provider your computer manufacturer or ISP chose.  You can modify this to your own favorites.  In IE, click the arrow next to the magnifying glass in the address bar, and you’ll see what search providers are already set up.  You can choose any one of them.  If your favorite is missing, click Add.  This will take you to a web page with search providers you can choose. Configuring Browsers

62  Microsoft Edge defaults to Bing, but you can add other search engines from the settings menu, under Advanced settings.  Safari does not allow you to add search providers. Configuring Browsers

63  You can extend the functionality of your web browser by installing add-ons, plug-ins, extensions, and toolbars.  A plug-in is a third-party program, such as Adobe Reader.  An add-on is created for a specific browser to add features to it.  Firefox is the king of add-ons – there are hundreds of them available.  IE has a smaller number of add-ons. Configuring Browsers

64  Adding a toolbar to your browser gives you quick access to the features of the application that installed it.  Be wary of toolbars that come bundled with software you install.  Toolbars can be a source of malware and may slow down your browsing as well.  Plug-in software, such as Adobe Flash Player, Microsoft Silverlight, and Sun Java, helps your browser to display the multimedia- rich, interactive, dynamic content that’s increasingly common on the internet. Configuring Browsers

65  If you try to view a video on YouTube or play games on Facebook, you need Adobe Flash Player.  If your school uses a learning management system such as Blackboard, you’ll need to install Sun Java on your computer.  Installing plug-ins is quick and free.  To see which add-ons and plug-ins are installed on your computer in IE:  Open the Tools menu  Click Manage Add-ons.  In Firefox – Choose Add-ons from the menu Configuring Browsers

66  For many people, choosing a browser is largely a matter of using whatever is available or preinstalled on their device.  You do, however, have options if you’re not happy with that choice.  You can and should customize your browser to fit your needs.  Make it work for you and you’ll enjoy the experience even more. Configuring Browsers

67 Research the version and market shares of the top five Web browsers. How has this changed since this article was written? Are there any in the current list of five that were not mentioned in this book? Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

68 Key Terms Objective : Overview 4 Navigating the Net 1.Demonstrate how to navigate the Web 2.Understand the parts of a Web address 3.Learn how to create smart searches  Domain name  Domain Name System (DNS)  Home page  Internet Protocol (IP) address  Search engine  Top-level domain (TLD)  Uniform resource locator (URL)  Website Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

69 Ways to Navigate  There are two ways to navigate the Web.  First you can type in the URL (uniform resource locator) or Website address (http://www.google.com)  Or you can follow the hyperlinks in the Web pages from one place to the next.  A website consists of one or more Web pages that are all located in the same place. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

70 Ways to Navigate  The home page of a website is the main or starting page.  The page you see when you type in the Web address for a site. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

71 Parts of a URL http://www.google.com  http – The protocol that tells your computer what type of page you’re looking at.  http – A Web page;  https – A secure Web page;  ftp – File Transfer Protocol  It is so likely to be http that you can actually leave this part of the address out when you type it. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

72 Parts of a URL http://www.google.com .com – Known as the top-level domain (TLD) and represents the type of website you’re visiting.  Common TLDs are: .com –commercial .edu – educational .gov - government Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

73 Parts of a URL  Today, there are so many Websites that more TLDs are needed.  Websites outside the United States often have a country code TLD. .ca – Canada .af - Afganistan .uk – United Kingdom Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

74 Current Top-Level Domains. aero Members of the air transport industry.biz Businesses.com Can be used by anyone.coop Cooperative associations.edu Degree granting institutions.govUnited States government.info Information service providers.mil United States military.museum Museums.name Individuals.net Networking organizations.org Organizations (often nonprofits).pro Credentialed professionals

75 Parts of a URL http://www.google.com  The domain name – (google) precedes the TLD and is sometimes called the second-level domain.  The domain name represents a company or product name and makes it easy to remember the address. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

76 Parts of a URL http://www.google.com  The www represents the computer on the google domain and is called the third-level domain.  It is common to name the computer www, so this part of the URL is also often omitted. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

77 Parts of a URL Protocol Top-level Domain (TLD) Third-level Domain Domain Name or Second-level Domain http://www.google.com Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

78 The Web Address  SO, typing : http://www.google.com or merely google.com will result in the same thing.http://www.google.com  When you visit other pages on a website, the URL will have an additional part after the TLD. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

79 Parts of a URL  To view the page about the band Tom Petty and hear the Heartbreakers on Facebook, you can type facebook.com/TomPetty. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

80 Parts of a URL  Computers speak in numbers, so computers on the Internet are assigned IP (Internet protocol) addresses.  An IP address is a unique numeric address assigned to each node on a network.  ICANN (Internet Corporation for Assigned Names and Numbers) coordinates the Internet naming system. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

81 Parts of a URL  IP addresses are composed of numbers, which can be hard for a person to remember, so the DNS (Domain Name System) was developed.  The DNS System allows us to use a friendly name such as google.com instead of an IP address such as 74.125.224.72 to contact a website. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

82 Parts of a URL  When you enter a URL in your browser, your computer requests the IP address of the computer.  Your DNS server (provided by your ISP) locates the IP address information and sends it back to your computer, which then uses it to address your request. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

83 The Domain Name System  The User computer sends a request to the DNS server requesting the IP address of google.com.  The DNS server replies with the IP address “74.125.224.72”.  The User computer requests page from “74.125.224.72”.  The Web server at “74.125.224.72” delivers google.com home page. Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

84 Searching the Web A search engine is a database that indexes the Web. Keywords, advanced search tools, and Boolean operators can refine your search.

85 Search Engines  A set of programs that searches the Web for specific keywords you wish to query and then returns a list of Web sites on which those keywords are found

86 Search Engines  Have three parts  The first part is a program (spider) which constantly collects data on the Web.  Spiders get their names because they crawl over the Web using multiple “legs” to visit many sites simultaneously.  As the spider collects data, the second part of the search engine (indexer) organizes the data into a large database.  When you use a search engine, you interact with the third part – the search engine software  This software searches the indexed data, pulling out relevant information according to your search.  The resulting list appears in your Web browser as a list of hits or sites that match your search.

87 Search Engines  Each search engine uses a unique formula, or algorithm, to formulate the search and create the resulting index of related sites.  Most search engines rank their results based on the frequency of the appearance of your queried keywords in Web sites as well as the location of those words in the sites.

88 Popular Search Sites 88 AltaVistawww.altavista.comKeyword search engine Clustywww.clusty.com Keyword search engine that groups similar results into clusters ChaChawww.chacha.com Don’t like your search results? This site lets you chat with a real live professional guide who helps you search, and it’s free of charge. Complete-Planetwww.completeplanet.com Deep Web directory that searches databases not normally searched by typical search engines Dogpilewww.dogpile.com Metasearch engine that searches Google, Yahoo!, MSN Search, and Ask Excitewww.excite.comPortal with keyword search capabilities InfoMinewww.infomine.com Subject directory of academic resources with keyword search engine capabilities Rollyowww.rollyo.com Short for Roll Your Own Search Engine. Basically, this site lets you create your own search engine (searchroll) that searches just the sites you want it to search. Open Directory Project www.dmoz.orgSubject directory with keyword search capabilities Stumbleuponwww.stumbleupon.com Lets you rate pages thumbs up or thumbs down. As it learns your preferences, your search results improve. Technoratiwww.technorati.comA great search engine for blog content

89 Research various search engines. Select two that look interesting and search for the name of your favorite sports team. Did you get the same results? How were they different? Read the About section of the search tool to determine how content is added. You can usually find this link at the bottom of a Web page. What are some of the unique features of each? Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

90 Key Terms Objective : Overview 5 Would I Lie to You? 1.Discuss how to evaluate the credibility of information found on the Web 2.Define user-generated content 3.Discuss the importance of information literacy  User-generated content Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

91 Credibility and the Web  The Internet is full of user-generated content  Content written by everyday users  Blogs  Websites  Wikis  Social media sites  It is important to know  What is credible  How to evaluate the information you find Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

92 Evaluating Web Sites For research  When using the Internet for research, you shouldn’t assume that everything you find is accurate and appropriate to use.  Evaluating the content of a web site is important.  Before you believe what the site says or take action based on the information presented.

93 Evaluating Web Sites For research  Authority - Who is the author of the article or Web site sponsor?  Some sites include a page with information about the author or the site’s sponsor.  If the author is well known or the site is published by a reputable news source, you can feel more confident using it as a source.

94 Evaluating Web Sites For research  Audience - What audience is the site geared toward?  Ensure that the content, tone, and style of the site match your needs.  Bias - Is the site biased?  The purpose of many Web sites is to sell you a product or service, or to persuade rather than inform.  Look for sites that offer several sets of facts or consider opinions from several sources.

95 Evaluating Web Sites For research  Relevance - Is the information current?  Material can last a long time on the Web  Look for a date on information to make sure it is current  Links - Are links available and appropriate?  Check out the links provided on the site to determine whether they are still working and appropriate for your needs

96 Evaluating Web Sites For research  The answers to these questions will help you decide whether you should consider a Web site to be a good source of information.

97 Credibility and the Web Considerations:  When was the resource created or updated?  Is the information current enough for your topic?  Are there references given for the resource?  Is the content primarily opinion?  Who created the resource?  Is there evidence that the creator or organization is an expert on this subject?  Why was the resource put on the Web?  What is the domain extension?  Based on the writing style and vocabulary, who is the intended audience? Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

98 Compare these two websites based on the guidelines discussed in this article:  www.choosemyplate.gov www.choosemyplate.gov  www.foodpyramid.com www.foodpyramid.com Visualizing TechnologyCopyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

99 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Printed in the United States of America. Copyright © 2014 Pearson Education, Inc. Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall Copyright © 2014 Pearson Education, Inc. Publishing as Prentice HallVisualizing Technology


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