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E-learning Tools and Technologies X Web browsers X 105 6 Web browsers Netscape 6.2—Windows XP The page that worked fine in Netscape 4.7 appears garbled in Netscape 6.2. This version of Netscape does not support all the features previously supported in Netscape 4.7. Therefore, the dual coding used to ensure cross- browser compatibility does not work in this case. To make this page display correctly in Netscape 6.2 would require additional JavaScript programming. Internet Explorer 6.0.2—Windows XP The FAQ page displays as intended in Internet Explorer 6.0.2 on Windows XP. The dynamic HTML effects used to show and hide answers work as designed. Wiley Publishing, Inc. 106 W Web browsers W E-learning Tools and Technologies Netscape 4.7—Macintosh, OS 9.2 The original FAQ page displays fine in Netscape 4.7 for the Macintosh. The JavaScript correctly identifies the version. The expanding list works. Internet Explorer 5.5—Macintosh, OS 9.2 The same FAQ page displays OK in Internet Explorer 5.5 for the Macintosh, but the line under the page title is thicker than intended. The expanding list works. Wiley Publishing, Inc. E-learning Tools and Technologies X Web browsers X 107 6 Web browsers Internet Explorer 5.5—Macintosh, OS X The FAQ page displays nicely in Internet Explorer 5.5 for the Macintosh. The expanding list works. Netscape 6.2—Macintosh, OS X The FAQ page appears garbled in Netscape 6.2 for the Macintosh. The dual coding used to ensure cross- browser compatibility does not work in this case. To make this page display correctly would require additional JavaScript programming to accommodate Netscape 6 and higher browsers. The moral of this demonstration is that browsers are pretty much the same, but differences—even between subsequent versions of a single brand—can make a hash of your careful designs. Making Web content “cross-browser” is often harder than most people think. And these examples are just from two brands. Wiley Publishing, Inc. 108 W Web browsers W E-learning Tools and Technologies POPULAR WEB BROWSERS In the world of e-learning, the two big names in browsers are Netscape’s Navigator and Microsoft’s Internet Explorer. Together they account for the vast majority of corporate, educational, and home browsers. In addition to these giants, there are other specialty browsers and variants that are of interest to those designing and offering e-learning. Let’s tour the showroom. Internet Explorer microsoft.com Internet Explorer (IE for short) is very popular in businesses, especially ones that have standardized on Windows operating systems and/or Microsoft Office products. As of September 2002, all versions of Internet Explorer make up 88% to 90% of the browser usage on personal computers and workstations, according to thecounter.com. IE is currently available for the Macintosh operating system as well as for Windows. One of the pleasant side effects of Internet Explorer being tightly coupled with the Windows operating system is that it starts almost instantaneously. Internet Explorer is also well integrated with Microsoft’s Office suite. If you link to Office documents like Excel spreadsheets or Word documents from within your e-learning, learners will be able to view these documents within the browser window—as long as the appropriate Office application is installed on their computer. This capability eliminates the need to open a new window and separately start up an Office application. Page displayed in Internet Explorer 6 Wiley Publishing, Inc. E-learning Tools and Technologies X Web browsers X 109 6 Web browsers Moving into the geeky realm, IE supports Level 1 Cascading Style Sheets (CSS), Level 1 Document Object Model (DOM), Vector Markup Language (VML), and the proposed Synchronized Multimedia Integration Language (SMIL) 2.0 standards. It also supports client-side VBScript scripting in addition to JavaScript. Client-side scripts are little programs and routines that are included right in the HTML page and run in the browser. Internet Explorer can also display XML (Extensible Markup Language) files that reference either XSL (Extensible Stylesheet Language) style sheet or Cascading Style Sheets. This ability to parse and display XML files offloads work from the server to the learner’s browser. That is, the server doesn’t have to transform the XML file and the XSL style sheet into an HTML page each time the XML file is requested, the learner’s browser does the work. For businesses, Internet service providers, and other organization that may want a customized version of Internet Explorer, Microsoft provides an Internet Explorer Administration Kit that can be used to create a custom-configured installation package. Netscape Navigator netscape.com Netscape was the first full-featured browser to make its way into homes, campuses, and businesses. It established the expectation that Web content could be displayed consistently from platform to platform. In fact, in 1995 Netscape had a market share of over 80%. Netscape garnered its early popularity by adding its own extensions to the standard HTML tags supported by the World Wide Web consortium. The capabilities that resulted from these extensions were often flashier than what other browsers could produce. To attract Netscape users, Internet Explorer added its own special extensions to match and exceed Netscape’s capabilities. As a result, Web sites that took This talk of DOMs, CSSs, and the like may seem like more detail than you need. However, as you design your e-learning, these capabilities will influence what features you can provide and how you will need to implement them. Page displayed in Netscape Navigator 6.2 Wiley Publishing, Inc. 110 W Web browsers W E-learning Tools and Technologies advantage of a browser’s special features were not easily displayed by the other browser without special scripting being added to the HTML pages. These incompatibilities still exist. Today, Netscape is still found on home computers, on university campuses, and on operating systems other than Windows. According to thecounter.com, all versions of Netscape account for 10% of browser usage. The current version (7) is available for Macintosh, Linux, and Windows operating systems. If you need to support a variety of UNIX platforms, you will need to use either version 4.8 of Netscape Communicator or version 4.79 of Netscape Navigator. Netscape supports CSS as well as Level 1 DOM and client-side JavaScript. Netscape can also display XML files with referenced CSS files—but not XML files that reference an XSL style sheet. There is a customization kit available that allows you to create a customized version of the Netscape browser. For instance you can add your logo and special bookmarks, eliminate features, pre-configure connection information, and build a special installation package. Other browsers of interest Almost all e-learning is designed for Netscape or IE browsers. So why consider other browsers? Because they are there? Or, because they may represent niche markets or be important in testing emerging standards or meeting accessibility regulations. Here are some other browsers you may need to be aware of as you plan your e-learning project. Mozilla mozilla.org Mozilla is an open-source browser available for Windows, Macintosh, Linux, and some versions of UNIX. According to the Mozilla Organization, this browser is designed for standards compliance, performance, and portability from platform to platform. Mozilla is named for the original code- name of the product that came to be known as Netscape Navigator. Since 1998, Page displayed in Mozilla Wiley Publishing, Inc. E-learning Tools and Technologies X Web browsers X 111 6 Web browsers Netscape has built its browser on incremental releases of the Mozilla browser. However, the first public release of Mozilla 1.0 did not occur until June 5, 2002. Along with the browser, the Mozilla installation also includes a news and mail reader, an Internet Relay Chat (IRC) client, and a minimal HTML editor. All in all, it is very similar in basic functionality to Netscape 6.2. Since it is available as open-source, Mozilla can be customized, for example, to produce an ideal browser for your e-learning. Amaya w3c.org/Amaya Amaya is the World Wide Web Consortium’s test-bed browser. According to the W3C, Amaya was “specifically conceived to serve as a … client to experiment and demonstrate new Web protocols and formats as well as new extensions to existing ones.” Its features are limited. For instance, it does not support pop-up windows or frames. And its support for Cascading Style Sheets is still somewhat limited. Amaya is unsuitable for general e-learning activities, especially if learners will be accessing third-party e-learning providers. Amaya does not support the level of interactivity needed for rich content. However, its support for the W3C Web Accessibility Initiative and specialized data formats, such as Math Markup Language (MathML) and Scaleable Vector Graphics (SVG), may carve out some niches for Amaya. Page displayed in Amaya. Notice the misaligned columns. Wiley Publishing, Inc. 112 W Web browsers W E-learning Tools and Technologies AOL aol.com AOL (America Online), the world’s largest ISP, provides its users with a customized version of the Internet Explorer browser, which is surprising since AOL and Netscape are divisions of AOL Time Warner. However, there is a version of Netscape being tested that will probably be the default browser in upcoming versions of AOL. Page displayed in AOL, version 7. The page is well- formed, but notice the extra width due to the AOL-specific controls. If you suspect your learners will be connecting to your e-learning using AOL, carefully test your content with the AOL browser—especially in situations where learners must log into a secure system. If there are difficulties, you may want to give your learners instructions on how to start either Netscape or Internet Explorer once they have connected to the Internet using AOL. Wiley Publishing, Inc. E-learning Tools and Technologies X Web browsers X 113 6 Web browsers Opera opera.com The Opera browser prides itself on being small, fast, and standards-compliant. It is also noted for its ability to interface with accessibility aids for the visually impaired. Opera is available for a large variety of operating systems, as well as embedded systems like that found on the Nokia 9210i/9290 Communicator. The most difficult issue developers will encounter will be in the ways Opera’s Document Object Model differs from either IE or Netscape—especially when using dynamic layers. If your content is just static pages, these differences should pose no problems for you. Lynx lynx.browser.org Page displayed in Lynx Lynx is a well-established text-only browser used by people who do not need to see graphics or who do not want to wait for them to download and form. Lynx does not support frames, tables, or any visual media. It is included in this list for completeness; however, it is not an adequate platform for rich, interactive e-learning. Lynx may be helpful in debugging pages that thwart screen readers for the blind. Page displayed in Opera Wiley Publishing, Inc. 114 W Web browsers W E-learning Tools and Technologies MSN TV MSN TV is designed to let users navigate the Web and display pages on their television screens. We’re not talking about high-definition television (HDTV) here. Oh no, we mean plain, ordinary, fuzzy TV that makes the screen of that antiquated computer in your basement seem as crisp and vast as the screen at your local Cineplex. Page displayed in the WebTV testing browser for MSN TV The MSN TV browser is limited to basic HTML with some JavaScript and Cascading Style Sheet features. Furthermore, MSN TV does not scroll pages horizontally, but squeezes the page to fit the available width. Most standard Web fonts are not supported. If you suspect your learners are likely to use some kind of television browser to access your e-learning, think about providing an alternative version of your learning material optimized for the limitations of the television screen. Wiley Publishing, Inc. [...]... Internet Explorer 5 or later will see the Office documents within their browser window Those with Netscape and Opera will see the content in a separate window Wiley Publishing, Inc Media players and viewers Viewed in the Adobe Acrobat Reader window 7 136 Media players and viewers E- learning Tools and Technologies A Microsoft Excel spreadsheet displayed directly in Internet Explorer Microsoft’s Internet... Just be sure to test courses with the targeted browsers to spot programming errors or unexpected results Document Object Model The Document Object Model describes the structure of a Web page, such as the elements or tags on a page, the number of elements, the order of the elements, the properties of these elements, and finally, how each element or tag looks when it is displayed For instance, a DOM lets... test on Opera We don’t need no stinkin’ server Browsers can view Web content residing on a CD-ROM, a local computer, a network computer, and a Web server As long as the Web content does not require processing by a Web server, it can be located anywhere the learner can browse and open files (Server processing might be necessary to capture data entered on a form or to record test results in a remote... means that developers should not be lulled into complacency because their pages look fine in Internet Explorer They should validate their HTML to ensure their code is well-formed (all closing tags are present and no tags are incorrectly nested) E- learning Tools and Technologies Web browsers 117 coder omits a DOCTYPE definition or uses LANGUAGE instead of TYPE to indicate the scripting language used... In deliberating the capabilities of Web browsers, keep in mind that browsers need not display all the content of your e- learning Some content may be displayed by media players and viewers, which are the subject of the next chapter Wiley Publishing, Inc 7 Media players and viewers When we talked about browsers in chapter 6, we made a distinction between content that the browser can view natively and. .. place those pages into a separate directory within the Web site and use the NT internal security scheme to control access That is, each potential user of the protected pages is a documented user of the server, or a member of a particular group When a user tries to access one of those protected Web pages, a dialog box asks for their user name and password If the user is accessing the page with Internet... the full Web address of hypertext links within a page Visual cues to indicate whether a Web site is on a secure server—especially important when data is being obtained from a learner Wiley Publishing, Inc E- learning Tools and Technologies Web browsers 119 Security To what extent does a browser facilitate secure transactions for e- commerce and confidential material? Ideally, the browser you choose... directly by the browser Some media players handle simple, linear media such as sound, music, and video A second 129 Wiley Publishing, Inc  130 Media players and viewers E- learning Tools and Technologies class of media players, sometimes called viewers, displays proprietary file formats These formats tend to be more complex and may mix media and involve rich interactivity Although general media players can... specific type If the Content-Type is text/html, the browser displays the data itself If the Content-Type is video/mpeg, or any other type the browser cannot display, it consults its MIME table to learn what media player to use Wiley Publishing, Inc E- learning Tools and Technologies Media players and viewers 131 Here is an example of a Web page with embedded video along with the HTTP header information... called viewers or readers Because viewers are so closely allied with the format they are designed to display, your choice of viewer is imposed by the design decisions you make for your e- learning product If you decide to develop content in Macromedia Flash, then you need to ensure learners have the Flash Player installed on their computer Likewise, if you plan to convert documents to Adobe PDF file format, . the server doesn’t have to transform the XML file and the XSL style sheet into an HTML page each time the XML file is requested, the learner’s browser does the work. For businesses, Internet. browsers? Because they are there? Or, because they may represent niche markets or be important in testing emerging standards or meeting accessibility regulations. Here are some other browsers. reference either XSL (Extensible Stylesheet Language) style sheet or Cascading Style Sheets. This ability to parse and display XML files offloads work from the server to the learner’s browser.