CHAPTER 1
An Introduction to the WebTOC

" What is a Web
said she ", she said
I could not reply
I knew not how she fed

          B. Confused

The features of the World-Wide Web that distinguish it from the internet are:

* ease of access to information

* screen ready graphics

* standardized text formatting for consistent display

* ability for the infopage designer to control display

The World-Wide Web is a very powerful and convenient way to communicate using information transfer protocols, i.e. step by step procedures that check the the text being transferred from one point to another. The more reliable a computer transfer is, the less chance there is that the information will arrive damaged and consequently unusable. Remember that there is a lot more information in a computer file than just letters. If the file set-up information is damaged, the computer will not know where to begin reading the textual part of the file. The result of errors in file transfer is a garbled and unusable string of computer digits. The internet transfer protocols are a way of checking each piece of data and correcting errors. A simple example is given by the following. Suppose I type a letter to you with the following line.

To see just how complicated the internet is, consider trying to set up a system of string and can telephones between you and all your friends. If you have seven friends each person would need six cans and you would need 28 strings to complete the network. In other words eight people with seven lines each with each pair of people sharing one line.

At the same time, the high energy physics community in North America and Europe realized that their relatively small community needed to be in constant contact in order to share ideas and results. This was necessary because of the high cost of experimentation. If new knowledge was slow in publication, it could mean many wasted hours and valuable resources squandered.

There was a need to establish data transfer protocols which would be consistent throughout the world and available on machines at each important site within the network. Other problems occurred as well. Information can not be simply passed from one point to another. The process is more like a rumor that passes from one person to the next until it reaches you. If there is no way to check the integrity of the information, it is very likely the the rumor will run wild. Special documentation must be attached to every piece of information passing through the internet. The process goes something like this:

• You dial a long distance number from Omaha to Chicago on your telephone.
  
  
• The information goes to the switching department at your local phone company.
  
  
• The phone company looks for a direct open line to Chicago but none are available.
  
  
• The phone company finds an open line to Normal, Illinois.
  
  
• The phone company sends your call request (along with number information) to the phone switching department at Normal, Illinois.
  
  
• The phone company switching department in Normal, Illinois responds and accepts the transfer of duties.
  
  
• The process continues until a complete set of phone links are established between Omaha and Chicago.
  
  
• Finally, the phone company reclaims all the phone links when you hang up the phone.
  
  
  

Special protocol information must be attached to the information you request over the internet to ensure that it will eventually reach the right address. Unlike the telephone, each request is passed quickly and the connection is then broken until another request is made. Most of the information from a webpage is stored on your personal computer and is then made available by the browser. When you click on an object in the webpage, the information is readily accessible. This means that there are several computers within the network which do the work of storing and transmitting your requests and it happens all in the twinkling of an eye.

The early internet allowed for several kinds of information transfers. Some of the most popular features were:

• electronic mail
  
  
• news and bulletin boards
  
  
• talk (direct keyboard interaction between internet users)
  
  
• ASCII(text) and binary file transfer

While much of the original purpose of these features was to increase the flow of reliable information, some inhabitants of the internet were dissatisfied, both with the quality of information available and with the tedious procedures required to obtain even simple information.

The information system now know as the World-Wide Web will touch the lives of all of our students in one way or another. Using Multi-tasking computers and small notebook-like monitors could mean the beginning of a new era of the electronic classroom.

Technology is changing rapidly and it is difficult to envision what the future holds in store. It was not very long ago that the idea of personal computers seemed unlikely. The World-Wide Web was created only very recently and yet its growth has been astounding. Technology is changing so fast that cutting edge educational materials are soon out of date.

I began using a Computer Algebra System in about 1989 over a modem connected to a computer nearly 150 miles away. We had no great expectations and we were happy to be able to solve simple mathematical problems during class. Often times the modem connection failed. Often times hours of preparation resulted in a few minutes of classroom demonstrations and since the classroom computer was invariably different from my own, the demonstrations often failed. The use of the computer in the classroom was fraught with difficulties. Every two or three years the software would change or the software systems supported by the university would be dropped. We would scramble once again to catch up with the technology. I would sometimes complain that if the computer technology would just stop changing we could learn to use it in time to apply it in our classrooms.

The simple structure of the World-Wide Web along with its portability makes it a candidate to revolutionize computer science and its application to everyday life.

One of the unique features of the World-Wide Web is the open nature of information transfer. By an open system I mean that the system allows the weblian to easily access any participating server in the entire world. Each server, in turn, may contain a vast system of webpages with valuable information. The world of information suddenly opens up before student and teacher alike. Is it a yawning chasm, or a creative new World-Wide-one-room schoolhouse? It is both and this is the paradox. The World-Wide Web has grown at a rate that must seem unbelievable to its original developers, and with this uncontrolled growth there have emerged some problems.

We should not be surprised by this. Still, in other quarters the road ahead is filled with the expectation of an educational renaissance. Do not expect the commercial software manufactures to show any leadership in this direction. The good news is that there are many people in education that are giving freely of their time and talent to make the World-Wide Web a freeway to a better future in education. One has only to spend a short time browsing some of the educational lists on the search engines to see that the educational aspect of the Web is growing as fast as anything.

Here are some possible scenarios for the development of the World-Wide Web which we will discuss presently:

• The creation of an open educational Web-subsystem. I call this the Kindernet concept.
  
  
• Better filtering systems for protecting students from undesirable or false information.
  
  
• Greater organization of information and indexing schemes.

I assign several written papers in my History of Mathematics class each semester. I suggested that the World-wide Web might be helpful in finding material for their papers. One student actually used the infopages of an individual as references, something I frown upon. The infopages were not reviewed by any competent source and the information was filled with errors. The author of these pages claimed that " spiritual numerology " was respected in scientific circles. As a teacher, it is difficult to overestimate the educational damage that is done by false information appearing in print form. The example I have cited above is perhaps tame when one considers the effects of truly malicious writing on young accepting minds.

The solution of this problem is beyond the scope of this book. The best advice is to use professional sites that index related sites or use clickable maps for organizing available information. For example see the following sites for information on HTML:

• http://www.sandia.gov/sci_compute/html_ref.html
  
  
• http://www.cc.ukans.edu/info/HTML_quick.html
  
  
• "http://www.ncsa.uiuc.edu/General/Internet/WWW/HTMLPrimer.html
  
  
• http://www.wc3.org/hypertext/WWW/MarkUp/MarkUp.html
  
  

Once again, most of the real work in designing the hyperlink system on webpages has been done by the computer scientists that create browsers. As you know, using the hypertext transfer protocol, or http, usually requires a computer mouse (though systems can be designed which use only a keyboard). The system works something like this: The screen is divided into tiny regions. Let us say that one screen pixel represents such a region. As you move the mouse one way or another the computer is obtaining input information from the mouse. The computer processes this information and draws a pointer, or some other visual aid, on the screen in a position dictated by the mouse's movement. The window-system of your computer creates a table with the positions of clickable points. Usually, the system gives you a visual clue to indicate clickable regions. These clues become so familiar that you may find it difficult to recall what the visual clue is, without looking on your computer screen. In the case of hypertext, the browser typically gives us a visual clue for clickable anchor-regions by underlining text-anchors and outlining images but also by changing the pointer symbol on clickable regions. When the mouse is moved so that the pointer passes into a clickable region and the button on the mouse is then used, the computer executes a short program that tells the browser to fetch the file at the URL address defined by the anchor/hyperlink on the webpage.

The manner in which information is displayed using the hyperlink, differs conceptually from book style. A book is written in a page ordered style. The hyperlink concept gives the author the flexibility to allow the reader to quickly reference a topic, or explore a whole new world, simply with the click of a button.

If you have used a computer for some length of time, you have probably noticed that most help documents, in window-style environments, use the hyperlink document style. This was perhaps the first obvious practical use of this style. The World-Wide Web is built on a similar hyperlink document style system.

The typical window-help-system uses the hypertext link concept. The system is designed as a set of pages but they are not usually ordered. Rather, the pages are something like a dictionary, with alphabetically listed topics and a search capability. The reader may begin with one topic and immediately " click on " another topic while setting bookmarks for ease of reference and keeping a history. If a word in the referenced help document was underlined then it became a clickable path to the next topic of interest. If this topic did not prove to be of help, the reader could backup or return to the previous page.

As you can see, most of the basic functions used by Web browsers were already in place when the concept of the Web was born. Using the existing window-help-systems meant that to build a Web browser one simply had to adapt the window-help-system to the internet protocols. On the World-Wide Web, each webpage may be connected to a whole series of other webpages. It is precisely these reference points that we call anchors, or hyperlinks. The typical window-help-system is an example of a closed orbit web-system, in contrast to the World-Wide Web which is an open orbit web-system.

The internet experiences of our students vary a great deal. Some are websperts (i. e. experts) others are weblians (i.e. knowledgable) and still others are weblings (i.e. fledgling weblians) and finally others who have no experience on the Web at all. Some students are adept at the keyboard, others work more slowly.

The series of projects in this book are aimed at the 4th to 8th grade level student and are designed to be rewarding for all kinds of students. Those with more knowledge and experience should be encouraged to share their knowledge to help others.

At this point in time it is not an easy matter for students to browse the Web. The child, the teacher, and the parent should all be aware that the Web is not entirely unlike the old lawless west of folklore imagination. Caution and care should be exercised, but if a few precautions are observed, then browsing the Web can be educational and fun.

Information on the World-Wide Web is not generally of the same reliability as information in books. The information found in books has usually been reviewed by the peers of the author as well as experts and editors. There is currently no general guarantee that general websites have had the same sort of scrutiny. Again, with a few precautions you can be certain that the information is reliable. The questions to ask are:

• Is the information obtained from a well known scientific or cultural organization. A good example is NASA, but there are countless others.
  
  
• Is the information obtained from a well known professional organization. Two such example are the NEA and the AMA. Once again you can probably think of many other examples
  
  
• Is the information obtained from a reliable commercial site? Be aware that almost all commercial sites have homepages intended as advertisements. Students should be cautious when clicking on icons that are clearly in the nature of advertising. This being said, it is also true that many commercial sites are interested in improving education. It is after all in their long term interest. Some newspapers maintain commercial websites. Compliment a commercial site using the e-mail webmaster features, when they deserve it. Some examples are:
  
  
  • http://www.apple.com/
    
    
  • http://www.nytimes.com



    (you must register and ignore advertising and this may sometime become a pay-for service)
    
    

  • http://www.pixar.com/"
    
    
• If the information is obtained from an organization or educational website consider the following questions:
  
  
  • Is this an official infopage of the website or a personal page?
    
    
  • Is the author of the page well known and professionally connected to the site? For example, see the director of the World-Wide Web consortium and founder of the concept of the web at
    
    
  • http://www.w3.org/pub/WWW/People/Berners-Lee/
    
    and find out about the history of the World-Wide Web.
    
    
  • What is the purpose of the webpage?
    
    

One of the revolutionary features of the Web is, surely, the ability to interact with the HTML documents. In addition, it is often possible to download educational computer software. In some cases, if your browser is Java aware (that is: if it can download and run javascripts and applets), then it will download interactive computer programs which will automatically run on your machine. For an example of interactive geometry, use the URL address:


http://aleph0.clarku.edu/~djoyce/java/elements/elements.html

and go to the geometric figure under the heading:

A Few Minutes Later

• Set up a classroom anchorpage with anchor-hyperlinks which determine the universe of acceptable infopages.
  
  
• Set a list of bookmarks to educational sites and require that the students stay within the orbits at the given site.
  
  
• Limit the type of sites student can browse.
  • Most government sites are safe. They look like:
    
            http://www.*.gov/
    
    where the asterisk represents a wildcard .
  • A great number of educational sites are safe especially if they are government related. The endings look like
    
            http://www.*.edu/
    
    While these site are generally safe they may be inadvertantly linked to unacceptable sites. Make it a rule that that once the student is at an education site that they remain or use only other educational links. This can be done by teaching the students to " look " before they click. In other words, have the students learn to read the URL address of the site in the hyperlink-view bar.
    
    
  • Many organizations sponsor educational homepages but they should be thoroughly previewed before they are added to your list of acceptable sites. The endings look like
    
            http://www.*.org/
    
    
  • Commercial sites should be used only if the site has been completely previewed. Even some excellent commercial site may have links to inappropriate pages. There are some sites which are likely to be safe, for instance
    
    
    • http://www.att.com/
    
    
    is the homepage of AT & T.
    
    
  • Try to avoid any site which is a personal homepage unattached to government or university sites, unless the author is well known and reputable.
    
    
  • Beware of websites that use the technique of frames to keep the student at the site while allowing the student to use hyperlinks to other sites. The hyperlinks appear inside the frame but the control remains at the initial site. It can be difficult to exit such sites. The individual designing such a site has most likely done this for a reason. One possible reason might be to allow the student to have a table of contents to several sites, but the designer should also allow the student to exit to another site.
    
    
  • Do not let the students give out e-mail addresses on forms or in e-mail unless you know the individuals or companies involved. It is easy to obtain a commercial website and use it as a company address.
    
    
  • Leave the warning boxes enabled and avoid websites which gather information on people who view the site