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Part
INTERNET SERIES
Class Manual
2
Exploring the
orl
W d WideW eb
WEB BROWSERS AND WEB SURFING
INTERNET SERIES
Class Manual
Prerequisites for Part Two, Exploring The World Wide Web, include completion Learn iT!’s Internet Part 1
course and basic Windows 95 skills..
This class introduces students to the functions of Web Browsers, concepts of the World Wide Web and
hypertext documents, web searching techniques, and Web site navigation.
After completing this course, students should have a good understanding of how to use the Netscape
Navigator software application to access Web pages, find information on the Internet, and use some of the
specific functions of Netscape to enhance their Internet experience.
9/1/98
Learn iT! Incorporated
250 Montgomery Street
San Francisco, California 94104
Phone 415.693.0250 • Fax 415.693.0286
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Introduction
Overview
The World Wide Web is a portion of the Internet that makes information easily accessible
through a point-and-click interface, and Web browsers are the software programs that
unlock the Web on any personal computer desktop. This class explores what the World
Wide Web is and the vast amount of information it contains. We will also learn how to use
Web browsers to visit and interact with Web sites and show you ways to take full advantage
of the powerful tools available for searching the World Wide Web.
Objectives
In this course you will learn:
• How Web pages have been linked to create the World Wide Web.
• How to Use Web browsers to explore the Web.
• How to Navigate through Web pages using the history list.
• Creating and Editing Bookmarks for your favorite sites.
• Searching the Web with Search Directories and Engines.
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What is the World Wide Web?
The World Wide Web is not really a physical place you could visit. Instead, the term World
Wide Web is used to identify the area of the Internet where connected documents called
Web pages find their home. What makes Web pages different from any other type of
document is that they contain clickable areas called hyperlinks, which allow users to transfer a
new Web page to their computer with a single click.
History
The idea of hypertext documents can be followed back to as early as 1965. But it was a
researcher at the European particle physics laboratory CERN in 1980 that really began the
ball rolling for the development of the global network of hypertext documents we know
today as the World Wide Web.
The researcher‘s name was Tim Berners-Lee and in 1980 wrote a notebook-style computer
program he called "Enquire-Within-Upon-Everything", which allowed links to be made
between arbitrary nodes in documents. Each node had a title, a type, and a list of bi-
directional links. "ENQUIRE," as it became known, would help CERN scientists share and
organize data more easily.
In March of 1989, Berners-Lee circulated a paper called "Information Management: A
Proposal" to propose a global ENQUIRE-style hypertext system that might manage
information on the burgeoning Internet. In May of 1990 the proposal is revised and the
name “World Wide Web” is added.
The WWW was created under the pretense that many people would be able to work
collaboratively by putting information on a web of hypertext documents. The WWW would
consist of servers that stored hypertext documents and client software programs, called
browsers, which would access the information on servers. Browsers would call up
information by searching for a file's Uniform Resource Locator (URL), or address, on the
Internet.
The Web Today
Today’s World Wide Web is most notable for the point-and-click interface (Graphic User
Interface) that makes navigation of information sites around the world as easy as navigating
around your computers desktop.
In 1993, the National Center for Supercomputing Applications funded a project for a
University of Wisconson student named Mark Andreessen. He designed a browser with the
GUI (Graphic User Interface) and called it the NCSA Mosaic. Andreessen later went on to
start a his own company know as Netscape Communication that sold the first consumer
Web browser programs for profit. Mosaic and Netscape’s “Navigator” software spawned
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enormous activity on the World Wide Web, attracting designers, programmers and -- most
importantly -- users to the WWW with their easy-to-use interfaces.
Web Browsers
A Web browser is a software program that retrieves
documents off the World Wide Web and then displays
them on a user's computer in an interactive
environment. All web browsers read documents off
the Internet that have been written in a special
language called Hypertext Markup Language (HTML).
For Web-surfers, hypertext is the most important word
of that name because it refers to the clickable
hyperlinks (or, more simply, "links") that allow anyone
to jump from one site to another on the WWW.
Why Browse?
When you access files on the World Wide Web you
are actually downloading copies of those files to your
computer, storing them onto your hard drive and then viewing them locally. The process of
viewing a local copy of a Web page is called browsing. This allows one Web site to have many
visitors at one time (sometimes thousands) and it minimizes the work that a Web server has
to do. And because your computer makes a copy of the Web page you are reading you do
not have to “exit” a Web site, just click a link or enter a new address to move on to a new
document.
What is a Cache?
Since Web browsers are constantly storing data to your computer’s hard drive, they must
delete that data automatically from time to time or your hard drive would fill up. All Web
browsers deal with this problem by using something called a “cache” to store Web page files
temporarily
A cache (pronounced "cash") temporarily stores information from web pages you've visited.
This includes text, graphics, audio, video and any other files embedded in a web page. If you
later revisit a page that is stored in the cache, browsers can retrieve the page from the cache
more quickly than retrieving the page again from its location out on the Internet.
The cache is also normally set to a certain size limit (typically 1 to 5 Megabytes) so it won’t
monopolize your entire hard drive with Web files. As the cache fills up to its limit, older files
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are erased to make room for new ones. This keeps recent documents close at hand while still
allowing you to browse to new pages.
Netscape vs. Microsoft
In this class we will be using Netscape Navigator, currently the world's most popular Web
browser. The close-running second place browser is Microsoft's Internet Explorer. These
two browsers are currently at the forefront of browser technology and are decidedly superior
to older browsers since they support many recent innovations in Web page design and
programming.
Since Netscape Navigator and Microsoft’s Internet Explorer are both Web browsers, they
must essentially do the same things as software programs. Many in the media and computer
industry have spoken of a “browser war” between the two companies in recent months. But
beneath the surface, there are really few differences in what the programs do. Each
company’s browser is designed to connect to hypertext servers on the Internet and retrieve
HTML documents. Even the look and feel of each browser is similar. So most of the tasks
you will learn will learn about using a Web browser today in Netscape will also apply if you
choose to use Internet Explorer instead
Using Netscape
We’ll now use the Netscape Web Browser to take a look at how Web browsers work. On the
following page is a picture of a typical Netscape program window.
Secure Site
when locked
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You have already seen the Netscape program window (above) in class one, but you may
want to use this graphic for reference since the rest of your work in class today will be
exploring this software program. Some of the elements of Netscape should be familiar from
other Windows programs. Like other programs, Netscape has a File menu for opening and
saving documents. This allows you to save web pages and then read them later when you are
off-line. But Netscape also has specialized tools to help you navigate the WWW. Next, you
will take a tour of these specialized tools in Netscape.
Netscape Buttons
Like most Windows programs, there are a series of shortcut buttons for you to use. These
buttons make use of the most popular and most used functions of Netscape. Here’s a
description of those functions and buttons:
The Back button. This button will take you to the previous, or last, Web Page you have
visited. You can go back and back, all the way back to the page you started at.
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The Forward button. After we have gone back with the back button, the forward button
will allow us to move forward. The forward button takes us in the opposite direction of the
back button.
The Reload button. The reload button will go to the location where the Web page we are
viewing is stored and reload it. In doing so, any changes, or updates, to the page that have
been made since we last received it will be displayed. Think of this as an update button.
The Home button. Clicking this button will take us to the page that is set up as our default
or ‘Home’ page in the Netscape program. By default, the home button will take us to
Netscape’s Home Page.
The Search button. This takes you to Netscape’s page with links the most popular search
engines.
The Guide button. This button takes you to Netscape’s home page with hyperlinks to
various categories similar to Yahoo.
The Print button. If you want to print the contents of the Web Page you are currently
viewing, press this button.
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The Security button. This gives you information about the page you’ve loaded and other
security information on encryption types.
The Stop button. Once you try to access a Web Page, you will notice that both the stop
button turns red and comets start ‘flying by’ in the background of the Netscape logo on the
far right of your screen. This is telling us that Netscape is trying to retrieve the information
you have requested. If you would like to stop this transfer, click on the ‘stop’ button. You
can also stop the page from loading by using your Esc (escape) key on your keyboard
Using the Go Menu / History
After you have been surfing the Web for a while you may wish to back up over large
amounts of documents. Thankfully, you do not have to hit your “back” button twenty times
if you need to jump back that far. Netscape keeps a record of the locations you have recently
visited in two places inside the program. The first is the “Go” menu, located in the menu bar
between “View” and “Communicator.” The Go menu allows you to quickly view the titles
of the Web pages you have seen recently and return to one by clicking on the name. This
view of the history is per session only.
The History feature (found inside the Communicator menu) will also allow you to see the
pages your browser has visited in the current session in a scrollable window, but it goes into
more depth. The History window will also show you the URL’s of the sites you have visited,
but not just for the session. It will show you the all the sites you have vistited, and allow you
to create bookmarks for those pages.
Now, lets take a tour of some web sites. This will build up our history list, then we can take
a look at it.
www.cnn.com- Cnn news
www.wunderground.com- Weather online
www.amazon.com- Amazon book store
www.fbi.org- Federal Bureau of Investigations
www.100hot.com- The 100 hottest sites
www.nytimes.com- NY Times online
www.pbs.org- Public Broadcasting
www.sfbg.com- San Francisco Bay Guardian
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lcweb.loc.gov- Library of Congress
www.sfgate.com- SF Chronicle
www.experian.com- order your credit report
www.thesarus.com- Thesaurus online
www.miningco.com- Reviews and interesting catagories
www.mtnds.com/af/ - An Acronym finder
www.listfoundation.org – Bay Area resource for jobs, apartments, events
www.nationalgeographic.com – Nation Geographic online
Bookmarks
Bookmarks are the best way to keep track of the Web sites that you’d like to come back to
over and over again. When you bookmark a page there’s no need to keep writing the URL
every time you want to visit it. Its URL is simply added to a menu in Netscape’s menu bar
which you will click upon to return to that site.
Steps to Bookmarking
1. When a Web page you wish to mark is loaded, click the Bookmarks menu.
2. Click Add Bookmark. The menu will drop away.
3. Click Bookmarks in the menu bar again, notice the current page has now been added as
the last item in the list.
Managing Bookmarks
It doesn’t take much Web Surfing before that list of bookmarks becomes unmanageable.
Netscape offers some advanced bookmarking functions under the Bookmarks menu option
by selecting Go To Bookmarks. Here you’ll find a complete list off all the bookmarks you
have added.
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By selecting the File menu option, and selecting New Folder, you can create a series of
folders, much like file management in windows. Now it is just a matter of clicking and
dragging those bookmarks into the selected folder.
Once you’ve created folders for your bookmarks, you can add them to the existing folder
quickly by simply choosing File Bookmark from the Bookmarks menu, finding the folder,
and clicking!
Bookmarking Tips
By selecting File and What’s New? From the Bookmark window you can have Netscape
perform a search of all your bookmarked Web Pages to see if any have been changed since
you last visited them. You may notice the bookmark itself may change, here’s what they
mean:
Normal Bookmark that has been previously visited.
Bookmark that has been entered manually and has not been visited.
Bookmark that has been changed since you last visited that site.
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Searching the Web
You may have found, after clicking on a few random links, that there is no way to find
information on a specific topic unless you accidentally happen upon it. That’s where certain
Web pages called search directories and engines come in. Search engines are services, in the form
of Web pages, that allows you to search for other Web pages through huge databases.
Through an engine you can select a topic of interest or search by keyword, and receive a list
of Web pages relevant to what you are looking for. There are hundreds of engines out on the
Internet, but one of the simplest and most straight-forward is Yahoo! So let’s start with
Yahoo! To familiarize ourselves with Web searching. Yahoo!’s URL is:
http://www.yahoo.com
How to Yahoo!
Once Yahoo!’s page has been loaded, you have two options for searching: searching by a
specific topic, and searching by browsing topics. To search by a specific topic locate the text
entry box next to the Search button, click in it, and type in anything you may want to find
out more about; your pet Labrador, Jimi Hendrix, Tibetan monks, bowling, Learn iT!,
whatever you can think of and click on the Search button. Yahoo! will then look through its
database and return to you a list of ‘hits,’ or links to Web Page’s that Yahoo! thinks you may
be looking for.
Yahoo! also allows you to browse by topic. Notice the Links below the Search Box: Arts &
Humanities, Business & Economy, Education… all these links provide you with a more
specific set of options under that heading. Take some time to get used to Yahoo! by using
both the specific search method and searching by browsing.
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Search Engines
While Yahoo! may get you to Web sites about interesting topics, it is technically not a search
engine. Instead it is called a search directory, which is a passive searching utility. It keeps records
of, and maintains a database of, Web documents (and other Internet resources) that are
submitted to it. Search engines actively search the Internet for information. A search engine
will locate a Web document, capture and store all the information contained on that page,
and follow every link on that page and concurrent pages, storing information as it goes. In
this way, a search with a search engine will be much broader and yield a great deal more
results. The results from a search engine, however, also leave you with a lot more to look
through.
Search directories are best for looking for a general Web site while search engines are best
for finding information on a specific topic. Try a search with Yahoo! and then the same
search with a search engine like Lycos or Alta Vista. See how the results vary. A few of the
best search utilities are listed below. For more, try the Search button on Netscape
Navigator’s toolbar.
Search Sites
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Lycos AltaVista
www.lycos.com altavista.digital.com
Excite Infoseek
www.excite.com www.infoseek.com
HotBot Web Crawler
www.hotbot.com www.webcrawler.com
GoTo
www.goto.com
Refining Your Searches
Since text-based search engines open your searches up to such vast amounts of information,
it is almost always necessary to find ways to narrow your searches. Many of the search
engines, like AltaVista and Lycos, will require you to use special characters in the main
search form to limit or add to your search query. Each search engine should offer tips or a
help section to explain their specialized features, but a few of the common commands are
listed on the next page.
Advanced Searching Tips
• If your search query contains more than one word, use quotation marks to narrow your
results! (examples from AltaVista, altavista.digital.com)
Ex: Golden Gate Bridge will search for everything with golden, gate, and bridge but
“Golden Gate Bridge” will search for the phrase Golden Gate Bridge.
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• Placing a plus (+) sign in front of a search term means that word must appear in the
search results. Like +“Golden Gate Bridge” +traffic.
• A minus (-) sign placed in front of a search term means that word can’t appear in the
search results. Like “Golden Gate Bridge” and traffic but not accident.
In addition to working in the AltaVista search engine, the above examples will help to focus
your search in other text-based search engines like Lycos, Infoseek and Excite. To find
more information on searching the web, find a search engine you like to use, and read the
‘help’ for that specific search engine. Also, yahoo has a listing of all search engines and
directories. If you go to Yahoo’s home page and click on the “Computers and Internet”
link, followed by the “WWW”, then the “Searching the Web” link, you will find links to
search engines and directories, comparisons of search enginds, and information on how to
search the web.
New Search Utilities
Other search engines, like Hot Bot, have begun offering search limitation features through
more user-friendly interfaces. For example, the same search in AltaVista could be completed
using multiple forms, pull-down menus and checkboxes in Hot Bot, no strange characters
required! Here’s an example:
HotBot also allows you to add such advanced queries to your search as the date, location and
media contents of a web page. Other search engines are starting to offer similar services, but
HotBot’s easy-to-use interface still makes it one of the best places to start a search on the
Web.
What’s Next?
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These first two Internet courses have provided you with a solid foundation to use the
resources of the World Wide Web. To learn more you’ll want to take Internet Part 3, the
Advanced World Wide Web. This next class will take a look at ways you can make the most
out of the WWW and become a power surfer. You will learn about Plug-ins for multimedia
on the Web, how to download and install software from the web, and learn how to
configure your Web browser.
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