The Internet

At a Glance

Instructor’s Notes

Chapter Overview

In this chapter you will learn how the Internet works. You will learn how to use a dial-up connection; learn the differences between an IP address, domain name, URL, and e-mail address; and learn the power of a Web browser. You will also compare push and pull technologies, understand synchronous and asynchronous interactions, learn the purpose of HTML tags, and evaluate the effectiveness of Web page designs.

Lecture Notes

Key Terms

We define the Internet as a network of networks. Use Figure 8-2 to understand this concept.

Data travels on the Internet backbone, which consists of the major Internet communications links. The roadmap analogy (Figure 8-3) is an easy way for you to understand this concept, and for you to understand why at times the Internet seems slow (if Internet traffic is high).

The Versatile Web Browser

The World Wide Web (usually just called "The Web") is probably the most popular Internet service. The Web is based on ideas that originated with Vannevar Bush in the 1930s, later called hypertext by Ted Nelson. The Web is a vast collect of documents, graphics, digitized video clips, and sound files that can be accessed by following links. Refer to Figure 8-8. To access the Web, you need to use Web browser software.

Web pages include multimedia elements; the way you view and see these elements rely on the type of technology the Web server uses. Streaming media sends small segments of the file at a time, in-place multimedia technology plays a media element as a seamless part of a Web page, and multimedia overlay technology adds a separate window in which multimedia elements appear.

Downloading from the Web is an easy, straightforward procedure, but uploading may prove to be more problematic.

Web portals are a helpful way for you to find Web pages, chat, and access e-mail.

The model for commercial information services is a mainframe host accessed by terminals or microcomputers with terminal emulation software(the software provided by the commercial information service). The big advantage of these services:

• They provide a comprehensive software package for subscribers.
• The information is managed and organized to some extent.

Web Authoring and Site Management

As the Internet continues to gain in accessibility and popularity, more people are realizing they can receive and obtain information by publishing on the Web. Creating a Web page has never been easier, whether it’s creating a simple page to a more complex series of linked Web pages that contain multimedia elements.

Understand that a Web page is an HTML document, which looks similar to a computer program. Refer to Figure 8-17 to see what a Web page looks like as an HTML document. Luckily, you do not need to memorize HTML codes to create a Web page. You can use software packages such as Microsoft Word, Web browsers, and specialized Web authoring software.

To help you understand the different types of hypertext document formats, refer to the chart below.
 

An effective Web page is a planned, well-designed one. Review the Web page design tips on pages 367-368.

E-commerce is an increasingly popular way of doing business. Many may worry about security on e-commerce sites. Review the difference between secure and non-secure sites. Consider the benefits and drawbacks of using e-commerce sites.  Remember that establishing an e-commerce site can be a good way to build a clientele for a small business venture, or to test the market with new product ideas.
 

User Focus: Connecting to the Internet

The purpose of this section is to give you an idea how to connect your own computer to the Internet. Students who may be familiar with using the Internet may, in fact, have no idea of how that connection occurs.

An issue that often arises is that of speed. Many wonder why some pages load more quickly than others, or why some sites seem slower during certain times of the day when the speed of their modem remains constant. Review  the difference between connection speed and transfer rate and understand the reasons why data is not always transferred at their modem’s highest speed.

Issue: Is the Truth Out There?

From urban legends to phony e-mail, the Internet brings users into contact with unreliable information on a regular basis. Read this issue for information.

Data Security

At a Glance

Instructor’s Notes

Chapter Overview

In this chapter you will learn about threats to the data stored on computer systems, such as lost and missing data, damage caused by power problems and
hardware failures, and viruses, and how to protect data from these threats. You will also learn about risk management.
 

Lecture Notes

Key Terms

     Acceptable use policy (407): A set of rules and regulations that specify how a computer system should be used.

     Antivirus software (403): Software that examines files stored on a disk to determine if they are infected with a virus.

     Backup (420): A copy of one or more files and folders on a disk.

     Backup software (421): Manages hard disk backup to tapes or disks.

     Biometrics (410): A method of personal identification based on some unique physical characteristic.

     Boot sector viruses (398): Infect the system files your computer uses every time you turn it on, causing widespread damage and persistent
     problems.

     Checksum (403): A value that is calculated by combining all the bytes in a file; each time you run the application program, the virus detection
     program recalculates the checksum and compares it to the original to determine if a virus is present.

     Computer virus (397): A program that attaches itself to a file, reproduces, and spreads from one file to another.

     Cookie (415): A message sent from a Web server to your browser and stored on your hard disk.

     Copy Disk (420): A program that duplicates the contents of an entire floppy disk.

     Copy utility (420): A program that copies one or more files.

     Crackers (396): People who vandalize computer data. Also called hackers or cyberpunks.

     Cyberpunks (396): People who vandalize computer data. Also called hackers or crackers.

     Data security (406): The collection of techniques that provide protection for data.

     Differential backup (423): A copy of all the files that have changed since the last full backup.

     Digital certificate (414): Identifies the author of an ActiveX control.

     Downtime (416): Time period in which a computer system is not functioning.

     Encryption (412): The process of scrambling or hiding information so it cannot be understood until it is changed back to its original form.

     End-user procedures (407): habits, formalized and adopted by an organization, that significantly reduce the chance of operator errors.

     File virus (397): A virus that attaches itself to an application program.

     Firewall (414): A technique used by companies with hosts or LANS to screen out potentially hostile programs.

     Full backup (422): A copy of all the files on a disk.

     Hackers (396): People who vandalize computer data. Also called crackers or cyberpunks.

     Hardware redundancy (416): Maintaining equipment that duplicates the functions critical to computing activities.

     Incremental backup (424): A copy of the files that have changed since the last backup.

     Java applets (414): Small programs that are intended to add processing and interactive capabilities to Web pages.

     Key (412): A "decoder ring" necessary for the encryption or deciphering of data.

     Logic bomb (400): A computer program that is triggered by the appearance or disappearance of specific data.

     Macro (398): A miniature program that usually contains legitimate instructions to automate document and worksheet production.

     Macro virus (398): Infects documents, such as those created with a work processor.

     Mean time between failures (MTBF) (394): A duration measurement of the reliability of computer components.

     Operator error (392): A mistake made by a computer user.

     Payload (397): The ultimate mission of a virus.

     Power failure (393): A complete loss of power to the computer system.

     Power spike (393): An increase in power that lasts less than a millionth of a second.

     Power strip (394): Strip resembling a surge strip, but without the electronics necessary to filter out power spikes and surges.

     Power surge (393): An increase in power that lasts about a few millionths of a second.

     Pretty Good Privacy (PGP) (413): A popular and easy-to-use public key encryption system.

     Public key encryption (PKE) (413): An encryption method that uses a pair of keys, one public key known to everyone and a private key known
     only to the message recipient.

     Risk management (406): The process of weighing threats to computer data against the amount of data that is expendable and the cost of
     protecting crucial data.

     Sandbox (414): A secure area of your computer.

     S-HTTP (Secure HTTP) (415): Encrypts data between your computer and a Web server, but does so one message at a time.

     SSL (Secure Sockets Layer) (415): Uses encryption to establish a secure connection between your computer and a Web saver.

     Surge strip (394): An inexpensive device that protects your computer equipment from electrical spikes and surges.

     Time bomb (400): A computer program that stays in your system undetected until it is triggered by a certain date or time.

     Trap door (411): A special set of instructions that allows a user to bypass the normal security precautions and enter the system.

     Trojan horse (399): A computer program that appears to perform one function while actually doing something else; type of computer virus.

     Uninterruptible power supply (UPS) (393): A device containing a battery and other circuitry that provides a continuous supply of power.

     User rights (411): Rules that limit the directories and files that each user can access.

     Virus signature (403): Unique series of bytes that can be used to identify a known virus.

     Worm (401): A program designed to enter a computer system (usually a network) through security "holes."

     Y2K bug (400): A problem with software that does not require a four-digit date field.

What Can Go Wrong

In the first part of this chapter, we look at the sources of problems which can compromise data security and confidentiality including operator error, power failure, hardware problems, computer viruses, and computer crime.

Computer users make mistakes—some of them are very costly. You probably already have your own favorite stories to tell. It is fair, however, to present a balanced picture of operator error. Some new computer users are so afraid of making errors and losing data that it inhibits them from healthy experimentation. The operative word is "THINK"—realize that it is important to stay focused on the task at hand and think about commands before you activate them.

Power problems can erase data and damage equipment. Make sure you understand the difference between an uninterruptible power supply and a surge strip.

If you are technically oriented, you might know that what is commonly called an uninterruptible power supply is more correctly a battery backup, characterized by the need to switch to battery power when the regular power fails.

Hardware fails. Unplug their home computer systems from the wall outlet and to disconnect the modem line from the phone jack on the wall during thunder or lightning storms. A surge from a lightning strike could very easily ruin a computer system.

Another point: Although you can purchase an insurance policy to cover your computer and data, this policy cannot restore damaged data. Your best "insurance" is regular backups.

Viruses and Other Pesky Stuff

The language that pertains to computer viruses is vivid, but sometimes used without precision. For example, the term "virus" is sometimes used when the term "worm" would be more appropriate.

Figure 9-4 shows a fake virus alert. You might want to review this figure and its callouts.

You might want to use Figure 9-5 to review how a virus spreads. You might also want to compare with the students the different types of viruses and how they are spread and triggered.

Some of you might have heard of a new virus development in certain Microsoft products, in which a virus appears to attach itself to document files. The virus actually attaches to a macro (a program that can be run), but the upshot is that today, even data files are not safe from infection. You can learn more about this virus on Microsoft's Web site.

Antivirus software, while not foolproof, is a good way to protect your computer form damage by viruses. While many  may be familiar with
the concept of antivirus software, many will not be aware of the recommendations for software updates. Realize that in order for virus software to
remain current it must be updated every three months.

Risk Management

The first sections of this chapter examined causes of data loss. This section provides guidelines for minimizing the risk of data loss. Risk management is the process of weighing threats to computer data against the amount of data that is expendable and the cost of protecting crucial data. You can review the four steps in the risk management process on page 406.

Acceptable use policies are rules and regulations that specify how a computer should be used. Of course not everyone adheres to policies, leaving the door open for misuse and abuse both from authorized and unauthorized personnel.

End-user procedures are guidelines for performing specific tasks. Theoretically, if procedures are followed, operator error will be greatly reduced or
eliminated. Of course, not everyone follows procedures, and procedures might not be available for all tasks. Therefore, procedures provide only one
line of defense for data security.

Restricting on-line access to data is done by (1) requiring user IDs and passwords to use the system, (2) limiting the rights to use certain programs or
data depending on a user's ID, (3) closing all trap doors into the system.

Even if data is stolen, it cannot be used if it is encrypted. The topic of modern encryption is fascinating, though beyond the scope of this textbook.

Virus detection software finds and eradicates many viruses, but it is not 100% reliable. Polymorphic viruses change themselves—their program code—to avoid detection by their signature. Stealth technology enables viruses to hide from detection software in other ways. For example, a virus might trap a system call that would read the section of memory that it (the virus) occupies. Another technique is for a virus to cloak its size from the operating system, so it is not apparent that the virus has attached itself to an executable file and increased its size.

You should be aware of the dangers involving Internet transactions, and what they can do to prevent or lessen these problems. Hackers can use Java applets and Active X controls, both of which are intended to add processing and interactive capabilities to Web pages, to cause havoc with your computer system.

Redundancy cannot prevent data loss, in most cases, but it can quickly get a computer back into operation after an equipment failure.

User Focus: Data Backup

Review the recommendations on page 417 for creating your own backup plan. Figure 9-20 provides an overview of the relative advantages and disadvantages of a number of backup media.

Use Figures 9-23, 9-24, and 9-25 to explain the different types of backup procedures. Some have difficulty distinguishing between differential and incremental backups. A differential backup backs up all the files that were changed since the last full backup. An incremental backup backs up only those files that were changed since the last backup of any type. With a differential backup, you use only two tapes—one to hold the full backup and one to hold all the changes since that full backup. With an incremental backup, you use a series of tapes—each tape contains the incremental changes that were made since the previous tape.

Issue: Is It a Crime?

As the section emphasizes, our society seems undecided on how to approach hackers. On one hand, laws are in force that require criminal penalties for hacking into computer systems; on the other, computer hackers are often glorified in movies and on television.

The Internet: World Wide Web
Data Backup

Overview
The Internet is a WAN linking millions of computers in LANs worldwide. Special protocols are used for the Internet which enable it to work across any kind of
network, and browsers to access the Web have made it user-friendly.

The software used to access the Internet includes clients which request information and servers which deliver it.  Services on the Internet include email, the Web,
FTP, chat, and Internet telephony.  Much of the content on the Internet is freely available, but some is provided by online services which charge for access to their
proprietary network content.

Computers directly connected to the Internet have a unique IP address and an equivalent domain name which is easier to remember.  Companies have begun to use
Internet tools such as email and Web browsers to access their own internal communication and information systems, because these tools are so widely known.
Access to the Internet also allows companies to use it as a medium to distribute information both within the company and to outside clients.

The increasing traffic on the Internet will require more addresses and higher bandwidth.

Lecture Notes
Introducing the Internet:  The Network of Networks
The services provided by the Internet are another example of convergence, as discussed in earlier modules.

The Internet network of networks structure is similar to the telephone system in which local subscribers are linked by a local company, but long distance lines link the
local companies.

A "Galactic" Network
The "IP" in "IP address" stands for Internet protocol.

Many computers which use the Internet are not "fully connected" with their own IP address.  Instead, they access a computer which is fully connected.  Thus, the
Internet is a network of fully connected machines which in turn have their own networks of machines which use them to access the Internet - a "network of
networks."

Interoperability
The ability for one computer to ask another to display information, download a file, accept and store a mail message, etc. is the basic principle of the Internet.
However, the control that one machine has over another on the Internet must, of course, be limited to the functions that the owner of the controlled machine is willing
to allow.  Not just any files can be downloaded, for example, but only those which are specifically made available for this purpose.

Leave the Lower Layers to the LANs and WANs
The concept of a protocol stack, as covered in earlier modules, isolates the mechanics of the physical transmission of data from the way data is presented to the
computers and applications at either end of an Internet connection.

The Internet vs. Online Services
Even some users who have other Internet access, such as through their employer or an independent service provider, may choose to use an online service, too.  An
online service usually offers local phone numbers to connect to the service, and the Web, from many cities and countries, which makes Net access available away
from home without a long-distance change to access your regular provider.

AOL's customer base was built largely by giving away millions of free disks or CDs which installed AOL access software and provided a free trial period for the
service.  This proved to be an appealing, cheap, and easy way for novices to "see what the Internet was all about" and many became regular AOL customers.

Portals, which are Internet sites that provide services and content similar to that of online services, are supported not by users' fees but by advertising on their sites.

The Internet's History
Using the ARPANET formerly required a user to register with a central authority. Today, anyone can use the Internet without registering. However, the company or
organization granting you access typically is responsible for your behavior, and so usually some local registration or application is required (possibly in electronic
form).

The Internet was designed with no central office or computer because the Internet designer's were told to think of the possible consequences of a nuclear attack. If
an enemy attack were to take out a node of the Internet, it is designed to route around the destroyed node and not be crippled.

Internet Software:  Clients and Servers
The client/server concept is rapidly becoming the dominant form of network organization.  Make sure that students understand the differing roles of the server, which
provides information, and the client, which requests it.  The client can only request the types of information that a given server is set up to provide and can only make
requests follow the appropriate protocols.  Most of the processing needed to provide information is done by the server, not the client.

Exploring Internet Services
Electronic Mail (Email):  Staying in Touch
Email is popular in part because it is both faster and cheaper than conventional mail, but it provides a hard copy if needed, unlike the telephone.  Many people also
like to send email messages instead of using the telephone because they can compose the message carefully and send it to multiple recipients at once.  Some people
prefer to get email message instead of phone calls because they are less interruptive;  emails can be opened and read at the receiver's convenience.
Although you will receive notification if an email message cannot be delivered, you cannot know for sure if or when the addressee will open and read the message.

The World Wide Web (WWW): Accessing Information
The Web is probably the best-known and most widely-used Internet service.
The hypermedia of Web documents is created using HyperText Markup Language (HTML). Another module explains in greater detail how to use HTML.

Web navigators include Internet Explorer, Netscape, MacWeb, and Lynx. Lynx is unique in that it follows a text-based interface to WWW; the interface doesn't
require a mouse and will run on any dumb terminal (or PC emulating a dumb terminal); however, you can't view graphics or listen to sound with it.

FTP:  Transferring Files
FTP client programs enable you to connect to FTP server programs running on computers on the Internet. Both Macintosh and PC-compatible machines can be
servers.

Public file archives get around the user-password problem by providing the special user "anonymous," and they request you to enter your e-mail address for the
password so that they have an idea about how many users from other sites are accessing their server.

Companies that produce software use FTP servers to provide updates and bug fixes to their customers. Although anyone can download the updates, they are not
the entire program, rather just something that will update the program a customer already owns.  Like Internet Explorer 5.0, Netscape Communicator can upload
files.

Sidebar:  A Taxing Question
There are two aspects to taxation of the Internet:  taxing the provision of Internet services in general, and applying sales tax to the goods and services purchased on
the Net.

Taxing services is a long-established policy in some jurisdictions, although specific laws vary from state to state, so there is no reason in principle why it should not
apply to Internet services.  There remain practical problems, such as the understandable tendency of Internet suppliers to leave high-tax states or areas for lower-tax
areas, but these problems have arisen in other taxed industries as well, and states and municipalities have learned to balance the need for revenue with the need to
encourage business.

Collecting sales tax on goods and services bought over the telephone or by mail order presents  many of the same issues as Internet purchase taxes.  States'
experiences with these taxes can be used as a guide on how to proceed with Internet sales.

Usenet:  Joining Online Discussions
Usenet originally was based on systems that periodically telephoned one another and exchanged articles that hadn't been received yet via modem. Some systems
were connected directly and exchanged information more frequently. Today, most large-volume systems are directly connected.

Newsgroups can be created or destroyed; creation involves a "vote" by electronic mail after a period of discussion. Some special types of newsgroups can be
created by anyone for any reason, but these aren't always taken as seriously as ones created through the formal process. Articles are also called posts or postings.

Computer programs, images, and sounds can be specially encoded using standard letters and numbers and sent through electronic mail or through the Usenet
system.

Some newsreaders present all articles on a given thread at one time, but others present articles in the order in which they arrive at your system. Remember that
articles are submitted from all over the world, so this order will be different for each system.

IRC:  Text Chatting in Real Time
Chat services similar to IRC are available at various Web sites.  These may be accessed using standard Web browsers and mouse interfaces with which users are
already familiar, while IRC channels require a special client.  IRC clients can be downloaded from the Internet.

Some of the Web-based chat is not text-based only but uses visual depictions of the chatters called avatars which move around and interact on screen in scenes
called "virtual worlds."  The avatars are not actual likenesses of the people chatting, but may be animals, robots, fantasy creatures, or caricatures.

Internet Telephony:  Real-Time Voice and Video
While these services are relatively primitive today, there is every reason to believe that quality will improve as PCs become faster and more powerful, and higher
bandwidth connections more readily available.

At the same time, new protocols and network designs will help deliver voice and video. Some new protocols already available compress data for faster transmittal
and then decompress it at the receiving computer.

The combination of these various developments may lead to Internet telephony becoming a new standard communication device.

More Internet Services
MUDs are similar to IRC channels or Web chat rooms, but were designed for players of "Dungeons and Dragons" type fantasy games.  Accessing MUDS requires
Telnet.  Telnet is an Internet service that enables you to access libraries, databases, and other public services all over the world. Hytelnet is a tool that helps you
access the various sites through Telnet.

How the Internet Works:  A Geography of Cyberspace
Configuring Your Computer for Internet Access
In general, any computer purchased today will have full Internet support built in for at least regular dial-up service.  If you are building your own computer, or trying
to upgrade an older model, you will need expert advice.

Accessing the Internet
Dialup access usually means that you use a terminal emulator or communications package on the personal computer. The clients for FTP, e-mail, and the like, all run
on the computer your personal computer has dialed.

Direct Internet access allows the client software to access various resources on the computer in front of you.

Dialup IP access is not faster than dialup access; in fact dialup IP is usually slower due to the overhead incurred by the TCP/IP protocols. Dialup IP access also
requires a special dialup server that can "attach" your remote personal computer to the network after you dial in.

A local area network connection offers much higher data rates, as does a connection via ISDN.
Internet Service Providers (ISPs)

ISPs are found in most communities-check your local phone directory.  Small communities may not have a local ISP.  In this case, dial-up access to the ISP will
require a long distance call, which can make access prohibitively expensive.  Cable and satellite access may be alternatives in these cases.

If you have access through your employer or college, you may not need an ISP because you may be able to dial in to the employer's or college's network for access.

Backbones
Backbone networks enable messages traveling long, common routes (such as New York to Los Angeles) to take an "express line." Backbone networks may have
multiple lines between the same two points to provide redundancy in case of failure, as well as providing more capacity.

The Internet Protocols (TCP/IP)
Internet protocols are the standards that enable computer users to exchange data through the Internet. Protocols determine how data packets are layered or
packaged into small packets for transmission. Most hardware and software developers subscribe to a standard set of protocols called OSI (Open Systems
Interconnection) that consists of seven layers of protocols for worldwide computer communications.

Low-level Internet protocols are formal ways for computers to exchange information reliably. (At a still lower level are the physical signals between the computers.)
At a higher level are protocols for sending electronic mail (Simple Mail Transfer Protocol-SMTP) and for exchanging other forms of information.

The Domain Name System
Domain names are meant to make it easier to refer to or locate Internet sites, but some domain names do not access the site that you might expect.  That is because
domain names can be registered by anyone, not necessarily by the organization that might have that name or trademark.  For example, http://www.alamo.com does
not take you to the Web site of the famous building in San Antonio Texas, nor to Alamo Car Rental, but to another firm in Texas with a completely different name.

If you type a domain name into your browser and get an error message, there may be several reasons, including a typographical error on your part, an error in
accessing the domain name server, trying to access a server which is protected by a firewall, or a temporary (or permanent) problem on the server you are trying to
access.

Intranets:  Using TCP/IP Inside the Enterprise
Internal intranets which operate behind secure firewalls are the fastest-growing part of the Internet today.  They are favored by businesses and organizations for their
internal use because they are cheaper to set up and to run than networks based on proprietary protocols. In addition, users can navigate intranets using browsers and
tools they are already familiar with from the World Wide Web.

The Future of the Internet
More Internet Addresses
In "IPv6," the "v6" stands for version 6 (the current version is 4) and it is also known as "Ipng," where the "ng" stands for "new generation".

It is anticipated that the two versions will coexist for some time, with the new protocol gradually taking over as more users convert to equipment which can handle it.

More Bandwidth
The federal government, which financed the development of the original ARPANET from which the present Internet grew, is now financing development of improved
networks; however, the availability of more bandwidth may also create more demand for services and permit the development of new clients which require more and
faster data transfer.  The development and expansion of Internet technology to meet demand may be a never-ending task.

Overview
The terms World Wide Web and Internet are often used interchangeably. In fact, the World Wide Web is software technology used on the Internet.  One of the
main features of Web technology is hypertext, which enables users to navigate by clicking on text or graphics which are linked to other areas of a Web site or to
other Web sites.

With the advent of the WWW, new terms and concepts were, and continue to be, conceived. In addition,  new ways to research information, communicate with
others, and educate oneself by visiting sites around the world are evolving.

Because the volume of information available on the WWW can be, and often is, overwhelming for computer users, search engines are available to assist in locating
specific topics of information.  Just as information from print sources can be incorrect, biased, or misleading, information from the Web should be critically evaluated
before it is accepted.

Lecture Notes
Welcome to the Web
The Hypertext Concept
A new language has evolved with the development of the World Wide Web. The concept of hypertext is actually older than the Web itself, and originated in the
article "As We May Think," by Vannevar Bush, published in The Atlantic in 1945. Hypertext documents are documents that contain information and references or
links to other documents that contain information related to the present document. These links are called hyperlinks. Hyperlinks are graphical elements or special text
used to link any Web page to another.

Web Browsers and Web Servers
The software that enables you to go from one resource to another by following these hyperlinks is known as a Web browser.  When using the Internet, you are
reading documents displayed in a Web browser. The overall structure of Web technology is client-server architecture, which involves two computers: the server
where the information that the user accesses is actually stored and the client computer running software that allows you to access the information. The client gets
information from the server by means of a transaction. The documents sent by the server to the client are written in HTML, HyperText Markup Language.

Some sites may have a message stating that the site is best viewed with a particular browser.  This message does not mean that other browsers can't access the site,
but it may mean that certain HMTL features or software commands have been used at the site which only one browser can correctly process.  Many people have
copies of both major browsers (Microsoft and Netscape) for this reason, although they make one of the two their "default" browser to access the Web
automatically, unless the other is specifically wanted.

Web Addresses (URLs)
URL, Uniform Resource Locator, is a code developed to identify resources on the Internet. A URL is similar to the library catalog call number of a book. The URL
has three components-the tool used to access the resource (Telnet, FTP, etc.), the address of the computer on which the resource is located, and the optional path
name of the resource itself.

Web Protocols
HyperText Transfer Protocol, HTTP, is the protocol (standards for exchanging information) of the WWW. A document you create that can be accessed by a Web
browser is called a Web page or Web site. HTML, HyperText Markup Language, is used to transmit documents that can contain different media formats in the
same document.

Web Page Design Tools
Module 8B contains specific information on how to design a Web page with HTML.

Sidebar:  The Birth of an Industry
Netscape is another of the companies (such as Oracle, the database firm discussed in an earlier module) that are part of entirely new industries that have grown up
around the computer.  The growth of these industries is part of the reason for the shift in employment patterns in the United States towards more jobs which require
workers with technical skills and training.

Today, Microsoft's Explorer browser software is providing strong competition to Netscape. Like Netscape, Microsoft Explorer is given away free, but because
Microsoft is able to place a free copy of Explorer on the desktop of each new PC which comes equipped with Windows, Netscape has charged that Microsoft has
an unfair trade advantage.  This dispute has become a legal issue whose outcome remains undecided at the time this book is being written.

Browsing the Web
The best way to learn to use the Web is to jump in and start, but many students who are already users may not be familiar with all of the tools available.  For
example, many users do not know how to organize their bookmarks.

Finding Information on the Web
To find information on the World Wide Web, you may need to use a search tool.  Search tools can be categorized as subject directories or Web databases. Subject
directories are manually compiled by staff of the directory and by users who submit entries. Web databases are compiled by software "robots" or intelligent agents
that roam the Web and collect information for the databases.

There are several popular subject directories that allow you to search or browse for a variety of subjects.  These include Yahoo, the World Wide Web Virtual
Library, Alta Vista, and Infoseek.  Yahoo means Yet Another Hierarchy and also refers to the database's authors who claim to be yahoos. With Yahoo, you can
select a category and view a list of related Web sites, search the entire database, or select other lists.

The World Wide Web virtual library is the oldest Internet subject directory. An advantage of this tool is the expertise of the individuals who maintain a specific
subject directory. A disadvantage of the World Wide Web virtual library is that the organization of subjects does not let you search the entire WWW virtual library;
moving from one subject to another can be awkward.

Alta Vista is one of the newer Web databases. Alta Vista has the ability to index over 16 million Web pages. Alta Vista provides both simple and advanced options,
including Boolean operators.  Infoseek Guide is a search tool that uses both database and subject directories.

Search Techniques
Basic knowledge about using search engines is essential to the success of using the WWW. In addition to searching for specific terms, Boolean logic can be used to
combine search terms in different ways. AND, OR, or NOT operators assist users in describing the logical relationship between two or more search terms.

Words that describe a search topic are known as search items. Hits are returned items that match your search terms.  Results ranking is an attempt to put the
resources returned by the search in an order based on each resource's relevance to a query.

Evaluating the Information You've Found
Information located on the Web must be evaluated critically, just as you would evaluate information from any other source.  In fact, information published on the
Web may be  somewhat less likely to be trustworthy than information from books, magazines, or major media outlets such as television networks.  As stated in the
text, this is because information from traditional media usually must meet standards set by law or by the corporations which typically own media outlets.

In contrast, publishing information over the Web is relatively easy and inexpensive, so individuals who would not have access to major media can set up a Web page
and make statements or claims that may be read by a huge audience, all without any outside check on the accuracy of the statements or claims being made.

Overview
As publishing a basic Web page has become easy, thanks to HTML tools and Web-integrated applications, more and more people are becoming active participants
in the Web by publishing their own pages.  In addition, more businesses are using the Web to publish information internally, so employees with Web publishing skills
have an advantage.  This module teaches students to create a simple Web page.

Lecture Notes
The Web Publishing Process
In order to insert information on the World Wide Web for others to use, you need to create a Web site or a Web page. A Web site is the umbrella organization of
your home page and Web pages.

Defining Your Purpose
To access the World Wide Web, people need a computer, a modem, a telephone line, and an Internet service provider or online service.

Choosing an HTML Editor
Using a text editor requires you to learn the mechanics of how tags function and therefore is appropriate for learners.  However, experienced Web page authors
usually move to semi-automated software such as a site manager which reduces the amount of typing required and the chance of errors in tags.

Making Design Decisions
Web designers should be aware that browsers, monitors, and computers vary, and that therefore the design they create may not appear the same to everyone who
may access it later.  A common design error is to create a page that is too elaborate;  in general, simplicity translates best on a variety of equipment.

Creating Your Page
Explain to students that the <BR> element will cause the browser to break the text flow at that point.  The next text will start on a new line, one line below the
previous.  This is in contract to <P>, which will break the text, skip a line, and then begin new text on a new line.  Attempting to control spacing or new lines with the
Enter key may look right on the composing screen, but will not print out correctly with a browser.

Sidebar:  The Growth of XML
The limitations of HTML may not be apparent to new Web authors but will soon become frustrating to experienced ones.  XML allows much more freedom for
authors, but since older browsers cannot interpret XML pages, Web developers must be careful about designing pages that may be available to only a limited
audience.  Techniques that provide both XML and HTML versions of a page will help during the transition to XML.

Testing Your Page
The appearance of a page as you are composing it in an HTML editor, word processor, text editor, or other software may not be reliable.  The page may be
displayed differently with a browser because browsers recognize only a few formatting features.  You must always view the page with a regular browser to check its
appearance.

Publishing Your Page
Students who would like to publish a Web page may want to look into one of the several sites on the Web which provide free page publishing for users who
register.  These sites are supported by advertising and have memory space limitations, but they have plenty of room for a number of pages.

Web Publishing Horizons
Web publishing will continue to grow as both a personal pastime and a professional career.  Students who are interested in writing or design would be well advised
to learn something about Web publishing, as it will enhance their skills and employability.