I f you're new to the world of online communication, you're probably wondering exactly what the Internet is, how the Internet works, and most importantly, what the Internet can do for YOU. (You may have heard the Internet called the Information Superhighway or Cyberspace.) This tour is designed to answer your basic questions about the Internet and show you a sampling of the exciting information possibilities awaiting you when you use Netscape Communicator to investigate the Internet.
The Internet is a worldwide group of public and private computers linked together to exchange information. The Internet evolved out of a group of corporations, governments, universities and research groups that started networking their computers in the 1970s (the first of these networks was established 25 years ago by the United States Department of Defense). Then, as now, the main purpose of the Internet was to share information. No one owns the Internet, nor is it controlled or regulated by anyone. It is a true universal, shared resource.
This shared
information can take many forms, for example, you can use the Internet
to send email messages, read magazines and journals, view sports videos,
make bank deposits, get current news and stock quotes, study great literature,
order products and services, hear the latest underground music, take college
classes, make airline reservations, download games, find a job, look at
a museum's art collection, review current movies--the possibilities are
almost endless. Whether it's education, research, commerce, banking, entertainment,
recreation, or almost any other industry, sharing information is what the
Internet does best.
The Internet offers a variety of services. The two most popular are the World Wide Web (WWW) and electronic mail (email). Other commonly-used services include newsgroups, file transfer, chatting, and searching. The list continues to grow quickly as the Internet becomes more and more an integral part of daily life.
In discussions of the Internet, you may have heard other, similar terms and wondered what they meant. An intranet is a network of connected computers that provides many of the same services as the Internet, but can't be accessed by the public. For example, many corporations have an intranet for their employees. (A firewall is the software or hardware that forms the electronic security barrier between an intranet and the Internet.) An extranet is a private extended intranet that links businesses to corporate partners, customers, suppliers, and so on.
The Internet is made up of an immense network of computers of all different types--from huge government mainframes to networked workstations to your own office or personal computer. Once you're linked to the Internet, you can access files and programs stored on other computers and send email messages to anyone else who has an Internet account.
Physically, the Internet is a vast network of wires. Multiple high-speed "backbone" cables carry information to a series of other network cables (or nodes), which in turn carry information to smaller outlying cables, and so on. The resulting diagram of the Internet would look like a vast overlapping series of finer and finer strands encompassing the globe.
In addition to being physically linked, computers on the Internet need some way to "talk" to each other. The set of rules for interactions between software programs on a network is called a protocol, which is simply a set of standardized communication conventions. Without realizing it, we use protocols every day, for example, dialing an area code before placing a long-distance phone call. Computer protocols define the requirements for packaging the data, for passing control back and forth from computer to computer, and for error checking. One standard, TCP/IP (Transmission Control Protocol/Internet Protocol), has become the universal protocol for transferring data on the Internet.
Here are some other commonly used protocols:
When you send information through the Internet, the protocol breaks it down into smaller pieces. Each piece, or packet, travels through the Internet independently and may even go through different computers before arriving at its destination. Upon reaching their destination, all the packets are reassembled into the original message.
Computers exchange information on the Internet using servers and clients. A server is a computer that stores and manages documents. The server accepts requests from other computers (clients) and then delivers the documents back to the computer that requested them. A browser is the software that runs on a client and interprets the information it receives from the server. The browser component of Netscape Communicator is called Netscape Navigator.
Here's what
typically happens when you sit down at your computer (you're the client),
and click a link or type in a request. The browser on your machine sends
a request to the server you're connected to. The server accepts the request
and contacts the server that stores the information you're asking for.
The receiving server sends the information to your server, which in turns
sends it to you, where you view the document in your browser.
All
you need to be part of the Internet is a computer, a modem, and a phone
line. If you work at home or for a small business, you can establish your
own connection to the Internet through an ISP (Internet Service
Provider). Or, you might be able to connect to the Internet through a LAN
(Local Area Network) provided by your company, school, university, or other
institution.
ISPs are companies that bring World Wide Web access to individuals. The ISP pays for a very high-speed connection to the Internet and then offers you access to that connection for a monthly or hourly fee. Most ISPs provide service through a local telephone line. Once you're connected, you can send and receive email and use all the other Internet services for no additional charge.
Your
Internet Service Provider is your gateway to the Internet. To use the Internet,
you use your modem and telephone line to connect to your ISP's computer
(the server) and log in to your account. When the communication link between
your computer and the Internet has been established, Netscape Navigator
sends your requests to the server. The server does all the work while you
sit back and view the resulting information in your browser. Although the
document you requested might have traveled thousands of miles over high-speed
communications lines, the entire process of requesting and receiving a
file or sending an email message takes only a few seconds. (Well, sometimes
a few minutes if the page contains a lot of images!)
One of the most familiar and fastest-growing parts of the Internet is the World Wide Web. The web is a collection of electronically linked documents that are stored on the Internet. When you use the web, you look at and retrieve Internet information using a click and point graphical interface.
A file that you request on the World Wide Web is called a web page. The pages are made up of text, images, animation, sound files, videos, virtual reality, programs, and data. The elements on a page are sometimes referred to as its content (in other words, web content is any digitized resource that you can access using the Web, regardless of its source or format). A web site is a collection of web pages. A home page is your entry point into a web site.
When you want to view a web page you enter a request for the page using Netscape Navigator. This request is in the form of a Uniform Resource Locator (URL). You can recognize Web URLs by their familiar format of http://www.somecompany.com (seemingly popping up at the bottom of every advertisement or commercial you see). Think of the URL as the address of the page. Once you enter the URL and press Return or Enter, Navigator retrieves the page and you're on your way.
You explore a Web page by clicking on specific areas called links. Links are usually highlighted or underlined so you can find them easily. When you move your mouse pointer over a link, the pointer turns into a hand. When you click the link you automatically jump to the link's destination which could be another place on the page, a different page in the site, or even an entirely different web site.
Links are built on the concept of hypertext because originally most links were words. The "hyper" comes from the non-linear way you jump from idea to idea. Clicking links and moving around is known as browsing or "surfing" the web.
Web pages are written in a formatting language called HyperText Markup Language (HTML). HTML codes (or tags) let authors control the layout of a page, incorporate images, sounds, movies and other media, and provide links to other pages.
While it's great fun to zoom from page to page or site to site,
you also need a way to get back to pages you've already seen or favorite
pages from a few sessions ago. Navigator provides several ways to help
you keep 
track
of where you've been. A history list displays all the sites you've
visited. To return to recently-visited sites, you click Go on the menu
bar and click the name of the page (if it's one of the last 10 sites you've
visited) or you can choose a URL from the Location drop down menu or the
History window. Of course, you can also use the Back and Forward buttons
to move sequentially through the pages you've viewed, but if you've been
surfing for a while, it's usually quicker to use the history list.
While a history list is useful, it can also get very long very
quickly. 
When
you want to be able to return to a site over and over again (or when it's
taken you a while to find the exact page you want), you can create a permanent
bookmark for the page. Bookmarks are your own selective list of
essential or interesting sites. Once you add a bookmark, the page name
appears whenever you click the Bookmarks icon.
Web pages are becoming more interesting, exciting, and interactive every day. Each month new tools appear and pages are quickly moving from boring fields of too-small text to full color, high quality, multimedia extravaganzas. It's this use of media that distinguishes web pages from other Internet services.
The
images, sounds, animations, videos, and virtual reality worlds contained
in a web page are not part of the actual page itself, but are separate
files sent with the pages in which they appear.When a server sends a web
page and its associated files to your computer, Navigator receives and
loads the HTML file first, and then loads the graphics and other multimedia
files. The HTML file controls the layout of the page, including the placement
of all the separate elements.
Graphics files in a web page are one of two types: GIF (Graphics Interchange Format) files or JPEG (Joint Photographic Expert Group) files. You don't need any additional software to view most graphics, however, the files can take a long time to download depending on their size.
To view or hear other multimedia components in a web page, you often need a plug-in or helper application. A plug-in is a small file stored within a special folder inside the Communicator folder that extends the capabilities of Navigator. Plug-ins are distributed by the companies that make the graphics, sound, video, animation, or virtual reality software. Several plug-ins, such as LiveAudio and QuickTime, are automatically installed as part of Communicator. You can add other plug-ins to enhance your experience of Web pages.
A helper application is a separate program that you install on your computer. Unlike plug-ins, helper applications run outside of Netscape Navigator. You can set Navigator to launch a particular helper application when a certain type of file, such as an animation or a sound, appears in a page.
If you've ever looked around on the Web, you know how much information is available there--and how important a good search tool is. On the Web, you use indexes and search engines to help you quickly find the information you are seeking. Indexes let you browse through information by categories, such as sports, arts, entertainment, travel and so on. When you get to a category that interests you, you click and a list of relevant documents appear in your browser.
Search engines work by looking for the one or more words in the millions of Web pages and other documents that they know about. After completing the search, they display a listing of links to the pages on the web that include the text you're searching for. These results are presented in order of relevance, that is, how likely it is that you'll find what you're looking for (usually expressed in a percentage). Some of the better known search engines are Excite, Yahoo!(Yet Another Hierarchically Officious Oracle), Lycos (the name is taken from the first five letters of the Latin name for Wolf Spider), Webcrawler, and Alta Vista. As you get more familiar with search engines you'll learn to enter more and more sophisticated queries, so that you're not inundated by thousands and thousands of search results.
In Netscape Navigator, you click the Search button to go directly to the Netscape Net Search page, which contains links to the most popular search engines.
To quickly search by keyword, enter one or more keywords into Navigator's Location field, and press Return.
To choose from a list of web sites that contain related information, click on the What's Related menu located on the right side of the Location toolbar.
Most Internet service providers give you space on their server where you can store your own files and publish your own web pages. Although it used to be a rather complex process to create a web page, there are now many easy-to-use page authoring tools that can help you quickly design and publish your own web page. The authoring component of Netscape Communicator is called Netscape Composer. You can create any kind of web page, from a personal memoir of your trip through Ireland to a professional catalog for your business.
You use Composer just like a word processor to layout your page and to add the text, graphics, 3D, sound, animations, links, and anything else you like. Netscape Communicator even provides you with a helpful Page Wizard that guides you through the creation process and a set of page templates that you can easily modify for your own pages.
In Composer, you add elements just as you do in other applications, for example, you type in text or place graphics. You see how the page will appear in a browser as you create it. Behind the scenes, the HTML code for the page is being created automatically. Once your page or pages are ready, you need to upload (or transfer) them to your web server. Your ISP can provide you with the information you need to publish your web site.
Perhaps the
most commonly-used feature of the Internet is email. Millions of people
send and receive email every day. It's fast replacing printed mail as the
main method of communication between families who are spread out throughout
the world and is indispensable for business communications.
In addition to simply sending a text message, you can also attach different types of files to an email message including images, word-processed files, sound clips, videos, and applications.
You can also use email as part of a mailing list. These lists allow you to meet and communicate with others who share you interest in a specific topic. To join one type of a mailing list, you send a message to a computer (known as a list server). Once you subscribe, you get every message that everyone sends to the list. Another type of mailing list only sends you messages received from a particular recipient; for exaple, newletters are distributed in this way.
In
Netscape Communicator, you use the Netscape Messenger component to send
and receive email. The messages you receive are stored in your Inbox; you
can create, reply, forward, sort, or delete your messages all from this
one convenient location. Your address book lets you keep your own personal
list of email addresses. You can even bookmark messages if you want to
keep them handy.
As your email volume grows, you might want to consider setting up Messenger to filter your messages. Filtering looks for specific words in incoming messages and then performs the action you indicate, such as storing them in a specific folder (or deleting them immediately!) You can also use Messenger to search your messages by subject, author, content, date, and other search criteria.
People from all over the world participate in online discussions on many thousands of topics in specific areas of interest called newsgroups. UseNet, the world's biggest electronic discussion forum, contains groups for almost every imaginable topic including astrophysics, basketball, calligraphy, divorce, enlightenment, farming, Greek Islands, hot air balloons, infrared photography--you get the idea.
In Netscape
Communicator, the component you use for joining and participating in discussion
groups is called Netscape Collabra.
You participate in a discussion group by reading the messages (sometimes called articles) and responding to them. You can choose to subscribe to a newsgroup, in which case the newsgroup messages will be delivered to your message center. (If you don't subscribe, you have to manually indicate the groups you are interested in each time you want to view the messages.) In moderated newsgroups each message is read by someone who decides which messages will be posted. In an unmoderated newsgroup, all the message are posted.
In many newsgroups, discussions are presented as ongoing threads (discussions grouped by topics). For example, in a newsgroup about bicycles, there could be a thread discussing buying a bicycle, another announcing upcoming races, and a third offering suggestions for biking with kids.
Newsgroups also usually have a list of FAQs (Frequently Asked Questions) that answer basic questions about the newsgroup and can help get started participating in the group.
IRC (Internet Relay Chat) is another way you can share thoughts on the Internet. When you use IRC, you can communicate instantly (chat) with friends and coworkers in other cities, states, or countries without paying long distance telephone charges. Other participants don't hear your voice, but as you type text others can see your words immediately. You can chat with many people simultaneously or you can hold a private conversations with a single individual.
Many chat groups focus on a specific topic. When you join a chat community you are connected into the real-time conversations going on in that group. To add to the fun and mystery, every person uses a nickname. You never know who you might be talking to!
Every day, thousand of users download files, that is, transfer files from Internet servers to their own personal computers. The files can be of several types: text, graphics, software applications, utilities, games, music, video, and so on. In fact, downloading files is a very convenient way to upgrade your software programs or try out new programs, read articles in technical or scientific journals, or study just about any kind of literature.
Files are downloaded using the Internet's FTP (File Transfer Protocol) resource. To log into an FTP site you need an account (usually a user name and password). Some FTP sites let anyone download software, in which case you can often get on the site using "anonymous" as your user name and your email address as your password (these are known as anonymous FTP sites). Other sites are private and allow only registered users to enter the site.
You use FTP software to contact the site. An FTP daemon program on the FTP server handles your request. Within an FTP site you can move through the directories and subdirectories to see the available files. To download the file, you use FTP software that tells the server to send you the file. When you're done downloading files, you log off and close the FTP connection. (You can also use FTP to upload files from your computer to an Internet site.)
Searching FTP sites is becoming easier and easier as more FTP sites begin using web pages as front ends to their sites. The user-friendly interface of a web page displays the file names and includes a description of the file and even suggestions on when to use the file. The file icon is a link, and when you click the link, the file is downloaded (FTP operates behind the scenes to bring you the file).
The biggest problem with downloading files is that if the file is large, it can take a long time to download. Even with a fast modem (14.4 kps or faster), large files can take several minutes or even hours to download. To speed up downloading, many files are compressed when they're stored on the server. After the file is downloaded you use compression software on your computer to decompress or expand the file. Two of the most commonly used compression packages are WinZip and Stuffit. You can recognize compressed files by their file extensions, .zip, .sit, or .sea.
Just as you need to respect the copyright of printed material, you must also be aware of the legal limits that apply to files you download from the Internet. Files that are in the public domain, don't have any restrictions. For example, the works of Shakespeare are all in the public domain. Freeware and shareware files are copyrighted, but require little or no fee for use. Programmers often distribute their work as freeware or shareware on a tryout basis or when they want to get feedback on their work. Both freeware and shareware have specific rules for use and distribution. To see some examples of shareware, visit the c | net Shareware Page at http://www.shareware.com/.
Every packet of information that travels around the Internet goes through many different public networks. This means that lots of people have access to the information. There are times, however, such as when you're ordering something and paying with your credit card, when you want the information to remain private.
To protect your information you use specific security tools. One of these software tools, encryption, encrypts (or codes) the information when you send it so that it looks meaningless to the average person. Only the designated recipient, who has the software to decrypt the information, can read it. Netscape Communicator uses SSL (Secure Sockets Layers Protocol) to enhance Internet security. This public key encryption system uses pairs of digital keys (random strings of bytes) to protect the information. Your server site has one pair of keys and your computer has one pair of keys. The information is passed over a secure connection and then encrypted to protect the contents.
SSL also provides another level of security with site certification. Site certification means that every secure server must request and receive a unique digital certificate, which ensures that the site sending you a message is who they say they are (this information is called signed data).
To help you use security effectively, Communicator lets you know when you're entering or leaving a secure site, when you're viewing encrypted data, or when you're about to send unencrypted information to a site. In this way, you're prevented from revealing private information unknowingly.
Netscape Communicator also allows you to have personal certificates that identify individuals who send information. Personal certificates are necessary when you want to send and receive encrypted email or access secure sites without a password. In Communicator, you set up your security preferences and check the security of Web sites using the Security button.
With the information you've gained from this tour, you're ready to jump on your surfboard and hit the (virtual) beach. In your travels, you'll find more interesting things than you can possibly imagine and this constantly expanding wealth of information will provide you with countless hours of knowledge and entertainment. Enjoy the ride!