1. A Basic Guuid to Internet
The
Internet is a computer network made up of thousands of networks
worldwide. No one knows exactly how many computers are connected to the
Internet. It is certain, however, that these number in the millions.
No
one is in charge of the Internet. There are organizations which develop
technical aspects of this network and set standards for creating
applications on it, but no governing body is in control. The Internet
backbone, through which Internet traffic flows, is owned by private
companies.
All computers on the Internet communicate with one
another using the Transmission Control Protocol/Internet Protocol
suite, abbreviated to TCP/IP. Computers on the Internet use a
client/server architecture. This means that the remote server machine
provides files and services to the user's local client machine.
Software can be installed on a client computer to take advantage of the
latest access technology.
An Internet user has access to a wide
variety of services: electronic mail, file transfer, vast information
resources, interest group membership, interactive collaboration,
multimedia displays, real-time broadcasting, shopping opportunities,
breaking news, and much more.
The Internet consists primarily of
a variety of access protocols. Many of these protocols feature programs
that allow users to search for and retrieve material made available by
the protocol.
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COMPONENTS OF THE INTERNET
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WORLD WIDE WEB
The
World Wide Web (abbreviated as the Web or WWW) is a system of Internet
servers that supports hypertext to access several Internet protocols on
a single interface. Almost every protocol type available on the
Internet is accessible on the Web. This includes e-mail, FTP, Telnet,
and Usenet News. In addition to these, the World Wide Web has its own
protocol: HyperText Transfer Protocol, or HTTP. These protocols will be
explained later in this document.
The World Wide Web provides a
single interface for accessing all these protocols. This creates a
convenient and user-friendly environment. It is no longer necessary to
be conversant in these protocols within separate, command-level
environments. The Web gathers together these protocols into a single
system. Because of this feature, and because of the Web's ability to
work with multimedia and advanced programming languages, the Web is the
fastest-growing component of the Internet.
The operation of the
Web relies primarily on hypertext as its means of information
retrieval. HyperText is a document containing words that connect to
other documents. These words are called links and are selectable by the
user. A single hypertext document can contain links to many documents.
In the context of the Web, words or graphics may serve as links to
other documents, images, video, and sound. Links may or may not follow
a logical path, as each connection is programmed by the creator of the
source document. Overall, the Web contains a complex virtual web of
connections among a vast number of documents, graphics, videos, and
sounds.
Producing hypertext for the Web is accomplished by
creating documents with a language called HyperText Markup Language, or
HTML. With HTML, tags are placed within the text to accomplish document
formatting, visual features such as font size, italics and bold, and
the creation of hypertext links. Graphics and multimedia may also be
incorporated into an HTML document. HTML is an evolving language, with
new tags being added as each upgrade of the language is developed and
released. The World Wide Web Consortium (W3C), led by Web founder Tim
Berners-Lee, coordinates the efforts of standardizing HTML. The W3C now
calls the language XHTML and considers it to be an application of the
XML language standard.
The World Wide Web consists of files,
called pages or home pages, containing links to documents and resources
throughout the Internet.
The Web provides a vast array of
experiences including multimedia presentations, real-time
collaboration, interactive pages, radio and television broadcasts, and
the automatic "push" of information to a client computer. Programming
languages such as Java, JavaScript, Visual Basic, Cold Fusion and XML
are extending the capabilities of the Web. A growing amount of
information on the Web is served dynamically from content stored in
databases. The Web is therefore not a fixed entity, but one that is in
a constant state of development and flux.
For more complete information about the World Wide Web, see Understanding The World Wide Web.
E-MAIL
Electronic
mail, or e-mail, allows computer users locally and worldwide to
exchange messages. Each user of e-mail has a mailbox address to which
messages are sent. Messages sent through e-mail can arrive within a
matter of seconds.
A powerful aspect of e-mail is the option to
send electronic files to a person's e-mail address. Non-ASCII files,
known as binary files, may be attached to e-mail messages. These files
are referred to as MIME attachments.MIME stands for Multimedia Internet
Mail Extension, and was developed to help e-mail software handle a
variety of file types. For example, a document created in Microsoft
Word can be attached to an e-mail message and retrieved by the
recipient with the appropriate e-mail program. Many e-mail programs,
including Eudora, Netscape Messenger, and Microsoft Outlook, offer the
ability to read files written in HTML, which is itself a MIME type.
TELNET
Telnet
is a program that allows you to log into computers on the Internet and
use online databases, library catalogs, chat services, and more. There
are no graphics in Telnet sessions, just text. To Telnet to a computer,
you must know its address. This can consist of words (locis.loc.gov) or
numbers (140.147.254.3). Some services require you to connect to a
specific port on the remote computer. In this case, type the port
number after the Internet address. Example: telnet nri.reston.va.us 185.
Telnet
is available on the World Wide Web. Probably the most common Web-based
resources available through Telnet have been library catalogs, though
most catalogs have since migrated to the Web. A link to a Telnet
resource may look like any other link, but it will launch a Telnet
session to make the connection. A Telnet program must be installed on
your local computer and configured to your Web browser in order to work.
With
the increasing popularity of the Web, Telnet has become less frequently
used as a means of access to information on the Internet.
FTP
FTP
stands for File Transfer Protocol. This is both a program and the
method used to transfer files between computers. Anonymous FTP is an
option that allows users to transfer files from thousands of host
computers on the Internet to their personal computer account. FTP sites
contain books, articles, software, games, images, sounds, multimedia,
course work, data sets, and more.
If your computer is directly
connected to the Internet via an Ethernet cable, you can use one of
several PC software programs, such as WS_FTP for Windows, to conduct a
file transfer.
FTP transfers can be performed on the World Wide
Web without the need for special software. In this case, the Web
browser will suffice. Whenever you download software from a Web site to
your local machine, you are using FTP. You can also retrieve FTP files
via search engines such as FtpFind, located at
/http://www.ftpfind.com/. This option is easiest because you do not
need to know FTP program commands.
E-MAIL DISCUSSION GROUPS
One
of the benefits of the Internet is the opportunity it offers to people
worldwide to communicate via e-mail. The Internet is home to a large
community of individuals who carry out active discussions organized
around topic-oriented forums distributed by e-mail. These are
administered by software programs. Probably the most common program is
the listserv.
A great variety of topics are covered by
listservs, many of them academic in nature. When you subscribe to a
listserv, messages from other subscribers are automatically sent to
your electronic mailbox. You subscribe to a listserv by sending an
e-mail message to a computer program called a listserver. Listservers
are located on computer networks throughout the world. This program
handles subscription information and distributes messages to and from
subscribers. You must have a e-mail account to participate in a
listserv discussion group. Visit Tile.net at /http://tile.net/ to see
an example of a site that offers a searchablecollection of e-mail
discussion groups.
Majordomo and Listproc are two other programs
that administer e-mail discussion groups. The commands for subscribing
to and managing your list memberships are similar to those of listserv.
USENET NEWS
Usenet
News is a global electronic bulletin board system in which millions of
computer users exchange information on a vast range of topics. The
major difference between Usenet News and e-mail discussion groups is
the fact that Usenet messages are stored on central computers, and
users must connect to these computers to read or download the messages
posted to these groups. This is distinct from e-mail distribution, in
which messages arrive in the electronic mailboxes of each list member.
Usenet
itself is a set of machines that exchanges messages, or articles, from
Usenet discussion forums, called newsgroups. Usenet administrators
control their own sites, and decide which (if any) newsgroups to
sponsor and which remote newsgroups to allow into the system.
There
are thousands of Usenet newsgroups in existence. While many are
academic in nature, numerous newsgroups are organized around
recreational topics. Much serious computer-related work takes place in
Usenet discussions. A small number of e-mail discussion groups also
exist as Usenet newsgroups.
The Usenet newsfeed can be read by a
variety of newsreader software programs. For example, the Netscape
suite comes with a newsreader program called Messenger. Newsreaders are
also available as standalone products.
FAQ, RFC, FYI
FAQ
stands for Frequently Asked Questions. These are periodic postings to
Usenet newsgroups that contain a wealth of information related to the
topic of the newsgroup. Many FAQs are quite extensive. FAQs are
available by subscribing to individual Usenet newsgroups. A Web-based
collection of FAQ resources has been collected by The Internet FAQ
Consortium and is available at /http://www.faqs.org/.
RFC stands
for Request for Comments. These are documents created by and
distributed to the Internet community to help define the nuts and bolts
of the Internet. They contain both technical specifications and general
information.
FYI stands for For Your Information. These notes are a subset of RFCs and contain information of interest to new Internet users.
Links
to indexes of all three of these information resources are available on
the University Libraries Web site at
/http://library.albany.edu/reference/faqs.html.
CHAT & INSTANT MESSENGING
Chat
programs allow users on the Internet to communicate with each other by
typing in real time. They are sometimes included as a feature of a Web
site, where users can log into the "chat room" to exchange comments and
information about the topics addressed on the site. Chat may take
other, more wide-ranging forms. For example, America Online is well
known for sponsoring a number of topical chat rooms.
Internet
Relay Chat (IRC) is a service through which participants can
communicate to each other on hundreds of channels. These channels are
usually based on specific topics. While many topics are frivolous,
substantive conversations are also taking place. To access IRC, you
must use an IRC software program.
A variation of chat is the
phenomenon of instant messenging. With instant messenging, a user on
the Web can contact another user currently logged in and type a
conversation. Most famous is America Online's Instant Messenger. ICQ,
MSN and Yahoo are other commonly-used chat programs.
Other types of real-time communication are addressed in the tutorial Understanding the World Wide Web.
MUD/MUSH/MOO/MUCK/DUM/MUSE
MUD
stands for Multi User Dimension. MUDs, and their variations listed
above, are multi-user virtual reality games based on simulated worlds.
Traditionally text based, graphical MUDs now exist. There are MUDs of
all kinds on the Internet, and many can be joined free of charge. For
more information, read one of the FAQs devoted to MUDs available at the
FAQ site at