What is the 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, although estimates are ongoing. It is certain, however, that these
number in the millions and are increasing at a rapid rate.
No one is in charge of the Internet. There are organizations which develop technical aspects of this network, 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 (your internet service provider) provides files and services to the user's local client
machine (your PC). Software can be installed on your PC to take advantage of the latest access technology.
Participation in and access to the Internet is primarily offered by these groups: research and educational
institutions; governmental and military entities; businesses; private organizations; and commercial providers.
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, and 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.
COMPONENTS OF THE INTERNET
WORLD WIDE WEB
The World Wide Web (abbreviated as the Web, WWW, or W3) 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, Gopher, 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.
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
World Wide 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 WWW 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. This page is written in 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 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, led by Web founder Tim
Berners-Lee, coordinates the efforts of standardizing HTML.
The World Wide Web consists of files, called pages or home pages, containing links to documents and resources
throughout the Internet. The University Libraries Home Page is located at http://www.albany.edu/library/.
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.
Newer programming languages such as Java and JavaScript are extending the capabilities of the Web.
On the University at Albany network, access to the Web is available on the IBM, UNIX, and VAX host
computers through a text-only software program called Lynx. The graphical browser Netscape Navigator is
available on public terminals in the University Libraries and in LC-15.
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 such as Pine. Many e-mail programs, including
Eudora and Netscape Messenger, offer the ability to read files written in HTML, which is itself a MIME type.
E-mail is available at the University at Albany on the IBM, UNIX, and VAX.
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. 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 University IBM, UNIX, and VAX host machines. Simply type the word telnet and then the
address.
Telnet is available on the World Wide Web. Probably the most common Web-based resources available through
Telnet are library catalogs. 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.
FTP
FTP stands for File Transfer Protocol. This is both a program and the method used to transfer files between
computers on the Internet. Anonymous FTP is an option that allows users to transfer files from thousands of
host computers on the Internet to their personal computer account. File transfer is quite rapid. FTP sites contain
books, articles, software, games, images, sounds, multimedia, course work, data sets, and more. On the University
network, FTP software is loaded into the IBM, UNIX, and VAX machines. Once the file has been transferred to
your computer account, you need to use a telecommunications program to transfer the file to your home PC.
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. You can retrieve TP files via search engines such as Snoopie, located at
http://www.snoopie.com/. This option is easiest because you do not need to know FTP program commands.
ARCHIE - THE SEARCH PROGRAM OF FTP
Archie functions as a catalog of FTP sites. Archie is a program that searches all the FTP sites on the Internet that
are on its master list, and stores the filenames in a central database. This database is available for users to search.
When you contact an Archie site and enter a search string, Archie searches the database and returns a list of all
files that contain that string. The list provides you with the address of the computer to contact and the directories
where the files are stored. Archie programs reside on the University's host computers.
As noted above, Archie search engines are also available on the Web. A collection of these services is available
at http://www.nexor.com/archie.html.
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 log into these computers to read
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. Newsreader software gives you
access to the newsgroup messages which are stored on a central computer at the University. Standard
newsreader software at Albany includes RN on UNIX. For example, to reach the RN newsreader on Unix from
your VAX account, simply type rn. Subscribing to and unsubscribing from newsgroups is a simple process that
takes effect immediately. For information on using the RN newsreader, see Using the RN Newsreader from the
VAX.
Newsreader programs are also available as standalone products, or are bundled with Web browsers. For example,
the Collabra newsreader program is available in the Netscape Communicator suite.
A list of available Usenet newsgroups can be accessed from within a newsreader program. Using the RN reader
on Unix, for example, you can type dir/group/all and receive a list of every newsgroup to which the University
subscribes.
FAQ
FAQ stands for Frequently Asked Questions. These are periodic postings to Usenet newsgroups that contain a
wealth of Internet and computer-related information. 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/.
&nbs;
IRC
IRC is the Internet Relay Chat service in which participants around the world can "talk" to each other by typing in
real time on hundreds of channels. These channels are usually based on a particular topic. While many topics are
frivolous, substantive conversations are also taking place. To have access to IRC, you must use an IRC software
program. This program connects you to an IRC server and allows you to visit IRC channels. At Albany, this
program is loaded on the VAX and UNIX host machines. For more information, read one of the FAQs about IRC
available at the FAQ site on the library home page.
Other types of real-time communication are addressed in the tutorial Understanding the World Wide Web.