The Internet

The Internet has been describe in many ways.  Some think of it as a highway while others think of it as a great marketplace.  Most of the metaphors that people use don't quite paint a clear picture, but do at least incite the imagination toward its applications.  It is largely used to "ship" data around the world, like a highway of sorts, and it has become a resource through which every conceivable product may be purchased, like a marketplace.  Technically the Internet is a network of networks all sharing a common protocol and naming schema.  But since it opens up so many possibilities for telecommunications, it may be thought of as a community.  Interestingly, the way it is used today is a far cry from its intended purpose.

The U.S. Department of Defense laid the foundation of the Internet roughly 30 years ago with a network called ARPANET. But the general public didn't use the Internet much until after the development of the World Wide Web in the early 1990s. As recently as June 1993, there were only 130 Web sites. Now there are millions. Here's a quick look at how it all came to be.

In 1957, the United States government formed the Advanced Research Projects Agency (ARPA), a segment of the Department of Defense charged with ensuring U.S. leadership in science and technology with military applications. Just more than a decade later, in 1969, ARPA established ARPANET, the forerunner of the Internet.

Research and education

ARPANET was a network that connected major computers at the University of California at Los Angeles, the University of California at Santa Barbara, Stanford Research Institute, and the University of Utah. Within a couple of years, several other educational and research institutions joined the network.

In response to the threat of nuclear attack, ARPANET was designed to allow continued communication if one or more sites were destroyed. Unlike today, when millions of people have access to the Internet from home, work, or their public library, ARPANET served only computer professionals, engineers, and scientists who knew their way around its complex workings.

Evolution

Throughout the 1970s, developers created the protocols used to transfer information over the Internet. By the early 1980s, Usenet newsgroups and electronic mail had been born. Most users ere affiliated with universities, although libraries began to connect their catalogs to the Internet, too. During the late 1980s, developers created indices, such as Archie and Wide Area Information Server (WAIS), to keep track of the information on the Internet. To give users a friendly, easy-to-use interface to work with, the University of Minnesota created its Gopher, a simple menu system for accessing files, in 1991.

The World Wide Web came into being in 1991, thanks to developer Tim Berners-Lee and others at the European Laboratory for Particle Physics, also known as Conseil Européenne pour la Recherche Nucléaire (CERN). The CERN team created the protocol based on hypertext that makes it possible to connect content on the Web with hyperlinks. Berners-Lee now directs the World Wide Web Consortium (W3C), a group of industry and university representatives that oversees the standards of Web technology.

Early on, the Internet was limited to noncommercial uses because its backbone was provided largely by the National Science Foundation, the National Aeronautics and Space Administration, and the U.S. Department of Energy, and funding came from the government. But as independent networks began to spring up, users could access commercial Web sites without using the government-funded network. By the end of 1992, the first commercial online service provider, Delphi, offered full Internet access to its subscribers, and several other providers followed.

In June 1993, the Web boasted just 130 sites. By a year later, the number had risen to nearly 3,000. As of April 1998, there were more than 2.2 million sites on the Web.

Who's in control here?

No one authority controls the World Wide Web. Today's Web site authoring tools allow virtually anyone who has access to a computer and the Internet to post a Web site and contribute to the definition of what this medium is and what it can do. But the World Wide Web Consortium (W3C) does oversee the development of Web technology.

You shape the Web

According to the developer of the World Wide Web, Tim Berners-Lee, "The dream behind the Web is of a common information space in which we communicate by sharing information. Its universality is essential: the fact that a hypertext link can point to anything, be it personal, local, or global, be it draft or highly polished."

With the development of tools that allow us to create Web sites without having any knowledge of hypertext markup language (HTML), this dream is being realized. If you read the "Creating a Web Site" chapter, you can be one of the forces shaping this "common information space."

World Wide Web Consortium

Keeping an eye on the standards of Web technology is W3C, formed by Berners-Lee in 1994. An international group of industry and university representatives, W3C promotes the Web by developing common protocols for transmitting information over the Internet. The consortium provides information, reference code, and prototype and sample applications to developers and users. It is hosted by the Massachusetts Institute of Technology's Laboratory for Computer Science in the United States, the Institut National de Recherche en Informatique et en Automatique in Europe, and the Keio University Shonan Fujisawa Campus in Japan.

How do computer connect on the Internet?

Internet computers recognize one another because each is assigned a special number: an IP Address. An IP address is 32 bits (4 bytes) wide and may be represented various ways.

IP Address in Binary 11000000 01100110 11111001 00000011
Same in Decimal 3,227,973,891
Same in Hexadecimal 0xC066F903
Same in Dotted-quad 192.102.249.3

All IP address must be unique, hence, all Internet network ID numbers are managed by a single entity - the Internet Network Information Center (InterNIC).  As shown below, organizations both large and small can tap into the Internet and identify each computer by "name" (IP Address).

A connection is made by requesting acknowlegement by a particular IP Address.  Messages will be redirected and routed along the best available path to travel from source to destination.  Technically the system works very well, but for people, attempting to memorize large numbers is tedious at best.  As a solution, the Domain Name System was developed.

What are domains?

Domains divide World Wide Web sites into categories based on the nature of their owner, and they form part of a site's address, or uniform resource locator (URL). Common top-level domains are:

• .com-For commercial enterprises.
• .org-For nonprofit organizations.
• .net-For networks.
• .edu-For educational institutions.
• .gov-For government organizations.
• .mil-For military services.
• .int-For organizations established by international treaty.

Additional three-letter and four-letter top-level domains have been proposed, and some are likely to be implemented. Each country linked to the Web has a two-letter top-level domain.