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Chapter 4, Getting Online
Page 32
Overview of the Internet
The term internet literally means “network of networks”. The Internet is a global
network connecting millions of computers. It has more than 100 million users
worldwide, and that number continues to grow every day. More than 100 countries
are linked together through exchanges of data, news, and opinions.
Internet History
The Internet was originally known as the ARPANET and was developed by the US
Department of Defense (DOD) during the cold war in 1969. At that time, the DOD
arranged with a number of military contractors and universities to see whether a
communications network could be devised that would survive a nuclear attack.
For the first decade of its existence, the ARPANET was primarily used to facilitate
e-mail, support online discussion groups, allow access to distant databases, and
support file transfers between government agencies, universities, and a small
number of businesses.
During the early 1980s, the interconnected research networks converted to the
TCP/IP protocol, which provided a communications standard that enables different
types of computers to communicate with each other. Once there was a common
method for computer to “talk” to on another, the Internet started to grow.
In 1990, HTML (hypertext markup language) was developed for creating Web
pages that included both text and graphics as well as links from one place to
another. Using HTML, individuals could create pages for display on the Internet
that contained colored text of different sizes and shapes as well as pictures and
drawings. Some pages contained links to other parts of the document or to other
pages on the Internet. These sites formed the now huge, virtual hypertext network
called the World Wide Web (WWW). The World Wide Web forms a major portion
of the Internet and serves a huge audience.
Over the years, a number of different services have developed to encourage
information sharing between Internet sites. Because the Internet was originally
research-oriented, many of the early services were hard to use and poorly
documented. Now that the Internet has expanded to commercial and private sites,
however, new services with friendly interfaces have developed that make the
Internet easier to use and make it easy to create new Internet sites.