The Internet began as the ARPANET during the cold war in 1969. It was developed by the U.S. Department of Defense's (DOD) research people together with a number of military contractors and universities to explore the possibility of a communications network that could survive during and after a nuclear attack. It provided such an easy way to communicate, that the DOD, its contractors, and the universities decided to continue using it.
The internet was used primarily for email, support on-line discussion groups, access distant databases, and to support the transfering of files between companies, government agencies, and universities. During the early 1980s, all the interconnected research networks were converted to the TCP/IP protocol , and the ARPANET became the 'physical' connection between the major sites of the new Internet, which comprised all TCP/IP-based networks connected to the ARPANET. By the end of 1983, the transition to TCP/IP was completed, and the Internet was born.
In 1990, HTML, a hypertext Internet protocol which could communicate the graphic information on the Internet, was introduced. It was now possible for individuals to create graphic pages (a Web site) of their own. These web pages then became a part of a huge, virtual hypertext network called the World Wide Web (WWW). The enhanced Internet was informally renamed the Web and a huge additional audience was created.
The term Internet refers to the physical structure of the Net, including client and server computers, and the phone lines that connect everything. The term web to refer to the collection of sites and the information that can be accessed when one is using the Internet.