Internet

The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite (often called TCP/IP, although not all applications use TCP) to serve billions of users worldwide. In short, it is an interconnection of networks scattered all over the globe by means of exchanging information worldwide.

Any two computers, often having different software and hardware, can exchange information over the Internet, as long as they obey the technical rules of Internet communication. The exchange of information may be among connected computers located anywhere, like military and research institutions, different kinds of organizations, banks, educational institutions (elementary schools, high schools, colleges), public libraries, commercial sectors, etc.

History of  the Internet

It has evolved from a research prototype project to a full-grown commercial computer communication system. The growth can be discussed in three steps, as follows:

1. Internetworking Protocol—Transmission Control Protocol/Internet Protocol (TCP/IP) in 1970s
2. Usenet groups and Electronic mail in 1980s
3. World Wide Web in 1990s

• The history begins with electronic computers in the 1950s. Initial concepts of packet networking originated in several computer science laboratories in the United States, United Kingdom, and France. The US Department of Defense awarded contracts as early as the 1960s for packet network systems, including the development of the ARPANET. The first message was sent over the ARPANET from computer science Professor Leonard Kleinrock Laboratory at the University of California, Los Angeles (UCLA) to the second network at Stanford Research Institute (SRI).
• Packet switching networks such as ARPANET, NPL NETWORK, TELNET were developed in the late 1960s and early 1970 using a variety of communications protocols.
• In short, it has roots in the ARPANET system of ARPA of the U.S. Department of Defense. ARPANET was the first WAN & had only four sites in 1969.

Intranet

An intranet is a computer network that uses Internet Protocol technology to share information, operational systems, or computing services within an organization. The term is used in contrast to the internet, a network between organizations, and instead refers to a network within an organization. The objective is to organize each individual’s desktop with minimal cost, time, and effort to be more productive, cost-efficient, timely, and competitive.