In this two-part article, I trace the history of the Internet.The Internet started in 1969 as an experiment by the AdvancedResearch Projects Agency (ARPA) of the US Departmentof Defense to use packet switching on leased telephonelines to connect four mainframe computers. Email was inventedin 1971 and it became a “killer application” as it promotedeasy interaction among its users. By 1972, fifty computerswere connected using leased telephone lines to formwhat was known as the ARPANET which was successfullydemonstrated at an international conference – ICCC 72.ARPANET was followed by Packet Radio Network (PRNET),which connected mobile computers, and Satellite Network(SATNET), which connected computers in Europe with thosein the US. A protocol named Transmission Control Protocol/Internet Protocol (TCP/IP) was invented in 1973 to interconnectARPANET,PRNET, and SATNET. The success of theTCP/IP protocol in connecting disparate networks paved theway for the development of the Internet.

In this part, I describe how CSNET started in 1981with funding from the National Science Foundation (NSF) of the USgovernment and the formation of the Merit network and BIT-NET. Following this, I discuss the formation of the NSFnet in1986 connecting the supercomputer centres set up by the NSFin the US and its expansion by connecting it to the ARPANET,CSNET, Merit, and regional networks. I then trace the steadyimprovement of the speed of the NSF net and its gradualprivatization and the emergence of the worldwide Internet.I then describe the evolution of the Domain Name Systemand the consequences of the rapid expansion of the Internet.The article concludes with issues of governance of the Inter-net which has now become an essential infrastructure of ourWorld.