If you want the visionary behind the Internet, it was J.C.R. Licklider. He envisioned an "Intergalactic Computer Network" in the early 1960s. He galvanized the

If you want the visionary behind the Internet, it was J.C.R. Licklider. He envisioned an "Intergalactic Computer Network" in the early 1960s. He galvanized the effort to start it, but wasn't the one to execute on it. The one to kickstart the effort was Larry Roberts, Lick's successor at the ARPA Information Processing Techniques Office (IPTO). It was Wesley Clark who suggested the use of a separate computer to do the packet switching for the network (as opposed to letting the host computer do it), the so called "Interface Message Processor", the equivalent of routers in today's Internet. In 1969 The ARPAnet was born with only two nodes, and from there started growing in the early 70s. The network protocol at the time was called NCP (Network Control Protocol), which handled both network layer and transport layer functionality. Vint Cerf and Bob Khan developed the "Transmission Control Program", which still did both layers, but later, towards the late 70s, revised it by separating the two into "Transmission Control Protocol" and "Internet Protocol", aka TCP/IP. The ARPAnet finally switched from NCP to TCP/IP on Jan 1, 1983, the so called birth of the Internet.