The very idea of the Internet has been authored by Leonard Kleinrock in his first paper entitled "Information Flow in Large Communication Nets," published May 31, 1961. In 1962, he developed packet switching.
The idea of the network that later became "ARPANET" was developed by L. Kleinrock, J. Licklider and R. Taylor.
In the further initial creation, the following individuals took essential part:
Elmer Shapiro from the Stanford Research Institute (SRI), Steve Carr, Steve Crocker, Jeff Rulifson, Ron Stoughton, Paul Baran, Thomas Marill, Lawrence Roberts, Barry Wessler, Bolt Beranek.
The very first message has been distributed by Kleinrock's student Charley S. Kline on October 29, 1969, from UCLA laboratory to Stanford University.