In May 1974, the Institute of Electrical and Electronic Engineers (IEEE) published a paper titled "A Protocol for Packet Network Intercommunication." The authors which were Vint Cerf and Bob Kahn, described an internetworking protocol for sharing resources using packet-switching among the nodes.
A central control component for it was the Transmission Control Program (TCP) that incorporated both connection-oriented links and datagram between the hosts. The monolithic TCP was then divided into a modular architecture consisting of TCPs at the connection-oriented layer and the Internet Protocol at the datagram layer.
DCA and ARPA establish the Transmission Control Protocol (TCP) and Internet Protocol (IP), as the protocol suite. The model became known as TCP/IP for ARPANET.
The term was the one that first define the "internet" as a connected set of networks.