Answer:
ARPANET
Step-by-step explanation:
ARPANET has been the network which became the backbone of the Internet.
ARPANET was established under the guidance of the US based on a definition first published in 1967. An Agency for Advanced Research Projects (ARPA).
With the interconnection of four university computers the idea became a practical fact in 1969. At the connected institutions, the initial aim was to communicate with and share computer resources mainly among scientific users.
ARPANET took advantage of the revolutionary concept of sending information in small units called packets that could be routed and retrieved at their destination on various routes.
The introduction of the TCP / IP protocols in the 1970s allowed organized expansion of the size of the network, which had now become a network of networks.