Created during a project funded by Defense Advanced Research Projects Agency in 1969. Network was called ARPANET.
It is said that a primary goal of this advanced network was to allow communications to continue in the event of nuclear strikes upon the United States. Therefore, the network had to be redundant and offer multiple communication paths.
In 1975 ARPANET was converted from an experimental network to an operational network.
The basic TCP/IP protocols were developed after ARPANET was operational.
TCP/IP protocols were adopted as Military Standards in 1983, and all hosts connected to the network were required to convert to the new protocols. To ease the conversion, DARPA funded a project to implement TCP/IP into UNIX.
The term Internet came into usage about this same time.
For many years, universities and government-related businesses used the Internet for e-mail, newsgroups, and file transfers between sites.
In 1990 ARPANET formally passed out of existence. A new backbone named NSFNET was funded by the National Science Foundation.
