No one person or organization can claim the sole credit for the Internet.
But the first germ of the Internet was a series of memos written in 1962 by MIT's J. C. R. Licklider about what he called the "Galactic Network" concept. He envisioned a global network through which everyone could share and access data and programs. Only a few months later, Licklider became the head of the computer research program at the United States Department of Defense's Advanced Research Projects Agency (ARPA), the institution that largely funded the Internet's development.
In 1961, a series of independent research teams began developing packet switching and the beginnings of what would eventually become TCP/IP, the basic protocol that defines how information is exchanged over the Net. In 1967, ARPA's Lawrence Roberts published his "Plan for the ARPANet" computer network, which built on these new technologies to propose an architectural design for a worldwide network.
By the end of 1968, the company that would become BBN Planet (a major backbone ISP recently bought by GTE) was well into the development of the first hardware that could route data over the ARPANet. In late 1969, the first tests were made at UCLA and then at Stanford.
Over the next several years, this orginal Internet grew steadily but unremarkably as government agencies, universities, and corporations continued to develop and hammer out protocols and architectures. E-mail and the Internet made their first public appearances in 1972 at the Internet Computer Communication Conference. In 1973 and 1974, the protocol known as TCP/IP emerged in essentially its current form, although the same group of collaborators would continue to refine it through the early 1980s.
Once the protocols were in place, the various developers created much of the software and services that make up the Internet. The basic services for connecting to files remotely (via Telnet), transferring files over the Net (via FTP), and sending and receiving electronic mail appeared in the mid- and late 1970s. The Usenet news system first came to be in 1979 as an offshoot of the rise of Unix. The World Wide Web began in 1989.
In 1990, the U.S. government officially decommissioned ARPANet, and the National Science Foundation took over the role of managing the Internet backbone, which was then called the NSFNet. In 1995, the NSF in turn withdrew, turning the backbone over to commercial providers.