ARPANET—The Birth of the Internet
Before people could interact through computer networks, they had to be able to interact with computers. The first step was to develop computers that could "time-share"—switch quickly from program to program and user to user. The next step was to find a way for one computer to "talk" to another. The Department of Defense's Advanced Research Projects Agency (ARPA) sponsored research that made both steps possible. The world's first large-scale computer network, the ARPANET, became operational in 1969.