The first network was called ARPANET because the initial work was funded by an agency of the U.S. Department of Defense called the Advanced Research Projects Agency (ARPA).
The Department of Defense had two major goals for the initial project. The first goal, which was drivent by national sercurity concers, was to devlop the hardware and software needed to create a geographicall dispersed network that could function even if part of the network was disabled or destroyed. The second goal was to create a way for scientists at different locations to share information and collaborate on military and scientific projects.
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