Defense Advanced Research Projects Agency (DARPA), U.S. government agency administered by the Department of Defense (see Defense, United States Department of). It was established in 1958, in reaction to the successful launch of Sputnik by the USSR, as the Advanced Research Projects Agency. Although DARPA is only one of many military agencies administering research and development funds, it has been crucial to the development of several important technologies, especially military computers and the Internet. It funds a high percentage of all artificial intelligence research in the United States, as well as significant projects in microelectronics, materials, and behavioral science.