Source : Free On-Line Dictionary of Computing

Advanced Research Projects Agency Network
     
         (ARPANET) A pioneering longhaul {wide area
        network} funded by {DARPA} (when it was still called "ARPA"?).
        It became operational in 1968 and served as the basis for
        early networking research, as well as a central {backbone}
        during the development of the {Internet}.  The ARPANET
        consisted of individual {packet switching} computers
        interconnected by {leased lines}.  {Protocols} used include
        {FTP} and {telnet}.  It has now been replaced by {NSFnet}.
     
        [1968 or 1969?]
     
        (1994-11-17)