Source : Free On-Line Dictionary of Computing

Internet Worm
     
         The November 1988 {worm} perpetrated by
        {Robert T. Morris}.  The worm was a program which took
        advantage of bugs in the {Sun} {Unix} {sendmail} program,
        {Vax} programs, and other security loopholes to distribute
        itself to over 6000 computers on the {Internet}.  The worm
        itself had a bug which made it create many copies of itself on
        machines it infected, which quickly used up all available
        processor time on those systems.
     
        Some call it "The Great Worm" in a play on Tolkien (compare
        {elvish}, {elder days}).  In the fantasy history of his Middle
        Earth books, there were dragons powerful enough to lay waste
        to entire regions; two of these (Scatha and Glaurung) were
        known as "the Great Worms".  This usage expresses the
        connotation that the RTM hack was a sort of devastating
        watershed event in hackish history; certainly it did more to
        make non-hackers nervous about the Internet than anything
        before or since.
     
        (1995-01-12)