Source : Free On-Line Dictionary of Computing

El Camino Bignum
     
         /el' k*-mee'noh big'nuhm/ The road mundanely called
        El Camino Real, a road through the San Francisco peninsula
        that originally extended all the way down to Mexico City and
        many portions of which are still intact.  Navigation on the
        San Francisco peninsula is usually done relative to El Camino
        Real, which defines {logical} north and south even though it
        isn't really north-south many places.  El Camino Real runs
        right past {Stanford University}.
     
        The Spanish word "real" (which has two syllables: /ray-al'/)
        means "royal"; El Camino Real is "the royal road".  In the
        {Fortran} language, a "{real}" quantity is a number typically
        precise to seven significant digits, and a "{double
        precision}" quantity is a larger {floating-point} number,
        precise to perhaps fourteen significant digits (other
        languages have similar "real" types).
     
        When a {hacker} from {MIT} visited Stanford in 1976, he
        remarked what a long road El Camino Real was.  Making a pun on
        "real", he started calling it "El Camino Double Precision" -
        but when the hacker was told that the road was hundreds of
        miles long, he renamed it "El Camino Bignum", and that name
        has stuck.  (See {bignum}).
     
        [{Jargon File}]
     
        (1996-07-16)