Source : Free On-Line Dictionary of Computing

Didot point
     
         A variant of the {point}, equal to 0.3759 mm, or
        1/72 of a French Royal inch (27.07 mm), or about 1/68 inch.
        Didot points are used in Europe.  This unit is named after the
        French printer Francois Ambroise Didot (1730 - 1804) who
        defined the "point-based" typographical measurement system.
     
        (2002-03-11)