Source : Free On-Line Dictionary of Computing

Maker Interchange Format
     
        (MIF) A language used to describe a {FrameMaker} document in a
        text file.  MIF is used to exchange information between
        FrameMaker and other applications.
     
        ["Using FrameMaker 4," Windows and Macintosh Version,
        c. 1986-1993 Frame Technology Corporation].
     
        (1995-01-30)