If, at the DOS prompt, you type PERM, the following information appears:

=========================================================================

PERM -- Build decision trees
(C) MaxThink 1987   44 Rincon,  Kensington, CA  94707   (415) 428-0104
Input           Attribute file   (i.e., price with subtopic categories)
Input           Item      file   (i.e., filename with subtopic categories)
Input           Order     file   (i.e., market with subtopics categories)
Output          decision trees in MaxThink format
usage:          perm  attrifile  itemfile  setfile  outfile

=========================================================================

Comment:
        Without becoming too complex, PERM will automatically build
        expert-level rules for advice in one node from another.

        The PERM program:

        - links information components of a file to the file <PERMA>
        - links information components to information categories <PERMB>
        - links information categories to needs of various users  <PERMC>
        - outputs minimum-path hierarchies to each file for each user <PERMD>