The Analyze/RMS_File utility imposes a hierarchical tree
    structure on top of the internal RMS file structure. This tree
    structure allows you to easily wander around in the RMS file
    and inspect the various data structures. Each data structure in
    the file represents a node in the tree, with a branch for each
    pointer in the structure.

    The interactive mode of the Analyze/RMS_File utility maintains
    an item called the "structure pointer". The commands allow you
    to move this pointer through the tree structure and examine the
    file.