Source : Free On-Line Dictionary of Computing

global index
     
         (gid) The filename extension of a
        {Windows 95} "global index" file.  .gid files are created by
        the help {browser} internal to Windows 95 (also available for
        other Windows versions) for WinHelp files ({hlp}), as well as
        for storing user preferences, such as window position.
     
        (1997-01-30)