WIMP stands for:
W: Windows I: Icons M: Menus P: Pointing device
This is a term oftimes used to refer to the Graphical User Interface GUI interfaces commonly found on contemporary desktop systems.
If you're going to get into doing this sort of thing with Tcl, use Tk (or fltk, or ...) see Playing WIMP for a toy icon system.
See also: [L1 ] for "weakly interacting massive particles".