> an OS (real time or not) > > a Graphical User interface (basically make my own windows for > example). What do you mean by these terms? Is it an OS if it simply schedules tasks? Or do you use MS's definition, which includes most of the guts of an internet browser? By GUI, do you mean a library of routines that do things like drawing multi-font text or rectangles on the screen? Or does it have to support floating menus, tooltips, etc etc?