text: is it possible that i can build a true or un true os in vb?   i would say no. vb depends too much on the operating system underneath it. with, say, a c compiler, you rewrite the c runtime library for your machine and you can do this because you've removed all the dependcies on the underlying os. but with vb you'd have to rewrite the entire vb run time which would require lots of reverse engineering and could not be done in vb itself!  now "untrue" os? you could write a "simulation" of an os in vb. sure. but it would be slow and would not be too useful. i've written simulators for microcontrollers in vb, which is similar. but that isn't really an os and really isn't very practical.  you might consider asking a more specific question about what you want to accomplish.