I am an amateur programmer, and I have a couple of questions about ZShell programming. 1) What in the world is VAT? 2) I know about registers and that kind of stuff, but what is the function of IX,IY,and AF? 3) I know that there are many different TI-85 shells, but which one is the best? and finally 4) What in the world is Supernova (not the star :-) )? Thanx