What is the difference between Vno and Va What is the difference between the maximum structural cruising speed (Vno) and the manuevering speed (Va)?  Can you also please explain how these speeds are calculated?

I do understand that Va is set to where the wing will stall before the plane will go over its G limit but what does Vno mean?
Va limits G loads resulting from pilot input of maximum control deflection to limit load.  Vno limits G loads caused by vertical gusts over 30 ft/sec, without pilot input, to limit load.   

In other words, Va protects you from bending the wings from pulling too hard, and Vno protects you from bending the wings from going too fast through bumps.