Jesus...did you read it ALL? There are THREE types. They lay them out.
My point is it's not just me that knows the difference. If you don't know it or won't admit to it that isn't my problem.
They operate on two entirely different systems. One system opens the throttle blades and the other opens an air valve. One has mechanical secondary throttle blades, the other has vacuum operated throttle blades.
There is a HUGE difference.
Edit: forgot to mention the comparison to a choke plate, which is what I suspect is happening. Can't have that with a vacuum secondary carb.