Vr6 Auto Box

[Justice]

I have been looking through the Haynes book on the Galaxy (even though I have a VR6 Sharan) and thought I would check how to top up my auto transmision fluid,the book says it is best to take it to a dealer as they will plug in the diagnostic to make sure it is at the right temp for checking so for me to do this would be hit or miss as to weather I got it right , then on the very next page it says about topping up the final drive level which is a different fluid but still for an auto box.

I am not stupid but could someone explain what and why there are to different oils in the auto box,becouse in olden days an auto box just had auto fluid.