If I'm correct in my recalling of this subject an automag is a mag that is electronic. Which means that it runs off of batteries that you charge or that you can purchase at your local "S" mart.
They are usually much faster than the mech trigger markers or also dubbed "regular mags" because there is a trigger difference. Which you can probably guess as of now.
Automags have LCD computers in them. At least from what I remember they do. That makes them adjustable on the way we want them to shoot. Whearabout you could have a diagram such as this:
1. Semi Auto
2. 3-5 burst
3. Full Auto
So it goes into subdivisions like that. But even in semi auto those things are pretty quick. So that's the meaning of automags and what their differences are.
You can find out more about Automags and regular mags at:
www.airgun.com
I hope I helped you solve your question.