When I was a child, sometimes I picked my notebook and draw something near the edge of the sheet. Then I drawed the same object on 10 or even 20 sheets but with some changes, maybe with different position or rotation or this object could transformed to Hulk, I don’t know – I was a child. Then I leafed sheets and I got my first animations. I think most of people made it in their childhood.
Today I prepared an After Effects tutorial about leafing animation.
After Effects template here: Sheet leafing animation