This first one is extremely low-tech but effective for its day. A series of magazine pictures shot frame by frame with a super-8 movie camera. Wipes were accomplished by slicing the page away with a razor frame by frame. It was later transferred to video for a training tape.
The snake charmer was a series of drawings then page-flipped.
The frog was drawn on paper and dropped into PhotoShop where a plane was added.
The letter "C" morphs into a hand drawn cat, animated page-flip style.