Animatronics involve robots or robotically controlled puppets, such as the dinosaurs in some films and TV shows. The dinosaur itself is a skin laid on top of an electronic control system with robotic limbs and triggers that control its programmed motion; it moves by manipulating its electronic controls. In some ways the principles are related to animation, in that it involves timing, sequencing motion, and assigning key points between motion A and motion B. Think of it as real-life animation with objects, though it's not to be confused with stop-motion animation. Stop-motion doesn't use electronics or robotics, so it doesn't qualify as animatronics.
In contrast, typical animations are either 2D drawings or 3D images captured on camera. The animated objects and motion are wholly created by the animator, rather than generated by real-life actions. For comparison: most the larger dinosaurs in the Jurassic Park film franchise are 3D animated. The actors aren't really interacting with them and can't touch them; they're added in later. The dinosaurs in the Jurassic Park roller coaster rides at Universal Studios are animatronic; they move, but you can touch them and interact with them.

