Next on our disassembly line is the noticeably larger Taptic Engine.

The Taptic Engine is Apple's take on the linear resonant actuator. It creates motion in a straight line (as opposed to the circular motion of an electric motor), which in turn provides haptic feedback.

The concept of a linear resonant actuator isn't unique to Apple devices. Pancake-shaped LRAs have existed in electronic devices for years—but the choice to utilize a rectangular z-axis LRA provides Apple with more design freedom and more control over how the user perceives the vibration.