Haptics
Haptics, also called haptic technology, are mechanisms that produce small vibrations that help an electronic device provide tactile feedback. Smartphones, wearable devices, video game controllers, and laptop touchpads often contain haptic technology. It can create the illusion that a device is reacting to your touch or even pushing back against it.
Many devices use haptics to simulate clicks and taps when you interact with a touchscreen, touchpad, or other input device. For example, when you type on a smartphone's on-screen keyboard, it may slightly vibrate every time you tap a letter. This tactile feedback simulates the feeling of pressing a real key and lets you know that the smartphone recognized your input. Haptic feedback is also used for silent notifications, especially on smartwatches — notifying you of a new message by quietly tapping your wrist instead of playing a sound.
Early forms of haptic feedback were present in video game controllers, like the Nintendo 64's optional Rumble Pak or the Sony PlayStation's DualShock controller. These early technologies, often called "force feedback," created vibrations by rapidly spinning an unbalanced weight. These controllers were bulky and could only provide a rough rumble effect. Modern haptics instead produce vibrations using small electromagnetic coils and spring-loaded weights. These coils are significantly smaller and can create far more precise movements than spinning weights.