Learn in the textbookFundamentals of Interface Design and Input Operations
DefinitionGesture interface (ジェスチャーインタフェース) is an umbrella term for input methods that read body movements, such as those of the fingers or hands, and use them to operate a device.
ExplanationBesides tracing a finger across a screen, movements that never touch the screen, such as hand motions read by a camera or sensor, can also serve as input. Its strength is that people can operate devices much as they move in everyday life, without learning how to handle a keyboard or mouse.
AnalogyIt takes the body language you use without words, beckoning to say "come here" or holding up a palm to say "stop," and turns it into commands for a device.
Memory hookGesture means a movement of the body or hands. Placed before interface, it names a point of contact where you deal with a device through movement.