Learn in the textbookPointing and Manual Input Devices
DefinitionA touch panel (タッチパネル) is a device whose display doubles as the input surface, so the touched position on the screen becomes the input directly.
ExplanationBecause the display and the input device are one unit, you can directly select the buttons or pictures you see. Detection methods include the capacitive method, which reads changes in capacitance (the amount of stored charge) when a fingertip approaches, and the pressure-sensitive method, which reads where layered films touch when pressed. A pressure-sensitive panel responds to force, so it works even with gloves on.
AnalogyA board with elevator buttons drawn on it, where pressing the picture counts as pressing the real button.
Memory hook"Touch" means to make contact, and "panel" is a fitted board. Read it in two parts: a board you touch.