Please kindly watch on YouTube!
https://www.youtube.com/watch?v=EDEP5pXAgkM
A touchscreen is one of Human-Machine Interface. It is an input device and normally layered on the top of an electronic visual display of an information processing system.
A user can give input or control the information processing system through simple or multi-touch gestures by touching the screen with a special stylus or one or more fingers.
The touchscreen enables the user to interact directly with what is displayed, rather than using a mouse, keyboard, or other such.