Finally, there is feedback, probably the most important part of a game mechanic in video games.
Wikipedia gives the following definition of video games:
"A video game is an electronic game that involves interaction with a user interface to generate visual feedback on a video device".
The word feedback is part of the very definition of video games.
We could argue that the Wikipedia definition is not complete (or up to date), as that feedback is not necessarily visual. It can well be audio or even haptic (the most traditional haptic feedback is the vibration of a console controller, but haptic feedback and devices are evolving at an incredible pace with the growth of virtual reality).
Feedback is everywhere ...
