The key code has different meanings and interpretations, but basically it stands for key coding (code)!
Here one speaks simply of a code being assigned to a key, in short a number, mostly in computer science hexa numbers are used to represent them, although here they are basically binary numbers!
Example the house key is also a key code!
The lock manufacturer's code indicates which key opens the lock. The key code specifies which cracks and teeth should be used and how it should be cut, i.e. like a code-based key, this corresponds to the original factory specifications.
The overview of the keycodes under MS Windows for the keyboard!
Each key has a number assigned, which are also called keycode