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# CGKeyCode

Represents the virtual key codes used in keyboard events.

```
typealias CGKeyCode = UInt16
```

## Discussion

In macOS, the hardware scan codes generated by keyboards are mapped to a set of virtual key codes that are hardware-independent. Pressing a given key always generates the same virtual key code on any supported keyboard.

As keys are pressed, the system uses the virtual key codes to create low-level keyboard events. For information on how to simulate a keyboard event, see the function [`init(keyboardEventSource:virtualKey:keyDown:)`](/documentation/CoreGraphics/CGEvent/init(keyboardEventSource:virtualKey:keyDown:)).

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