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# uniqueID

The unique identifier of the pointing device that generated this event.

```
var uniqueID: UInt64 { get }
```

## Discussion

Also known as tool ID, this is a unique number recorded in the chip inside every pointing device. The unique ID makes it possible to assign a specific pointing device to a specific tablet. You can also use it to “sign” documents or to restrict access to document layers to a specific pointing device. This method is valid for mouse events with subtype `NSTabletProximityEventSubtype` and for `NSTabletProximity` events.

## See Also

[`vendorDefined`](/documentation/AppKit/NSEvent/vendorDefined)

An array of three vendor-defined number objects associated with a pointing-type event.


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