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# NSUserInterfaceItemIdentification

A set of methods used to associate a unique identifier with objects in your user interface.

```
protocol NSUserInterfaceItemIdentification
```

## Overview

The protocol is adopted by AppKit interface objects to support window restoration, whereby information about window and other interface-related objects is preserved and used to restore the application’s interface during the next launch cycle.

## Topics

### Accessing the User Interface Identifier

[`identifier`](/documentation/AppKit/NSUserInterfaceItemIdentification/identifier)

A string that identifies the user interface item.

[`NSUserInterfaceItemIdentifier`](/documentation/AppKit/NSUserInterfaceItemIdentifier)


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