---
title: typeIdentifier
framework: appkit
role: symbol
role_heading: Type Property
path: appkit/nsfontdescriptor/featurekey/typeidentifier
---

# typeIdentifier

A key that indicates the type of the font feature.

## Declaration

```swift
static let typeIdentifier: NSFontDescriptor.FeatureKey
```

## Discussion

Discussion The value of this key is an NSNumber object specifying a font feature type such as ligature, character shape, and so on. For more information on Apple Fonts see Fonts for Apple platforms and the AAT Font Feature Registry.

## See Also

### Feature Keys

- [selectorIdentifier](appkit/nsfontdescriptor/featurekey/selectoridentifier.md)