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# HKCharacteristicTypeIdentifier

The identifiers that create characteristic type objects.

```
struct HKCharacteristicTypeIdentifier
```

## Overview

To create an [`HKCharacteristicType`](/documentation/HealthKit/HKCharacteristicType) instance, pass an [`HKCharacteristicTypeIdentifier`](/documentation/HealthKit/HKCharacteristicTypeIdentifier) value to the [`characteristicType(forIdentifier:)`](/documentation/HealthKit/HKObjectType/characteristicType(forIdentifier:)) method.

## Topics

### Characteristic Types

[`activityMoveMode`](/documentation/HealthKit/HKCharacteristicTypeIdentifier/activityMoveMode)

A characteristic identifier for the user’s activity mode.

[`biologicalSex`](/documentation/HealthKit/HKCharacteristicTypeIdentifier/biologicalSex)

A characteristic type identifier for the user’s sex.

[`bloodType`](/documentation/HealthKit/HKCharacteristicTypeIdentifier/bloodType)

A characteristic type identifier for the user’s blood type.

[`dateOfBirth`](/documentation/HealthKit/HKCharacteristicTypeIdentifier/dateOfBirth)

A characteristic type identifier for the user’s date of birth.

[`fitzpatrickSkinType`](/documentation/HealthKit/HKCharacteristicTypeIdentifier/fitzpatrickSkinType)

A characteristic type identifier for the user’s skin type.

[`wheelchairUse`](/documentation/HealthKit/HKCharacteristicTypeIdentifier/wheelchairUse)

A characteristic identifier for the user’s use of a wheelchair.

### Initializers

[`init(rawValue:)`](/documentation/HealthKit/HKCharacteristicTypeIdentifier/init(rawValue:))

Returns a newly initialized characteristic type identifier using the provided string.


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