---
title: Data Types
framework: kernel
role: collectionGroup
role_heading: API Collection
path: kernel/libkern/data_types
---

# Data Types

Create strings, numbers, collections, data objects, and the other standard types employed by drivers and kernel extensions.

## Topics

### Simple Types

- [OSBoolean](kernel/osboolean.md)
- [OSString](kernel/osstring.md)
- [OSNumber](kernel/osnumber.md)
- [OSData](kernel/osdata.md)

### Collections

- [OSArray](kernel/osarray.md)
- [OSDictionary](kernel/osdictionary.md)
- [OSSet](kernel/osset.md)
- [OSOrderedSet](kernel/osorderedset.md)
- [OSCollection](kernel/oscollection.md)
- [OSCollectionIterator](kernel/oscollectioniterator.md)
- [OSIterator](kernel/ositerator.md)

### Signed Integers

- [LittleSInt16](kernel/littlesint16.md)
- [LittleSInt32](kernel/littlesint32.md)
- [LittleSInt64](kernel/littlesint64.md)
- [BigSInt16](kernel/bigsint16.md)
- [BigSInt32](kernel/bigsint32.md)
- [BigSInt64](kernel/bigsint64.md)

### Unsigned Integers

- [LittleUInt16](kernel/littleuint16.md)
- [LittleUInt32](kernel/littleuint32.md)
- [LittleUInt64](kernel/littleuint64.md)
- [BigUInt16](kernel/biguint16.md)
- [BigUInt32](kernel/biguint32.md)
- [BigUInt64](kernel/biguint64.md)
- [U128](kernel/u128.md)

### Actions

- [OSAction](kernel/osaction.md)
- [OSActionInterface](kernel/osactioninterface.md)

### Callback Methods

- [OSActionAbortedHandler](kernel/osactionabortedhandler.md)
- [OSActionCancelHandler](kernel/osactioncancelhandler.md)
- [OSDispatchMethod](kernel/osdispatchmethod.md)
- [OSKextRequestResourceCallback](kernel/oskextrequestresourcecallback.md)
- [OSObjectApplierFunction](kernel/osobjectapplierfunction.md)
- [OSSerializerBlock](kernel/osserializerblock.md)
- [OSSerializerCallback](kernel/osserializercallback.md)

### Serialization

- [OSSerialize](kernel/osserialize.md)
- [OSSerializer](kernel/osserializer.md)

### Base Types

- [OSSymbol](kernel/ossymbol.md)
- [OSObject](kernel/osobject.md)
- [OSMetaClass](kernel/osmetaclass.md)
- [OSMetaClassBase](kernel/osmetaclassbase.md)
- [OSObjectPtr](kernel/osobjectptr.md)
- [OSObjectRef](kernel/osobjectref.md)
- [Additional Types](kernel/libkern/data_types/additional_types.md)

## See Also

### Resources

- [Memory](kernel/iokit_fundamentals/memory.md)
- [Workflow and Control](kernel/iokit_fundamentals/workflow_and_control.md)
- [Locks](kernel/iokit_fundamentals/locks.md)