---
title: UInt128.Words
framework: swift
role: symbol
role_heading: Structure
path: swift/uint128/words-swift.struct
---

# UInt128.Words

A type that represents the words of a binary integer.

## Declaration

```swift
@frozen struct Words
```

## Overview

Overview The Words type must conform to the RandomAccessCollection protocol with an Element type of UInt and Index type of Int.

## Topics

### Default Implementations

- [BidirectionalCollection Implementations](swift/uint128/words-swift.struct/bidirectionalcollection-implementations.md)
- [Collection Implementations](swift/uint128/words-swift.struct/collection-implementations.md)
- [RandomAccessCollection Implementations](swift/uint128/words-swift.struct/randomaccesscollection-implementations.md)
- [Sequence Implementations](swift/uint128/words-swift.struct/sequence-implementations.md)

## Relationships

### Conforms To

- [BidirectionalCollection](swift/bidirectionalcollection.md)
- [BitwiseCopyable](swift/bitwisecopyable.md)
- [Collection](swift/collection.md)
- [Copyable](swift/copyable.md)
- [Escapable](swift/escapable.md)
- [RandomAccessCollection](swift/randomaccesscollection.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)
- [Sequence](swift/sequence.md)