---
title: "<unordered_map>"
description: "API overview for the C++ Standard Library container class `map`."
ms.date: "11/04/2016"
f1_keywords: ["<unordered_map>"]
helpviewer_keywords: ["unordered_map header"]
ms.assetid: eb90ecb2-250a-4be1-83d2-f66b2917edde
---
# `<unordered_map>`

Defines the container class templates [unordered_map](../standard-library/unordered-map-class.md) and [unordered_multimap](../standard-library/unordered-multimap-class.md) and their supporting templates.

## Syntax

```cpp
#include <unordered_map>
```

> [!NOTE]
> The \<unordered_map> library also uses the `#include <initializer_list>` statement.

### Classes

|Class|Description|
|-|-|
|[unordered_map Class](../standard-library/unordered-map-class.md)|Stores hash table of {key, mapped} pairs.|
|[unordered_multimap Class](../standard-library/unordered-multimap-class.md)|Stores hash table of {key, mapped} pairs.|

### Functions

|Function|Description|
|-|-|
|[operator!=](../standard-library/unordered-map-operators.md#op_neq)|Tests if the unordered_map object on the left side of the operator is not equal to the unordered_map object on the right side.|
|[operator==](../standard-library/unordered-map-operators.md#op_eq_eq)|Tests if the unordered_map object on the left side of the operator is equal to the unordered_map object on the right side.|
|[swap Function (unordered_map)](../standard-library/unordered-map-functions.md#swap)|Swaps two maps.|
|[operator!=](../standard-library/unordered-map-operators.md#op_neq)|Tests if the unordered_multimap object on the left side of the operator is not equal to the unordered_multimap object on the right side.|
|[operator==](../standard-library/unordered-map-operators.md#op_eq_eq)|Tests if the unordered_multimap object on the left side of the operator is equal to the unordered_multimap object on the right side.|
|[swap Function (unordered_map)](../standard-library/unordered-map-functions.md#swap)|Swaps two multimaps.|

## See also

[unordered_multiset Class](../standard-library/unordered-multiset-class.md)\
[unordered_set Class](../standard-library/unordered-set-class.md)