# @ohos.app.ability.ExtensionAbility (ExtensionAbility Base Class)
<!--Kit: Ability Kit-->
<!--Subsystem: Ability-->
<!--Owner: @yewei0794-->
<!--Designer: @jsjzju-->
<!--Tester: @lixueqing513-->
<!--Adviser: @huipeizi-->

<!--Kit: Ability Kit-->
<!--Subsystem: Ability-->
<!--Owner: @yewei0794-->
<!--Designer: @jsjzju-->
<!--Tester: @lixueqing513-->

ExtensionAbility is the base class for scenario-specific ExtensionAbilities. It inherits from [Ability](js-apis-app-ability-ability.md), with no property or method added. You cannot directly inherit from ExtensionAbility. For details about the inheritance relationship of each ability, see [Inheritance Relationship](./js-apis-app-ability-ability.md#ability-inheritance-relationship).

> **NOTE**
> 
> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.
>
> The APIs of this module can be used only in the stage model.

## Modules to Import

```ts
import { ExtensionAbility } from '@kit.AbilityKit';
```

**Atomic service API**: This API can be used in atomic services since API version 11.

**System capability**: SystemCapability.Ability.AbilityRuntime.AbilityCore