# UIToolkitInputBackendOption

> Input backend options for UI Toolkit events at runtime.

## Definition

* **Type:** Enum
* **Namespace:** [UnityEngine.UIElements](/engine/6000.3/script-reference/unityengine/uielements.md)
* **Assembly:** UnityEngine.UIElementsModule

> **Warning:**
>
> **Deprecated.** This enum only has one supported value. The Default backend should always be used, as it is more stable and covers all use cases.

```csharp
public enum UIToolkitInputBackendOption
```

## Fields

| Value                                                                                                                                              | Description                                                                                                                                                                                                                                                                                                                                      |
| -------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| [Default](/engine/6000.3/script-reference/unityengine/uielements/uitoolkitinputbackendoption/default.md)                                           | The initial configuration on UI Toolkit start up. This is equal to [UIToolkitInputBackendOption.InputSystemCompatibleBackend](/engine/6000.3/script-reference/unityengine/uielements/uitoolkitinputbackendoption/inputsystemcompatiblebackend.md). This option will use the Input System package is available, and the old Input Manager if not. |
| [InputSystemCompatibleBackend](/engine/6000.3/script-reference/unityengine/uielements/uitoolkitinputbackendoption/inputsystemcompatiblebackend.md) | The new Input System compatible backend allows the Input System package to send its input to UI Toolkit directly, removing the need for an EventSystem in the user scene. This option will use the Input System package is available, and the old Input Manager if not.                                                                          |