# UIToolkitInputBackendOption

> Input backend options for UI Toolkit events at runtime.

## Definition

* **Type:** Enum
* **Namespace:** [UnityEngine.UIElements](/engine/6000.7/script-reference/unityengine/uielements.md)
* **Assembly:** UnityEngine.UIElementsModule

> **Warning:**
>
> **Removed.** This enum only has one supported value. The Default backend should always be used.

```csharp
public enum UIToolkitInputBackendOption
```

## Fields

| Value                                                                                                                                              | Description                                                                                                                                                                                                                                                                                                                                      |
| -------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| [Default](/engine/6000.7/script-reference/unityengine/uielements/uitoolkitinputbackendoption/default.md)                                           | The initial configuration on UI Toolkit start up. This is equal to [UIToolkitInputBackendOption.InputSystemCompatibleBackend](/engine/6000.7/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/6000.7/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 `UnityEngine.EventSystems.EventSystem` in the user scene. This option will use the Input System package is available, and the old Input Manager if not.                                               |