# OnCreate()

> Called when this system is created.

## Definition

* **Type:** Method
* **Namespace:** [Unity.Entities](/engine/7000.0/script-reference/unity/entities.md)
* **Assembly:** UnityEngine.EntitiesModule

```csharp
protected virtual void OnCreate()
```

### Remarks

Implement an OnCreate() function to set up system resources when it is created.

OnCreate is invoked before the the first time [ComponentSystemBase.OnStartRunning()](/engine/7000.0/script-reference/unity/entities/componentsystembase/onstartrunning.md) and OnUpdate are invoked.