# Subsystem

> The Subsystem tag assigned to the read operation.

## Definition

* **Type:** Property
* **Namespace:** [Unity.IO.LowLevel.Unsafe](/engine/6000.7/script-reference/unity/io/lowlevel/unsafe.md)
* **Assembly:** UnityEngine.CoreModule

```csharp
public readonly AssetLoadingSubsystem Subsystem { get; }
```

### Remarks

You can assign a subsystem tag to a read operation using the `subsystem` parameter of the [AsyncReadManager.Read](/engine/6000.7/script-reference/unity/io/lowlevel/unsafe/asyncreadmanager/read.md) function.