# collisionDetectionMode

> The method used by the physics engine to check if two objects have collided.

## Definition

* **Type:** Property
* **Namespace:** [UnityEngine](/engine/6000.7/script-reference/unityengine.md)
* **Assembly:** UnityEngine.Physics2DModule

```csharp
public CollisionDetectionMode2D collisionDetectionMode { get; set; }
```