Components in Unity are the building blocks of any game; almost everything you will use or apply will end up as a component on a GameObject inspector in a scene.
Until you build your project, Unity doesn't know which components will be in the final game when your code actually runs (there is some magic applied in the editor). So, these components are not actually attached to your GameObject inspector but rather linked to them.
In most Unity examples, you are shown how to access components through scripts by using shortcuts to the MonoBehaviour class that the game object inherits from. Accessing the components with the help of the following code:
this.renderer.collider.attachedRigidbody.angularDrag = 0.2f;
Tip
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