Hi Devashish,
If I got you right, you want to understand how system picks up the Component usage. If yes, then the explanation is below.
We have a concept of component interface and component usage. Component interface is just like a window to enter in to house or in other words it is the exposed interface which can be used by other components to access the component views.
Component usage is the place where we define that what all components (component interface) we are going to use.
Now coming back to your question, whenever we navigate to views of other components, system knows the component usage name in which we defined earlier that we are going to use this particular view.
While opening the view we can have different configurations based on the component usage.
Let’s say, it’s like if component usage is "A" display “field1” and “field 2” or else if component usage is "B" display “field 2” and “field 3”.
I hope it will give you a clear insight to the concept. If you still have any issues, please let us know, we will try to help you.
Regards jotsaroop singh