How context provides to us information about application and activity

I’m very beginner of android. while I’m studying about “Context”, there are a lot of descriptions of context.

That says, “Context let us know about current state and information of application, activity”

but, What I want to know is “How Context let us know that information” Like “A Class” has information about application, and context access to A class so we get…

I did search on google but, I cannot found any information about that.

Thanks.