I searched on Google and Wikipedia a lot, but I could't find answers for these questions.
1) What exactly registrar company do? They update an root DNS and set there IP of my DNS?
2) How come the registrar can update records in the root DNS? How did they get this privilege? How could I get this privilege too?
3) What exactly do we pay the registrar for? Just for sending one request to the root DNS?
4) When I register a domain, am I the real (in the eye of the law) owner of the domain? How do companies (e.g. Google) protect their domain? Couldn't their registrar just say: "sorry we sold the domain to someone else"?
I hope it's not kind of an offtopic question.
Thanks in advance