Hi! "Who do you think you are talking to?" means that I am more powerful or important that you think based on the way you are talking to me. It is said after someone says something disrespectful to another person, especially if the person who says it is of a higher status. For example: Employee: Boss, get me a cup of coffee and be quick about it! Boss: I'm your boss, who do you think you are talking to telling me that? I hope that answer helps!

It means someone believes not to be receiving the expected respect or treatment. In my personal opinion there aren’t many positive outcomes that come from saying that. It is a defensive stance that usually ends in conflict. If you find your self in a situation that you feel disrespected, there are better ways to de-escalate the situation:)

Who do you think that you are talking to simply means who do you think you are talking to. Its normally said by a person who is older than you or is your boss or teacher. If you are young, you speak differently when you are with your friends and when you speak to your parents or boss. Respect is normally not negotiable when speaking to your parents or boss or somebody in authority. There's a saying in English with age comes experience, and experience is not negotiable.

Just touching on previous reply there is no substitute for experience.